Datasets:

princeton-nlp

/

TextbookChapters

like 4

Although there are numerous advantages to choosing tools based on many factors, safety should be the first factor to be considered. Always choose the right tool for the job- Remember that tools have specific functions. • Screwdrivers are not impact resistant and should never be used as a chisel or pry bar. • Accessories used in cordless impact drivers must be rated for impact use. Determine the scope of work- Consider where you will be working: • Small or large project? • What tasks will you be performing? • How much space do you have to safely perform your tasks? • What are the tools best suited to the tasks? • What PPE is required for each task? Material type and size- Choice of tools and accessories should be based on the type and size of material being used. Examples: • Specially designed masonry drill bits, saw blades, and grinding wheels are used for masonry, concrete, brick and tile. • Anchor bolts are rated by the amount of weight they will safely support, with many styles available for application with specific materials. • A circular saw may be better suited for the task than a table or miter saw for small jobs. • Do the material and tools to be used require an additional person to assist in the safe completion of the task due to the weight or physical size of the material? Finally remember tools are not safe if they are not maintained and used as directed by the manufacturers.  Always do the following: • Keep all tools in good condition with regular maintenance. • Examine each tool for damage before use and do not use damaged tools. • Operate tools in accordance with manufacturers' instructions. • Use properly the appropriate personal protective equipment. 1.02: Measuring Marking Leveling an Measuring, Marking, Leveling & Layout Tools Measuring and marking tools are common to multiple trades and ensure accuracy and quality craftsmanship in the building and construction process. Measuring devices are available in fractional and metric, with classic western construction practices adopting the fractional inch configuration. While some measuring tools have the actual fractions printed (1/2″, 1/4″, and 1/8″) next to each corresponding mark on the scale, many do not and the ability to read the scale without the printed fractions may take time to develop. This is one of many reasons for the adage: “Measure twice, cut once”, which is a good habit to develop and will help to avoid costly mistakes such as over cutting and wasting material or under cutting, resulting in having to remeasure and cut the material again. While many of the following tools may be considered “carpentry” tools, the majority are regularly used in most all trades. Apparent common items to all trades include measuring devices like tape measures, rulers, and basic estimation tools; plumbers and electricians will use spirit levels, builders levels, and angle finders to ensure that piping is at an appropriate grade or conduit, fixtures, and other items are installed to meet industry codes. Levels are used to check for level (horizontal) and plumb (vertical). Trades persons will often use a combination of various levels and squares to complete a project. An interactive or media element has been excluded from this version of the text. You can view it online here: Measuring marking and leveling tools Squares are used for layout work to mark square (90°/right angle) and other angles commonly used in building and construction trades indicated on specific types of squares. They are also used to check for squareness and other angles during assembly. Squares can be made of inexpensive molded plastic, lightweight aluminum or durable steel. An interactive or media element has been excluded from this version of the text. You can view it online here: Measuring marking and leveling tools

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/07%3A_Industrial_Safety_and_Manufacturing/7.D%3A_Manufacturing_and_Maintenance-Tool_and_Equipment_Safety/1.01%3A_Tool_Choices_and_Applications.txt

Nails Nails of all sizes are commonly used to assemble wood products when glue and adhesives are not of sufficient strength for a project. They are known by number size, the lesser the number, the smaller the length and diameter. The number is followed by the letter “d”. The d is the symbol for penny, which can be traced back as far as the Ancient Roman Empire. There are various theories as to how the measurement term came to be, but what is confirmed is that the d stands for the Roman coin denarius, or in English, the penny. The denarius was the coin which many people used in the Roman empire at the time when Rome occupied what is now England, so that’s why it’s called a penny but uses a “d” as the symbol. Some styles of nails have larger heads for greater holding power while others have smaller or no head so that it can be set flush with or lower than material surfaces for cosmetic applications. When “headless” finish or casing nails are used, it is best to drive them to just slightly above the surface while being careful not to leave hammer marks on the material’s being nailed surface and then use a “nail set” tool to embed the nail. Interactive table nail specs Common Nails for Building & Construction Projects An interactive or media element has been excluded from this version of the text. You can view it online here: Interactive media nail type Hammers Hammers are used to strike or cause impact and are available in traditional designs and in a variety of models, sizes, and weights to perform specific tasks. Selecting the proper hammer for a particular task can be the determining factor for being able to complete the task or be the difference between quality and sub-par craftsmanship. The following list describes the most common types of hammers and some of the types of tasks they are often used for. An interactive or media element has been excluded from this version of the text. You can view it online here: Interactive hammer designs General Hammer Use No matter which type of hammer is used, employing proper techniques will help prevent injury. • Wear safety glasses when striking any object with any type of hammer or tool. • For hardwood, before nailing with hammer, drill pilot hole in material to prevent splitting. • Choose a hammer weight that is comfortable. • “Set” the nail by tapping in the point, remove the free hand before driving the nail. • Using the center of the hammer face, drive the nail with smooth, firm blows. • Striking face should always be parallel with the surface being hit. • Avoid sideways or glancing blows. • Always strike with the hammer face. • Avoid impact with handle or shaft of hammer. Nail Gun Safety The following information is compiled from OSHA safety literature. Please go to https://www.osha.gov/Publications/Na..._optimized.pdf if you wish to view the brochure in it’s entirety. This guidance document is not a standard or regulation, and it creates no new legal obligations. It contains recommendations as well as descriptions of mandatory safety and health standards [and other regulatory requirements]. The recommendations are advisory in nature, informational in content, and are intended to assist employers in providing a safe and healthful workplace. The Occupational Safety and Health Act requires employers to comply with safety and health standards and regulations promulgated by OSHA or by a state with an OSHA-approved state plan. In addition, the Act’s General Duty Clause, Section 5(a)(1), requires employers to provide their employees with a workplace free from recognized hazards likely to cause death or serious physical harm. Nail guns are used every day on many construction jobs—especially in residential construction. They boost productivity but also cause tens of thousands of painful injuries each year. Nail gun injuries are common—one study found that 2 out of 5 residential carpenter apprentices experienced a nail gun injury over a four-year period. When they do occur, these injuries are often not reported or given any medical treatment. Research has identified the risk factors that make nail gun injuries more likely to occur. The type of trigger system and the extent of training are important factors. The risk of a nail gun injury is twice as high when using a multi-shot contact trigger as when using a single-shot sequential trigger nailer. The guidance is for residential home builders and construction contractors, subcontractors, and supervisors. NIOSH and OSHA developed this publication to give construction employers the information they need to prevent nail gun injuries. Types of triggers and key terms are described. The guidance highlights what is known about nail gun injuries, including the parts of the body most often injured and the types of severe injuries that have been reported. Common causes of nail gun injuries are discussed and six practical steps that contractors can take to prevent these injuries are described. These are: 1. Use full sequential trigger nail guns; 2. Provide training; 3. Establish nail gun work procedures; 4. Provide personal protective equipment (PPE); 5. Encourage reporting and discussion of injuries and close calls; and 6. Provide fist aid and medical treatment. 7. The guidance includes actual workplace cases along with a short section on other types of nail gun hazards and sources of additional information. Introduction to Nail Gun Safety How likely are nail gun injuries? Nail guns are powerful, easy to operate, and boost productivity for nailing tasks. They are also responsible for an estimated 37,000 emergency room visits each year. Severe nail gun injuries have led to construction worker deaths. Nail gun injuries are common in residential construction. About two-thirds of these injuries occur in framing and sheathing work. Injuries also often occur in roofing and exterior siding and finishing A study of apprentice carpenters found that: • 2 out of 5 were injured using a nail gun during their 4 years of training. • 1 out of 5 were injured twice. • 1 out of 10 were injured three or more times. Worksite Story – A 26-year-old Idaho construction worker died following a nail gun accident in April 2007. He was framing a house when he slipped and fell. His finger was on the contact trigger of the nail gun he was using. The nosepiece hit his head as he fell, driving a 3-inch nail into his skull. The nail injured his brain stem, causing his death. The safety controls on the nail gun were found to be intact. Death and serious injury can occur using nail guns—even when they are working properly. More than half of reported nail gun injuries are to the hand and fingers. One quarter of these hand injuries involve structural damage to tendons, joints, nerves, and bones. After hands, the next most often injured are the leg, knee, thigh, foot, and toes. Less common are injuries to the forearm or wrist, head and neck, and trunk. Serious nail gun injuries to the spinal cord, head, neck, eye, internal organs, and bones have been reported. Injuries have resulted in paralysis, blindness, brain damage, bone fractures, and death. Nail guns present a number of hazards and risks. NIOSH and OSHA prepared this publication to provide builders and contractors with the latest information on nail gun hazards and practical advice on the steps they should take to prevent nail gun injuries on their construction jobs. This guide covers nail guns (also called nailers) used for fastening wood, shingles, and siding materials. The guide refers specifically to pneumatic tools but also applies to nail guns that use gas, electric, or hybrid power sources. It does NOT cover powder actuated tools used for fastening material to metal or concrete. The guide assumes that contractors are generally familiar with how nail guns work and the various types of specialized nail guns (for example, framing, roofing, flooring) This guide is applicable to all nail guns. The emphasis is on framing (“stick” and “coil”) nail guns because they fie the largest nails, are the most powerful, and are considered to be the most dangerous to use. Know Your Triggers Nail gun safety starts with understanding the various trigger mechanisms. Here is what you need to know: How Triggers Differ All nailers rely on two basic controls: a finger trigger and a contact safety tip located on the nose of the gun. Trigger mechanisms can vary based on: 1) the order in which the controls are activated, and 2) whether the trigger can be held in the squeezed position to discharge multiple nails OR if it must be released and then squeezed again for each individual nail. Combining these variations gives four kinds of triggers. Some nail guns have a selective trigger switch which allows the user to choose among two or more trigger systems. Each trigger type is described below along with a summary of how the controls are activated. An interactive or media element has been excluded from this version of the text. You can view it online here: The bottom line: contractors should check the tool label and manual for manufacturer-specific trigger names and operating information. Worksite Story – Two framers were working together to lay down and nail a subfloor. One framer was waiting and holding the nail gun with his finger on the contact trigger. The other framer was walking backwards toward him and dragging a sheet of plywood. The framer handling the plywood backed into the tip of the nail gun and was shot in the back. The nail nicked his kidney, but fortunately he recovered. As a result of this incident, the contractor switched to using only sequential triggers on framing nail guns. Co-workers can get injured if they bump into your contact trigger nail gun. You can prevent this by using a full sequential trigger. How do Nail Gun Injuries Happen? Useful Terms • Recoil is the rapid rebound or kickback after the nailer is fired. • A double fire occurs when a second nail unintentionally fires because the nailer re-contacted the work piece after recoil. It can also occur if the safety contact slips while the user is positioning the nail gun. Several tool manufacturers offer “anti-double fire” features for their nail guns. There are seven major risk factors that can lead to a nail gun injury. Understanding them will help you to prevent injuries on your jobsites. 1. Unintended nail discharge from double fire. Occurs with CONTACT triggers. The Consumer Product Safety Commission (CPSC) found that contact trigger nailers are susceptible to double firing, especially when trying to accurately place the nailer against the work piece. They found that a second unintended firing can happen faster than the user is able to react and release the trigger. Unintended nails can cause injuries. Double fire can be a particular problem for new workers who may push hard on the tool to compensate for recoil. It can also occur when the user is working in an awkward position, such as in tight spaces where the gun doesn’t have enough space to recoil. The recoil of the gun itself can even cause a non-nail injury in tight spaces if the nail gun hits the user’s head or face. 2. Unintended nail discharge from knocking the safety contact with the trigger squeezed. Occurs with CONTACT and SINGLE ACTUATION triggers. Nail guns with contact and single actuation triggers will fire if the trigger is being held squeezed and the safety contact tip gets knocked or pushed into an object or person by mistake. For example, a framer might knock his leg going down a ladder or bump into a co-worker passing through a doorway. Contact trigger nailers can release multiple nails and single actuation trigger nailers can release a single nail to cause injury. Holding or carrying contact trigger or single actuation trigger nail guns with the trigger squeezed increases the risk of unintended nail discharge. Construction workers tend to keep a finger on the trigger because it is more natural to hold and carry an 8-pound nail gun using a full, four-finger grip. Tool manufacturers, however, do warn against it. 3. Nail penetration through lumber work piece. Occurs with ALL trigger types. Nails can pass through a work piece and either hit the worker’s hand or fly of as a projectile (airborne) nail. A blow-out nail is one example. Blow-outs can occur when a nail is placed near a knot in the wood. Knots involve a change in wood grain, which creates both weak spots and hard spots that can make the nail change direction and exit the work piece. Nail penetration is especially a concern for placement work where a piece of lumber needs to be held in place by hand. If the nail misses or breaks through the lumber it can injure the non-dominant hand holding it. 4. Nail ricochet after striking a hard surface or metal feature. Occurs with ALL trigger types. When a nail hits a hard surface, it has to change direction and it can bounce of the surface, becoming a projectile. Wood knots and metal framing hardware are common causes of ricochets. Problems have also been noted with ricochets when nailing into dense laminated beams. Ricochet nails can strike the worker or a co-worker to cause an injury. 5. Missing the work piece. Occurs with ALL trigger types. Injuries may occur when the tip of the nail gun does not make full contact with the work piece and the discharged nail becomes airborne. This can occur when nailing near the edge of a work piece, such as a plate. Positioning the safety contact is more difficult in these situations and sometimes the fired nail completely misses the lumber. Injuries have also occurred when a nail shot through plywood or oriented strand board sheeting missed a stud and became airborne. 6. Awkward position nailing. Occurs with ALL trigger types. Unintended discharges are a concern in awkward position work with CONTACT and SINGLE ACTUATION triggers. Nailing in awkward positions where the tool and its recoil are more difficult to control may increase the risk of injury. These include toe-nailing, nailing above shoulder height, nailing in tight quarters, holding the nail gun with the non-dominant hand, nailing while on a ladder, or nailing when the user’s body is in the line of fie (nailing towards yourself). Toe-nailing is awkward because the gun cannot be held flush against the work piece. Nailing from a ladder makes it difficult to position the nail gun accurately. Nailing beyond a comfortable reach distance from a ladder, elevated work platform, or leading edge also places the user at risk for a fall. 7. Bypassing safety mechanisms. Occurs with ALL trigger types. Bypassing or disabling certain features of either the trigger or safety contact tip is an important risk of injury. For example, removing the spring from the safety contact tip makes an unintended discharge even more likely. Modifying tools can lead to safety problems for anyone who uses the nail gun. Nail gun manufacturers strongly recommend against bypassing safety features, and voluntary standards prohibit modifications or tampering. OSHA’s Construction standard at 29 CFR 1926.300(a) requires that all hand and power tools and similar equipment, whether furnished by the employer or the employee shall be maintained in a safe condition. About 1 in 10 nail gun injuries happen to co-workers. This is from either airborne (projectile) nails or bumping into a co-worker while carrying a contact trigger nail gun with the trigger squeezed. You Should Know – Studies of residential carpenters found that the overall risk of nail gun injury is twice as high when using contact trigger nail guns compared to using sequential trigger nail guns. *Note that the studies could not quantify injury risks associated with specific tasks; it is likely that some nailing tasks are more dangerous than others. A voluntary ANSI standard 10 calls for all large pneumatic framing nailers manufactured after 2003 to be shipped with a sequential trigger. However, these may not always be FULL SEQUENTIAL triggers. Contractors may need to contact manufacturers or suppliers to purchase a FULL SEQUENTIAL trigger kit. Worksite Story – A carpenter apprentice on his fist day ever using a nail gun injured his right leg. He was working on a step ladder and was in the process of lowering the nail gun to his side when the gun struck his leg and fired a nail into it. He had no training prior to using the nail gun. New worker training is important and should include hands-on skills. Six Steps to Nail Gun Safety 1. Use the full sequential trigger The full sequential trigger is always the safest trigger mechanism for the job. It reduces the risk of unintentional nail discharge and double fires—including injuries from bumping into co-workers. • At a minimum, provide full sequential trigger nailers for placement work where the lumber needs to be held in place by hand. Examples include building walls and nailing blocking, fastening studs to plates and blocks to studs, and installing trusses. • Unintended nail discharge is more likely to lead to a hand or arm injury for placement work compared to flat work, where the lumber does not need to be held in place by hand. Examples of flat work include roofing, sheathing, and subflooring. • Consider restricting inexperienced employees to full sequential trigger nail guns starting out. Some contractors using more than one type of trigger on their jobs color-code the nail guns so that the type of trigger can be readily identified by workers and supervisors. • Some contractors have been reluctant to use full sequential triggers fearing a loss of productivity. How do the different types of triggers compare? • The one available study had 10 experienced framers stick-build two identical small (8 f x 10 ft. wood structures—one using a sequential trigger nail gun and one using a contact trigger nail gun. Small structures were built in this study so that there would be time for each carpenter to complete two sheds. • Average nailing time using the contact trigger was 10% faster, which accounted for less than 1% of the total building time when cutting and layout was included. However, in this study the trigger type was less important to overall productivity than who was using the tool; this suggests productivity concerns should focus on the skill of the carpenter rather than on the trigger. • Although the study did not evaluate framing a residence or light commercial building, it shows that productivity is not just about the trigger. The wood structures built for the study did include common types of nailing tasks (flat nailing, through nailing, toe-nailing) and allowed comparisons for both total average nailing time and overall project time. The study did not compare productivity differences for each type of nailing task used to build the sheds. 2. Provide training Both new and experienced workers can benefit from safety training to learn about the causes of nail gun injuries and specific steps to reduce them. Be sure that training is provided in a manner that employees can understand. Here is a list of topics for training: • How nail guns work and how triggers differ. • Main causes of injuries – especially differences among types of triggers. • Instructions provided in manufacturer tool manuals and where the manual is kept. Hands-on training with the actual nailers to be used on the job. This gives each employee an opportunity to handle the nailer and to get feedback on topics such as: • How to load the nail gun • How to operate the air compressor • How to fie the nail gun • How to hold lumber during placement work • How to recognize and approach ricochet-prone work surfaces • How to handle awkward position work (e.g., toe-nailing and work on ladders) • How best to handle special risks associated with contact and single actuation triggers such as nail gun recoil and double fires. For example, coach new employees on how to minimize double fires by allowing the nail gun to recoil rather than continuing to push against the gun after it fires. • What to do when a nail gun malfunctions. *Training should also cover items covered in the following sections of the guidance, such as company nail gun work procedures, personal protective equipment, injury reporting, and fist aid and medical treatment. You Should Know • Training is important: Untrained workers are more likely to experience a nail gun injury than a trained worker. • Training does not trump triggers: Trained workers using contact triggers still have twice the overall risk of injury as trained workers using sequential triggers. 3. Establish nail gun work procedures Contractors should develop their own nail gun work rules and procedures to address risk factors and make the work as safe as possible. Examples of topics for contractor work procedures include but are not limited to the following Do’s & Don’ts: DO’s • Make sure that tool manuals for the nailers used on the job are always available on the jobsite. • Make sure that manufacturers’ tool labels and instructions are understood and followed. • Check tools and power sources before operating to make sure that they are in proper working order. • Take broken or malfunctioning nail guns out of service immediately. • Set up operations so that workers are not in the line of fire from nail guns being operated by co-workers. • Check lumber surfaces before nailing. Look for knots, nails, straps, hangers, etc. that could cause recoil or ricochet. • Use a hammer or positive placement nailer when nailing metal joinery or irregular lumber. • For placement work, keep hands at least 12 inches away from the nailing point at all times. Consider using clamps to brace instead of your hands. • Always shoot nail guns away from your body and away from co-workers. • Always disconnect the compressed air when: • Leaving a nailer unattended • Travelling up and down a ladder or stairs • Passing the nail gun to a co-worker • Clearing jammed nails • Performing any other maintenance on the nail gun • Recognize the dangers of awkward position work and provide extra time and precautions: • Use a hammer if you cannot reach the work while holding the nailer with your dominant hand. • Use a hammer or reposition for work at face or head height. Recoil is more difficult to control and could be dangerous. • Use a hammer or full sequential trigger nailer when working in a tight space. Recoil is more difficult to control and double fires could occur with contact triggers. • Take extra care with toe-nailing. • Nail guns can slip before or during firing because the gun cannot be held flush against the work piece. • Use a nail gun with teeth on the safety contact to bite into the work piece to keep the gun from slipping during the shot. • Use the trigger to fire only after the safety contact piece is positioned. • Recognize the dangers of nail gun work at height and provide extra time and precautions: • Set up jobs to minimize the need for nailing at height • Consider using scaffolds instead of ladders • If work must be done on ladders, use full sequential trigger nailers to prevent nail gun injuries which could occur from bumping a leg while climbing up or down a ladder. • Position ladders so you don’t have to reach too far. Your belt buckle should stay between the side rails when reaching to the side. • Maintain three points of contact with the ladder at all times to prevent a fall—this means that clamps may need to be used for placement work. Holding a nailer in one hand and the work piece with the other provides only two points of contact (your feet). Reaching and recoil can make you lose your balance and fall. Falls, especially with contact trigger nailers, can result in nail gun injuries. Don’ts • Never bypass or disable nail gun safety features. This is strictly prohibited. • Tampering includes removing the spring from the safety-contact tip and/or tying down, taping or otherwise securing the trigger so it does not need to be pressed. Tampering increases the chance that the nail gun will fie unintentionally both for the current user and anyone else who may use the nail gun. Nail gun manufacturers strongly recommend against tampering and OSHA requires that tools be maintained in a safe condition. • There is NO legitimate reason to modify or disable a nail gun safety device. • Encourage workers to keep their fingers off the trigger when holding or carrying a nail gun. If this is not natural, workers should use a full sequential nail gun or set down the nailer until they begin to nail again. • Never lower the nail gun from above or drag the tool by the hose. • If the nail-gun hose gets caught on something, don’t pull on the hose. Go find the problem and release the hose. • Never use the nailer with the non-dominant hand. 4. Provide Personal Protective Equipment (PPE) Safety shoes, which help protect workers’ toes from nail gun injuries, are typically required by OSHA on residential construction sites. In addition, employers should provide, at no cost to employees, the following protective equipment for workers using nail guns: • Hard hats • High Impact eye protection – safety glasses or goggles marked ANSI Z87.1 • Hearing protection – either earplugs or earmuff 5. Encourage reporting and discussion of injuries and close calls Studies show that many nail gun injuries go unreported. Employers should ensure that their policies and practices encourage reporting of nail gun injuries. Reporting helps ensure that employees get medical attention. It also helps contractors to identify unrecognized job site risks that could lead to additional injuries if not addressed. Injuries and close calls provide teachable moments that can help improve crew safety. If you have a safety incentive program, be sure that it does not discourage workers from reporting injuries. Employers that intentionally under report work-related injuries will be in violation of OSHA’s injury and illness recordkeeping regulation. 6. Provide fist aid and medical treatment Employers and workers should seek medical attention immediately after nail gun injuries, even for hand injuries that appear to be minimal. Studies suggest that 1 out of 4 nail gun hand injuries can involve some type of structural damage such as bone fracture. Materials such as nail strip glue or plastic or even clothing can get embedded in the injury and lead to infection. Barbs on the nail can cause secondary injury if the nail is removed incorrectly. These complications can be avoided by having workers seek immediate medical care. Worksite Story – A construction worker accidentally drove a 16 penny framing nail into his thigh. It didn’t bleed much and he didn’t seek medical care. He removed the nail himself. Three days later he felt a snap in his leg and severe pain. In the emergency room, doctors removed a sheared piece of nail and found that his thigh bone had fractured. Not all injuries are immediately visible. Failure to seek medical care can result in complications and more serious injuries. Other Hazards Air Pressure Pneumatic tools and compressor use are regulated under OSHA’s Construction standard at 29 CFR 1926.302(b). The provisions in this standard that are relevant for nail guns are provided below: 1. Pneumatic power tools shall be secured to the hose or whip by some positive means to prevent the tool from becoming accidentally disconnected. 2. All pneumatically driven nailers, staplers, and other similar equipment provided with automatic fastener feed, which operate at more than 100 p.s.i. pressure at the tool shall have a safety device on the muzzle to prevent the tool from ejecting fasteners, unless the muzzle is in contact with the work surface. 3. The manufacturer’s safe operating pressure for hoses, pipes, valves, filters, and other fitting’s shall not be exceeded. 4. The use of hoses for hoisting or lowering tools shall not be permitted. Noise Pneumatic nail guns produce short (less than a tenth of a second in duration) but loud “impulse” noise peaks: one from driving the nail and one from exhausting the air. Most nail gun manufacturers recommend that users wear hearing protection when operating a nailer. Available information indicates that nail gun noise can vary depending on the gun, the work piece, air pressure, and the work setting. The type of trigger system does not appear to affect the noise level. Peak noise emission levels for several nailers ranged from 109 to 136 dBA.15,16 These loud short bursts can contribute to hearing loss. Employers should provide hearing protection in the form of earplugs or muff and ensure that they are worn correctly. Employers should also ask about noise levels when buying nail guns—studies have identified ways to reduce nail gun noise and some manufacturers may incorporate noise reduction features. Musculoskeletal disorders Framing nail guns can weigh up to 8 pounds and many framing jobs require workers to hold and use these guns for long periods of time in awkward hand/arm postures. Holding an 8-pound weight for long periods of time can lead to musculoskeletal symptoms such as soreness or tenderness in the fingers, wrist, or forearm tendons or muscles. These symptoms can progress to pain, or in the most severe cases, inability to work. No studies have shown that one trigger type is any more or less likely to cause musculoskeletal problems from long periods of nail gun use. If use of a nail gun is causing musculoskeletal pain or symptoms of musculoskeletal disorders, medical care should be sought. Conclusion Nail gun injuries are painful. Some cause severe injuries or death. Nail gun injuries have been on the rise along with the increased popularity of these powerful tools. These injuries can be prevented, and more and more contractors are making changes to improve nail gun safety. Take a look at your practices and use this guide to improve safety on your job sites. Working together with tool gun manufacturers, safety and health professionals, and other organizations, we can reduce nail gun injuries.

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/07%3A_Industrial_Safety_and_Manufacturing/7.D%3A_Manufacturing_and_Maintenance-Tool_and_Equipment_Safety/1.03%3A_Nails_Hammers_and_Pneumatic_N.txt

Threaded Fasteners Selecting the appropriate fastener for a particular application involves considering many factors to include: functionality, strength and durability, exposure to natural elements, and aesthetics.While most bolts and many screws are designed for the head to press firmly against flat surfaces of materials and parts, screws with tapered or bugle style heads are manufactured to be countersunk even with or below material surfaces. Screws, bolts and other threaded fastener accessories are normally made of brass; or mild, hardened or stainless steel; or plastics in some designed for lighter and cosmetic applications. In many cases, threaded fasteners are treated with processes such as galvanization, electroplated phosphate, or chemical primers such as zinc oxide. Screws are taper tipped and threaded in a manner that helps wood, or other materials, draw together as the screw is inserted. They are used in place of nails when stronger joining power is needed. A screw makes its own thread pattern in the material. Screw head shapes (slotted, pan, hex, oval, flat) vary according to the application. Also the slots or drive types of screws are available in a wide variety (slotted, Phillips, Robertson, square, Pozidrive®, etc.). An interactive or media element has been excluded from this version of the text. You can view it online here: Interactive media common screw types Bolts are male threaded fasteners that require a female threaded counterpart (a “nut” or a threaded hole in a material) in order to secure themselves. Nuts and bolts allow for future disassembly and when used with flat and locking style washers, provide strong mechanical bonds and stability. These threaded fasteners are available in coarse and fine thread configurations which are recognized by the amount of threads per inch (tpi) in SAE fasteners and by pitch in metric fasteners. Cap head and stove type bolts are also rated by their hardness or shear strength. Various cast or embossed markings can be found on the head of these kinds of bolts, with each type of marking symbolizing a bolt’s capacity. Specialty Anchors Specialty anchors such as eye hooks, J-hooks for drywall, masonry, tile, wood, and other materials are available in both screw and bolt designs. Tap and Die sets can be used to thread materials to accept another fastener. Taps are tools made to cut female threads while Dies are tools designed to cut male threads on round stock materials. It is important that the drilled hole size for tapping, or the diameter of the material to be threaded with a die, be of a specific size and tolerance so that the final threaded product fits properly. Taps and dies are also individually available in each machine fastener diameter and thread count. An interactive or media element has been excluded from this version of the text. You can view it online here: Interactive media common bolts All of the fasteners listed above require tool to tighten when assembling projects and loosen them when disassembly is required. Drivers, pliers and wrenches facilitate the assembly of items with threaded objects such as nuts, bolts, screws, plumbing and electrical fittings and pipes. Various styles of pliers can also be used to cut, bend, pull and crimp materials and mechanical fittings. While the proper selection of tools for particular fastener or fitting will result in easier and more rapid assembly and disassembly of projects, improper tool selection may result in material, parts, and tool damage, lost time, and possible injury. Drivers An interactive or media element has been excluded from this version of the text. You can view it online here: Interactive media drivers Pliers Pliers are primarily used to grip objects that utilize leverage. Different configurations of the jaw are also used to grip, turn, pull, crimp and sometimes cut a variety of things. Many types are commonly identified by a manufacturer brand or model name and used by workers in multiple construction trades fields (Channellock® is a registered trademark for a manufacturer that makes numerous styles of tools, however tongue and groove pliers are commonly referred to as channel-lock pliers). An interactive or media element has been excluded from this version of the text. You can view it online here: Interactive media pliers Wrenches Wrenches can be used to turn bolts, nuts, or other hard to turn items. Wrenches provide excellent leverage compared to pliers, and most are designed to fit specific sized fasteners. The choice of an appropriate wrench depends upon the torque or leverage required to perform a function or the design of a fastener. The wrong choice of a wrench for a task can cause slipping of the wrench, damage materials and parts, and result in bodily injury. As nuts, bolts, and fasteners are offered in standardized fractional (SAE (Society of Automotive Engineers) and metric (millimeter or mm.) sizes, most wrenches are designed to fit hexagonal (six-sided) or hex fasteners and mechanical fittings. Wrenches can be purchased either individually or in sets based on style or combinations of styles. An interactive or media element has been excluded from this version of the text. You can view it online here: Interactive media wrenches Tool Tips: • Only use bits and sockets rated for impact use with impact drivers and impact wrenches. Non-impact tools are made of materials that can crack, break, or shatter when used with impact tools. • Apply a penetrating oil according to manufacturer directions to rusted fasteners prior to trying to loosen them. • “Stuck” or rusted nuts, bolts, and screws can sometimes be freed by striking them sharply on the head with a steel punch. • Traditional fasteners turn in a clockwise direction to tighten and counter-clockwise to loosen. Fasteners of this design are also known as “right-hand” threaded fasteners. • Specialty fasteners required for certain mechanical applications turn counter-clockwise to tighten and clockwise to loosen. These are also referred to as “left-hand” threaded fasteners.

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/07%3A_Industrial_Safety_and_Manufacturing/7.D%3A_Manufacturing_and_Maintenance-Tool_and_Equipment_Safety/1.04%3A_Threaded_Fasteners_Drivers_Pl.txt

Choices Saws should be chosen based on the material type to be cut and the particular task being performed. Each type of saw has it’s own purpose, may be available in a variety of sizes, and offer safety and convenience features which vary by manufacturer, style, and application. For example: Circular saws are used to cut a wide variety of construction materials with an appropriate blade. They are manufactured in a variety of sizes that can be selected according to the project. Simple projects with 1″ x 4″ or 1/2″ plywood material may only require a 5-3/8″ cordless trim saw, whereas beam construction could require a circular beam saw with a 21″ course toothed blade, and cement fiber plank siding installation using a 7-1/4″ circular saw with the appropriate blade. While most stationary saw models are primarily used in the carpentry trades, most portable models are also employed in plumbing, electrical, and other construction and facility maintenance trades. As in the case of numerous hand tools and accessories, many of the saws types have become known by industry workers as common trademark, brand, or model names: • Circular Saw- Skilsaw™ (Skilsaw Inc.) • Reciprocating Saw- Sawzall® (Milwaukee Electric Tool Company); TigerSaw® (Porter Cable Tool Company) Saw Blades Blades come in various sizes and configurations. When choosing a saw for a particular cut, it is important to consider the type of material to be cut and the finish desired. Saw blades are rated in teeth per inch (t.p.i.), The lesser t.p.i., or the lower the revolutions per minute (r.p.m.), the rougher the finish of the cut will be. Always check the r.p.m. rating of both the blade and the saw to ensure they are compatible. Choosing a toothed blade or abrasive cut-off blade that is not rated for the r.p.m. rating of the saw can result in catastrophic blade failure and injury. The thickness of the saw blade is referred to as the Kerf. This measurement is the width of the path of the cut where material will be removed. For accurate final dimensions, the kerf of the blade should always travel on the waste side of a marked line. Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Interactive media saw blades Additional Basic Saw Terminology • Rip Cut- cut follows or goes with the grain of the material. • Cross cut- cut goes across the grain of the material. • Push-block/Push Stick- A hand-held device designed to push the work piece into and past cutting edges on stationary power tools. • Scroll action- blade strokes perpendicular to material surface. Common to saber saws, scroll saws, and reciprocating saws. • Orbital action- blade follows arcing path. Available option for saber and reciprocating saws. Aids in cutting pipe and round or circular materials. Saw Safety • Never disable manufacturer installed guards or safety devices. • Always use safety glasses. • Do not use a saw for any purpose it’s features are not intended for. • Always refer to manufacturer’s operating instructions and safety procedures prior to operating any power tool. *Kickback is caused when the material binds with the blade or fence of a saw resulting in the material being forcefully ejected, often drawing the operator’s hand/s toward the moving blade, creating the potential for serious injury or death. Although kickback is regularly associated with table saw use, the same potential hazard exists with circular, reciprocating, saber and any other type of saw. In addition to material being ejected and the operator being drawn toward the blade, kickback can also result in portable saws being ejected from the material toward the operator. Saw Types and Applications Circular Saw- portable (framing and trim) Circular saws are used to cut a wide variety of construction materials with an appropriate blade. They are constructed in various sizes that can be selected according to the project. Simple projects with 1″ x 4″ or 1/2″ plywood material may only require a 5-3/8″ cordless trim saw, whereas beam construction could require a beam saw with a 21″ course toothed blade. An interactive or media element has been excluded from this version of the text. You can view it online here: Circular Saw Safety Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Miter Saw- cuts angles, compound angles & bevels The interactive or media element is excluded from the print version of the text. You can view it online here: Miter Saw Safety Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Query \(1\) Table Saw- for rip & cross cuts of sheet goods and lumber stock Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Table Saw Safety Query \(1\) This interactive or media element is excluded from the print version of the text. You can view it online here: Sabre Saws (Jigsaw) and Scroll Saws- curved cuts, uses U-shank and/or T-shank (bayonet) blades Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Reciprocating Saw- rough cuts and demolition *Many jigsaws & reciprocating saws can be used in either scrolling or orbital modes Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Interactive media jig saw Other Saws A variety of saws are available for masonry and mechanical applications and may be specific to a specific trade or task. Examples: Band Saws – vertical and horizontal models for wood, metal, & other material applications Tile Saws – ceramic, porcelain, quarry, clay, and glass Block Saws – concrete, brick, and glass Masonry Saws – Blades used for tile, cement, brick, & asphalt are usually diamond coated or abrasive. The can also be used wet or dry.

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/07%3A_Industrial_Safety_and_Manufacturing/7.D%3A_Manufacturing_and_Maintenance-Tool_and_Equipment_Safety/1.05%3A_Saws.txt

Drills Drills are used to bore holes, tighten and loosen fasteners, and, with some models and accessories, mix paint, mortar, and similar materials, and to chisel and chip mortar, concrete, and other dense or hard materials. The selection of the proper dill for a job requires knowledge of the material being worked, the types and models of drills and their purposes, and the accessories that are appropriate for the task. Tool makers offer all of the types of drills in corded models and the majority of them are also available in variable speed and battery powered models that offer greater portability and reduced tool weight with lighter weight DC brushless motor technology. Drill Safety 1. Wear safety glasses when operating with portable electric drill. 2. Disconnect the drill from the electrical supply when installing bits. 3. Clamp stock so it will not move during the drilling operation. 4. Before drilling, turn the drill on to see if the bit is centered and running true. 5. Align the bit with the desired hole location before turning the drill on. 6. Hold the drill firmly with both hands while drilling. 7. When drilling deep holes with a twist drill, move the bit up and down several times while drilling to remove cuttings and reduce overheating in the bit. 8. Do not allow the cord to become wrapped around the drill when working. 9. If the electrical cord becomes frayed or starts to separate from the drill housing, repair it immediately! 10. Remove the bit from the drill as soon as the work is completed. 11. Select the correct bit for the finish and material being drilled. Make sure the bit is securely tightened in the drill chuck. 12. Be extremely careful when using larger portable electric drills (3/8″ and 1/2″). If the bit should hang or get caught the drill will twist in the operator’s hands causing a sprain or bruised fingers. 13. Always remove the key from the chuck before drilling. 14. To prevent seizing, reduce the feed pressure when the drill bit is about to come through the material. Drill Operating Procedures 1. Always center punch or make a starting indentation in the material being drilled to get an accurate starting point for the drill bit. 2. Tighten the drill bit by rotating the chuck key to all three holes in the chuck. This will help to keep the drill bit centered. 3. Apply moderate even pressure to the drill during the drilling operation. If excessive pressure is required to make the bit cut then the bit is dull and needs to be sharpened. 4. Maintain good balance at all times when drilling. 5. Use slow drill speeds for drilling metal and fast speeds for drilling wood. 6. To obtain holes that are placed accurately, drill a small pilot first then drill the final hole. Drill Types Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Interactive media drills Bits & Accessories Along with using the driver bits for various fasteners discussed in the previous chapter, drills can be accessorized to perform a variety of functions. Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Interactive media drill bits

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/07%3A_Industrial_Safety_and_Manufacturing/7.D%3A_Manufacturing_and_Maintenance-Tool_and_Equipment_Safety/1.06%3A_Drills_and_Accessories.txt

Grinders Grinders are normally used to either smooth or cut hard surfaces and materials depending upon the type of accessory and material being used. The basic grinding tool consists of a motor with an abrasive wheel, wire brush or other attachment attached to the arbor (shaft) by a female threaded fastener (arbor nut). Some manufacturers’ arbor nut configuration requires a propitiatory wrench or spanner for removal and installation of their own specially designed style of fastener. Grinders are offered in both portable and stationary models, and some come with a variable speed option. Each style of grinder can be accessorized for specific applications and functions and components differ by manufacturer. Grinder Safety When choosing accessories for grinders, it is extremely important to note the the revolutions per minute (r.p.m.) rating of the accessory meets or exceeds the r.p.m. of the grinder. An inappropriately sized grinder accessory can shatter or break resulting in injury. Grinders should always be unplugged or the battery should be disconnected from the tool before changing accessories. Portable grinders, like many other rotating power tools, have the potential for kickback and operators should take the same basic precautions as when operating a portable power saw. Bench grinders have tool rests, or tables for stabilizing items being ground. These should be adjusted as close to the grinding wheel as possible to prevent injury in the event of the wheel grabbing the item and pulling the operators hand/s in the direction of the wheel. Bench grinders are also required to have adjustable, impact resistant, clear lens guards, protective eye wear should always be worn by the operator when using any grinder. Due to the wide variety of grinding tools and applications, be sure to consult manufacturer directions before operating any power tool you are unfamiliar with. Although some of these tools are also offered in special versions that can be used in the presence of water to cool the blade or stone and flush debris from the cut or material surface, most grinders are not suited for wet applications. Types of Grinders Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Interactive media sanders Grinder Accessories Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Interactive media grinder and accessories Sanding Discs for grinders usually require a hard rubber backing plate to be attached to the grinder and for the disc to be attached to the backing plate by an adhesive or hook-and-loop fastening system, to create an orbital sander. The disc’s sandpaper material composition should be selected according to the material being sanded (see Sandpaper Material Composition). Buffing Bonnets and Wheels used for buffing metals, plastics, quarry stone and other surfaces can be made of cotton, microfiber, and other materials regularly used in hand polishing items. While bonnets are mounted to backing plates on portable grinders of buffers, buffing wheels are mounted to the arbor of stationary grinders with the arbor nut. Sanders Regardless of whether you are sanding by hand or using a power sander, identifying the right sanding tool and sandpaper to be used for a project can be a daunting task if you’re unfamiliar with the capability of the sanding tools and the variety of sandpapers available for specific applications. Sanders can be used to form and shape a wide variety of materials and to strip or create fine finishes. When working with electric power sanders, when the tool is fitted with a variable speed option, the speed should be adjusted to a speed that creates the best cutting action in order to realize the full potential of the tool and sandpaper being used based on the material being sanded and the finish desired. As with other power tools, it is important to let the tool do the work. Too much pressure on the tool can slow or dampen the machine’s action, creating less cutting action due to excessive friction or not allowing the tool to rotate or vibrate at all. Some sanders rotate in one continuous motion (orbital or track) that can leave sanding lines or swirl marks in materials. Random orbital and oscillating sanders work in multiple pathways that create fewer lines and finer finishes. Types of Sanders Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here: Sand Paper Styles Grit is the term use to identify the coarseness (roughness) of the material on the sandpaper. Sandpapers are labeled by a number denoting their coarseness: the lower the number, the coarser the grit of the sandpaper and rougher finish; the higher the number, the finer the grit and smoother finish. The sandpaper’s cutting material can consist of aluminum oxide, garnet, or silicon, and can even be used in emery cloth that resist breakdown in wet applications. For sanding items that require extensive work, it is best to start with a coarse sandpaper, graduating incrementally to finer grits to obtain the desired finish. Material Composition • Garnet quarry stone is crushed to a specified grain size and used to coat paper or cloth to make sandpaper and sanding belts commonly used for universal applications. Wears out faster than other sandpapers but is capable of creating smoother finishes. • Aluminum Oxide works good for sanding wood and metal. As aluminum oxide particles flake off during use creating new sharp edges, this media lasts longer than garnet sandpaper, but does not create as smooth of a finish. • Silicon Carbide is harder than garnet or aluminum oxide. This media is commonly used for metal, plastics, and fiberglass, but is a poor choice for applications with wood. Emery Cloth is a cloth material coated with a granular mineral substance normally consisting of corundum mixed with magnetite or hematite. Emery cloth is capable of holding up in wet applications and is relied upon by plumbers to clean and etch copper pipes and fittings prior to soldering. Query \(1\) The interactive or media element is excluded from the print version of the text. You can view it online here:

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/07%3A_Industrial_Safety_and_Manufacturing/7.D%3A_Manufacturing_and_Maintenance-Tool_and_Equipment_Safety/1.07%3A_Grinders_Sanders_and_Accessor.txt

Thumbnail: Image, www.cpwr.com 08: Safety in Leadership and Planning Reflection: Firearms in the workplace - Whose Rights? Every worker is guaranteed a safe workplace. Share how you would address competing interests concerning safety in the workplace. For example how do you balance the right to carry a concealed fire-arm with someone else's right to feel safe and secure in their workspace considering the many active shooter events in the US every year. Flash Cards: Key Terms and Definitions, Standards This interactive feature not available in print version of this workbook Draft an FPP and EAP Reference the standards for Fire Prevention and Emergency Planning and craft a simple FPP and EAP for work at a construction site. The businesses may be electrical contractors, welding contractors, carpenters, plumbers, hvac, flooring, painters. Consider how a declaration of a pandemic would affect the work and workplace and where it might fall in the emergency plan or planning process. Discuss and consider all emergencies that should be addressed in the plan. Provide a one to two paragraph summary of the typical work done daily at a jobsite and then address the following: 1910.39(a) Application. An employer must have a fire prevention plan when an OSHA standard in this part requires one. The requirements in this section apply to each such fire prevention plan. 1910.39(b) Written and oral fire prevention plans. A fire prevention plan must be in writing, be kept in the workplace, and be made available to employees for review. However, an employer with 10 or fewer employees may communicate the plan orally to employees. 1910.39(c) Minimum elements of a fire prevention plan. A fire prevention plan must include: 1910.39(c)(1) A list of all major fire hazards, proper handling and storage procedures for hazardous materials, potential ignition sources and their control, and the type of fire protection equipment necessary to control each major hazard; 1910.39(c)(2) Procedures to control accumulations of flammable and combustible waste materials; 1910.39(c)(3) Procedures for regular maintenance of safeguards installed on heat-producing equipment to prevent the accidental ignition of combustible materials; 1910.39(c)(4) The name or job title of employees responsible for maintaining equipment to prevent or control sources of ignition or fires; and 1910.39(c)(5) The name or job title of employees responsible for the control of fuel source hazards. 1910.39(d) Employee information. An employer must inform employees upon initial assignment to a job of the fire hazards to which they are exposed. An employer must also review with each employee those parts of the fire prevention plan necessary for self-protection. 1910.38(a) Application. An employer must have an emergency action plan whenever an OSHA standard in this part requires one. The requirements in this section apply to each such emergency action plan. 1910.38(b) Written and oral emergency action plans. An emergency action plan must be in writing, kept in the workplace, and available to employees for review. However, an employer with 10 or fewer employees may communicate the plan orally to employees. 1910.38(c) Minimum elements of an emergency action plan. An emergency action plan must include at a minimum: 1910.38(c)(1) Procedures for reporting a fire or other emergency; 1910.38(c)(2) Procedures for emergency evacuation, including type of evacuation and exit route assignments; 1910.38(c)(3) Procedures to be followed by employees who remain to operate critical plant operations before they evacuate; 1910.38(c)(4) Procedures to account for all employees after evacuation; 1910.38(c)(5) Procedures to be followed by employees performing rescue or medical duties; and 1910.38(c)(6) The name or job title of every employee who may be contacted by employees who need more information about the plan or an explanation of their duties under the plan. 1910.38(d) Employee alarm system. An employer must have and maintain an employee alarm system. The employee alarm system must use a distinctive signal for each purpose and comply with the requirements in § 1910.165. 1910.38(e) Training. An employer must designate and train employees to assist in a safe and orderly evacuation of other employees. Case Study - Fatality Working in your discussion groups, review the case below and two of the eight recommendations. What specific standards from the Fire Prevention standard 1926 Subpart F were not followed. What section of the SDS would address the hazards. • Use wood floor finishing products that are less flammable (products with flash points greater than 100° F) for indoor applications • Develop, implement, and enforce a written hazard communication program that includes training employees about the chemicals they work with and the associated hazards and controls of these chemicals. Floor Sander Dies When Wood Floor Refinish Product Ignites Massachusetts Case Report: 05-MA-044 Release Date: March 31, 2006 Summary On July 2, 2005, a 43-year-old floor sander (the victim) was fatally injured when the one story single family house he was working in caught fire. The victim and a co-worker had just finished installing hardwood floors and were finishing them. The incident occurred when the flammable lacquer floor sealer that they were applying ignited, causing the house to catch fire. Calls were placed to Emergency Medical Services (EMS) and the fire department. Within minutes, EMS and fire department personnel arrived at the site to attend to the victim and control the fire. The victim was pronounced dead at the scene. The co-worker was able to exit the house without injuries. Investigation The company was hired to install and finish hard wood floors in the living room and hallway of a one-story single family house. The incident occurred on a Saturday, the victim and the co-worker’s first day on-site for this job. They arrived at the house at 7:30 a.m. to start the job. The owners of the house were not home at this time. The living room and the connecting hallway were the two locations where the hardwood floors were being installed. A closet, which housed a gas hot water heater and gas furnace, was located off the living room. A bathroom was located off the hallway. One of the first tasks they performed on-site was removing the wall to wall carpet in the living room and the hallway. The carpet was rolled up and removed from the house. The victim and co-worker then started installing the unfinished wood floors. At approximately 3:30 p.m. the wood floor installation was complete. The home owner had stopped by the house and was informed that the wood floors were installed and that the next task was to sand and apply a lacquer sealer and that by 6:00 p.m. the lacquer sealer would be dry enough to walk on the floors. The home owner left and the victim and the co-worker started sanding the floors. The sanding creates a smooth surface and prepares the wood floor for the application of the finishing products. The wood floor sanding was completed a little before 5:00 p.m. and the wood dust was cleaned from the area. The first product applied to the wood floors was a lacquer sealer. A five gallon container of the lacquer sealer was brought inside the house from the work van. According to the manufacturer’s material safety data sheet, the lacquer sealer being used contained, but was not limited to, acetone, toluene, xylene and keytones and had the following physical characteristics: • Hazardous Material Identification System (HMIS) ratings of: health (2), flammability (3), and instability (0). HMIS is a numerical rating system ranging from zero to four: minimal hazard (0), slight hazard (1), moderate hazard (2), serious hazard (3), and severe hazard (4) (Figure 1). • Vapor density rating greater than one (this lacquer sealer is heavier than air). • Percent volatile (the percentage of a liquid or solid that will evaporate at an ambient temperature of 70° Fahrenheit (F)) rating of 72% – 84%. • Flash point (lowest temperature at which a chemical’s vapors are concentrated enough to ignite) rating of 9° F. • Flammability classification rating of 1B (flash point below 73° F and boiling point at or above 100° F). The victim and co-worker started to apply the lacquer sealer. During the lacquer sealer application the front door to the house was open and the house’s windows were closed. No other ventilation was used throughout the project. The gas pilot lights for both the hot water heater and the gas furnace, both located in the closet off the living room, had not been extinguished. Prior to the incident, the co-worker had been using a brush to apply the lacquer sealer in hard to reach areas in the hallway near the bathroom. The victim had been applying the lacquer sealer in the living room with an applicator. The five gallon container of lacquer sealer was located in the living room near the victim. When the vapors from the lacquer sealer ignited it caused an explosion blowing out several of the house’s windows resulting in the house catching fire. The victim yelled “fire” and both the victim and the co-worker ran for the front door. The co-worker made it out of the house uninjured, but the victim did not make it out of the burning house.

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/08%3A_Safety_in_Leadership_and_Planning/8.01%3A_Activities-Safety_Leadership_and_Planning.txt

Thumbnail: Car Engine, attribution Paul Brennan Pixabay.com 09: Automotive-Transportation Safety Reflection: Auto Safety One of our first activities and responsibilities as adults is learning the safe use and operation of a car. Cars on the roads are expected to be safe and in good condition. While the requirements for motor vehicle safety fall under the Department of Transportation and Highway Safety there are often many workers on the 'clock' traveling on our highways at all times of the day. OSHA requires motor vehicles as transportation and equipment for conducting work related activities to be safe. Automotive shops operated commercially and as part of a company's business operations serve an important safety function, however, those same places we rely on to keep our vehicles in good working order can be very hazardous for auto technicians. Take a moment to reflect on just one of the automotive shop hazards discussed below and identify a walking-working surfaces standard that would complement a safety rule and control the associated hazard. Using the hierarchy of controls identify what type of control the standard represents. Elimination, substitution, engineering, work practice? Automotive Shop Hazards Every year, thousands of technicians are accidentally injured or killed on the job. Most of these accidents resulted from a broken safety rule. The injured persons learned to respect safety rules the hard way-by experiencing a painful injury. You must learn to respect safety rules the easy way-by studying and following the safety rules given in this section. While working, constantly think of safety. Look for unsafe work habits, unsafe equipment, and other potentials for accidents. Some areas in the automotive repair shop are more dangerous than others. Areas where dangerous equipment is used or toxic chemicals are stored are often identified by brightly colored floor markings or signs to alert employees to the potential hazards. When working in these marked safety areas, take extra precautions to prevent injury. Evacuation routes shall be posted in prominent areas throughout the shop. These routes show you how to quickly exit the building in case of a fire, gas leak, or other emergency. Always study the evacuation routes and be aware of your location in relation to these routes whenever you are working in the shop. Being able to quickly exit the building during an emergency could save your life. When working in an auto shop, you must always remember that you are surrounded by other technicians. This makes it even more important that you concentrate on safety to prevent injury to yourself and to others in the shop. Types of Accidents Basically, you should be aware of and try to prevent six kinds of accidents: • Fires • Explosions • Asphyxiation (Airborne Poisons) • Chemical Burns • Electric Shock • Physical Injuries If an accident or injury occurs in the shop, notify your instructor immediately. Fires Fires are terrible accidents capable of causing severe injury and permanent scar tissue. Therefore, every precaution must be taken to prevent fires in the automotive shop. There are numerous combustible substances (gasoline, oily rags, paints, thinners) found in an auto shop. Gasoline is by far the most dangerous and underestimated flammable substance in an auto shop. Gasoline has astonishing potential for causing a tremendous fire. Just a cupful of gasoline can instantly engulf a car in flames. A few gasoline safety rules include: • Store gasoline and other flammable substances in approved, sealed containers. • Never use gasoline as a cleaning solvent. • When disconnecting a vehicle's fuel line or hose, wrap a shop rag around the fitting to keep fuel from squirting or leaking. • Wipe up gasoline spills immediately. Do not place oil absorbent ( oil-dry) on gasoline because the absorbent will become highly flammable. • Keep any source of heat away from open or exposed fuel system parts. • Disconnect the battery or HV battery pack before working on a fuel system. Oily rags can also start fires. Soiled rags should be stored in an approved safety can. Paints, thinners, and other combustible materials should be stored in a fire cabinet. Also, never set flammable substances near a source of sparks (grinder), flames (welder or water heater), or heat (furnace, for example). Electrical fires can result when a "hot wire" (wire carrying current to component) touches ground (vehicle frame or body). The wire can heat up, melt the insulation, and burn. Then, other wires can do the same. Dozens of wires could burn up in a matter of seconds. To prevent electrical fires, always disconnect the battery when told to do so in a service manual. If possible, keep the battery disconnected during repairs. It you have been trained and authorized to use a fire extinguisher locate the fire extinguishers in your shop and use for an incipient stage fire only should one occur. Always use the recommended type of extinguisher. Using the wrong extinguisher can actually cause the flames to spread. Multipurpose fire extinguishers can be used for a variety of fires. The most common type of multipurpose extinguisher is an A, B, C, dry-chemical fire extinguisher. To use a fire extinguisher, use the PASS technique,a pull the safety pin from the handle. Aim the nozzle at the base of the flames and squeeze the extinguisher handle while sweeping from left to right Figure \(1\): Fire Safety-Extinguisher and fire classification. (Source; Greg Ling-Long Beach City College) Explosions An explosion is the rapid, almost instant, combustion of a material that causes a powerful shock wave to travel through the shop. Several types of explosions are possible in an auto repair facility. You should be aware of these sources of sudden death and injury. Hydrogen gas can surround the top of a car battery that is being charged or discharged (used). This gas is highly explosive. The slightest spark or flame can ignite the hydrogen gas, causing the battery to explode. Battery acid and pieces of the battery case can blow into your eyes and face. Blindness, facial cuts, acid burns, and scars can result. Always wear eye and face protection when working around a battery. Fuel tanks, even seemingly empty ones, can explode. A drained fuel tank can still contain fuel gum and varnish. When this gum is heated and melts, it can emit vapors that may ignite. Keep sparks and heat away from fuel tanks. When a fuel tank explodes, one side will usually blow out. Then, the tank will shoot across the shop as if shot out of a cannon. You or other workers could be killed or seriously injured. Asphyxiation Asphyxiation is caused by breathing toxic or poisonous substances. Mild cases of asphyxiation will cause dizziness, headaches, and vomiting. Severe asphyxiation can cause death. The most common cause of asphyxiation in an auto shop is the exhaust gases produced by an automobile engine. Exhaust gases are poison. If a vehicle must be operated in an enclosed shop, connect the vehicle's tailpipe to the shop's exhaust ventilation system. Also, make sure the exhaust ventilation system is turned on. If a shop exhaust system is not available use large portable fans to push air outdoors through garage doors. As discussed in related chapters, other shop substances are harmful if inhaled. A few of these harmful substances include asbestos (brake lining dust, clutch disc dust), parts cleaners, and paint spray. Wear appropriate PPE when handling these parts or materials. Respirators (filter masks) should be worn when working around any airborne impurities. Dust masks are made of treated paper and will only stop large particles from entering your body. Cartridge respirators provide good respiratory protection when potentially hazardous fumes are present in the shop. An air-supplied respirator must be worn when catalyzed paint products are applied in the shop. Chemical Burns Solvents (parts cleaners), battery acid, and various other corrosive shop substances can cause chemical burns to the skin. Always read the directions on all chemical containers. Also, be sure to wear proper protective gear when handling solvents and other caustic materials. Throttle body cleaner (decarbonizing type), for example, is very powerful and can severely burn your skin in a matter of seconds. Wear rubber gloves and a full face shield when using a decarbonizing throttle body cleaner. If a skin or eye burn occurs, follow label directions. Electric Shock Electric shock is a result of electric current passing through parts of your body, causing injury or death. It can occur when using improperly grounded electric power tools. Never use an electric tool unless it has a functional ground prong (third, round prong on plug socket). This prevents current from accidentally passing through your body. Also, never use an electric tool on a wet shop floor. Hybrid Safety Hybrid vehicles use a high-voltage motor/generator and an HV battery pack that operates on approximately 300-600 volts. This is enough electrical energy to cause serious injury or even electrocution! Voltage levels and hybrid service procedures vary. Therefore, it is important to follow the vehicle manufacturer's instructions and safety rules when working on a specific make and model hybrid. Always wear rubber electrician's gloves (rated for 1000 volts) when working on a high-voltage hybrid drive train system. The thick rubber gloves will prevent electric shock if you accidentally touch a conductor carrying high voltage and current. You must also use fully insulated tools to service the high-power cable connections on the battery. Most hybrids have a main power cutoff switch, or high-voltage disconnect, near the output cables of the battery pack. This switch allows you to electrically disconnect the battery pack from the rest of the hybrid drive train system. It should be turned to the off or disabled position before servicing a hybrid drive train system. Physical Injury Physical injuries such as cuts, broken bones, strained backs can result from many situations in an auto shop. As a technician, you must evaluate every repair technique. Decide whether a particular operation is safe and take action as required. For instance, if you are pulling on a hand wrench as hard as you can and the bolt will not turn, stop! Find another wrench that is larger. A larger tool has more leverage and is, therefore, safer. This approach will help prevent injuries and improve your mechanical abilities. Flash Cards - Key Terms and Definitions This interactive feature not available in print version of this workbook Video - Auto Shop Safety Automotive Skills Center Intro and Safety 2 Transcript Automotive Shop Safety Transcript Standard Mapping - Identify Overlapping Standards for Automotive Safety Working in the automotive shop is a hazardous environment which requires safety to avoid injury or possible death. As a technician, you will be working with tools and equipment to service and repair vehicles. In this activity you will map automotive safety standards to specific safety warnings and procedures for working in the automotive shop. Standard Mapping Table General Industry Stardard Subpart Section Shop Safety Warning, Rule, Procedure, Hazard 1910 Subpart E - Exit Routes and Emergency Planning 1910.34 - Coverage and definitions 1910 Subpart G - Occupational Health and Environmental Control 1910.94 - Ventilation 1910 Subpart H - Hazardous Materials 1910.106 - Flammable liquids 1910 Subpart I - Personal Protective Equipment 1910.132 - General requirements 1910 Subpart I - Personal Protective Equipment 1910.133 - Eye and face protection 1910 Subpart I - Personal Protective Equipment 1910.134 - Respiratory Protection 1910 Subpart K - Medical and First Aid 1910.151 - Medical services and first aid 1910 Subpart L - Fire Protection 1910.157 - Portable fire extinguishers 1910 Subpart L - Fire Protection 1910.165 - Employee alarm systems 1910 Subpart M - Compressed Gas and Compressed Air Equipment 1910.169 - Air receivers 1910 Subpart N - Materials Handling and Storage 1910.179 - Overhead and gantry cranes 1910 Subpart O - Machinery and Machine Guarding 1910.212 - General requirements for all machines 1910 Subpart O - Machinery and Machine Guarding 1910.217 - Mechanical power presses 1910 Subpart P - Hand and Portable Powered Tools and Other Hand-Held Equipment 1910.242 - Hand and portable powered tools and equipment, general 1910 Subpart S - Electrical 1910.304 - Wiring design and protection Case Study – Fatality Discuss in your group the specifics of the case below. The details are summarized. View the figures in the report showing the layout of the shop, the vehicle, and employee workstation. Discuss in your groups how you would have prevented this incident. Consider creating a JHA to support your case. Next given the following from the incident report: Recommendation No. 2: All duties and other tasks not involving the driver of the vehicle, should be performed in an area away from or barricaded from contact with vehicles being serviced. Are there existing standards that mitigate or are a work around for poor shop design? What are they and how would you implement? Incident Number: 14KY001 Pedal for Brake Pedal and Fatally Pins Co-Worker Summary Monday, January 06, 2014, the Kentucky Fatality Assessment and Control Evaluation program was notified by a local news channel of a fatality at a dealership involving a vehicle and an employee. The local news reported that the employee was struck from behind while sitting at his desk in the bay area, with his back to the service area, where a technician attempted to idle a vehicle to proceed with an oil change. The technician accidently mistook the handicapped accelerator pedal for the brake pedal and the vehicle traveled into the desk area where the victim was sitting. The technician desperately tried to veer to the right when he realized what was happening but was unable to avoid striking the chair where the victim was sitting and shoved the victim into the desk and wall. Investigation Details Monday, January 6, 2014, a 50-year-old Master Technician and married father spoke to another technician about work that needed to be done to a 2009 Lincoln MKX that was accessible for a handicapped driver with a left-foot accelerator made for people who have lost the ability to use their right foot. The left foot gas pedal was purchased from Mobility Products & Design and was model number 3545. This model type is easily removable. To remove the left-foot accelerator you lift the key ring on the LFGP (left foot gas pedal) assembly and while lifting and holding the key ring up, slide the lockout base to the left. When the assembly begins to move, release the key ring and continue to slide the assembly left until it can be lifted out of the base. The instructions are easy to follow and should be placed on the dash where other operators are aware of the installation of handicapped equipment. Mobility Products and Design includes a sticker with their products to be installed on the dash board for safety purposes. The sticker was not on the dash as per instructions of Mobility Products and Design. After agreeing on the work that needed to be completed, the victim moved to his desk area in front of the bay area where the vehicle was going to be serviced. The Master Technician sat at his desk with his back towards the service area. The technician started the vehicle and while idling, he engaged what he thought was the brake. However, it was the handicapped equipped accelerator and it caused the vehicle to travel forward striking the chair of the victim and pinning him between the desk and the vehicle. Interviews with the employees discovered there was a prior handicapped vehicle that came in for service and the handicapped equipment was removed prior to the technician’s operation of the vehicle. However, this time, the handicapped equipment was not removed even though the technician was not trained to operate handicapped equipment. It is unknown why the handicapped equipment was not removed and a warning sticker was not on the dash board of the vehicle. Cause of Death The cause of death was multiple blunt force injuries from being pinned between the car and the desk and wall.

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/09%3A_Automotive-Transportation_Safety/9.01%3A_Auto_Lab.txt

Reflection: Auto Shop Equipment Vehicles are used in everyday life as people drive to work, to see family, or just for the enjoyment of travel. In order for vehicles to be road-worthy, they must be in top operating condition. Failure of any vehicle’s component or system may result in injury or even death. Auto technicians receive vehicles brought in for routine maintenance and/or service. Technicians in automotive shops when servicing vehicles utilize numerous equipment that must be routinely inspected, operated correctly and safely. Review the Automotive Shop Equipment discussed below and identify the standard that would compliment a safety protocol for the safe use of that equipment. Considering the hierarchy of controls what type of control is it? Reference workbook section 7: Tools and Equipment-Industrial Safety and Manufacturing and textbook chapter 12: Crane and Hoists for insight. Automotive Shop Equipment-Hazards There are several different areas in an auto shop. You must describe the areas by name and understand the basic rules that apply to each. It is important that you learn your shop layout and organization to improve work efficiency and safety. The auto shop includes the following work areas: • Repair area • Tool room • Classroom Repair Area The repair area includes any location in the shop where repair operations are performed, such as in the shop stall, lift, alignment rack, and outside work area. It normally includes every area except the classroom, locker room, and tool room. Shop Stall A shop stall is a small work area where a vehicle can be parked for repairs. Sometimes, each stall is numbered and marked off with lines painted on the floor. Some auto shop facilities have an outside work area adjacent to the garage overhead doors. In good weather, this area can be used for auto repairs. Always raise the shop doors all the way and pull cars through the doors very slowly. Lift The lift is used to raise a vehicle into the air. It is necessary for working under the car (draining oil, greasing front end ball sockets, or repairing exhaust systems). Remember these lift safety steps: 1. Ask your instructor for a demonstration and get permission before using the lift. You must be trained and authorized to use the lift. 2. Always read manufacturer's operating instructions closely before using a lift. If a lift lowers a car on someone, they will likely be crushed and killed instantly. A-Most lifts have a mechanical safety catch. A large metal lug must be engaged fully into the metal post before working under the vehicle. Without the mechanical catch engaged, a hydraulic failure could make the vehicle drop instantly to the ground with deadly crushing force. 3. Inspect the lift, the floor area around the lift. 4. Position the vehicle's center of gravity (point of perfect balance) on the lift as described in the vehicle service manual. If a front-engine vehicle or a pickup truck with no weight in the bed, position the lift arms (if applicable) more to the front of the chassis. In a mid- or rear-engine car, place the lift pads more to the rear so the car will not slide or tilt off the lift. 5. Raise vehicle slowly while keeping your fingers away from any moving parts on the lift. Raise the car about one inch off the ground. Double check your lift points and make sure the vehicle is perfectly level. Always place your head next to the shop floor so you can see the alignment of the liftpad and vehicle pinch welds or frame rails. 6. When the vehicle is high enough to be worked on, make sure the lift's mechanical safety catch is engaged. Do not walk under the lift without the catch in the fully locked position Figure \(1\): Diagram of Lift. (Source; Greg Ling-Long Beach City College) Alignment Rack The alignment rack is used when working on a car's steering and suspension systems. It may contain a special tool board and equipment used when replacing worn suspension and steering parts, or adjusting wheel alignment. When using an alignment rack, the car should be pulled onto the rack slowly and carefully. Someone should guide the driver and help keep the tires centered on the rack. As with other complicated and potentially dangerous equipment, obtain a full demonstration before using the alignment rack. Tool room The tool room is a shop area where larger pieces of repair equipment are stored. The tool room is used to store shop tools, small equipment, and supplies, such as nuts, bolts, and oil. It is normally located adjacent to (next to) the repair area or classroom. When working in the tool room, you will be responsible for keeping track of shop tools. Every tool checked out of the tool room must be recorded and called in or retrieved before the end of the class period. Normally, the tools hang on the walls of the tool room for easy access. Each tool may have a painted silhouette, which indicates where it should be kept. Your instructor will detail specific tool room policies and procedures. Classroom / Training Room The classroom is usually an office-like area in a school or large repair facility, where students or mechanics can meet to increase their knowledge of auto service and repair. Either a certified instructor or the service manager presents the information to the students or experienced technicians. The classroom is used for seminars, demonstrations, and other technician training activities. It is often located adjacent to the repair area. Follow all posted safety rules for the classroom. Flash Card-Key terms and Definitions This interactive feature not available in print version of this workbook Standard Mapping - Identify Overlapping Standards for Automotive Safety Working in the automotive shop is a hazardous environment which requires safety to avoid injury or possible death. As a technician, you will be working with tools and equipment to service and repair vehicles. In this activity you will map the requirements for tool and equipment safety and specific safety warnings and procedures to safety standards to OSHA safety standards applicable to shop safety. Standard Mapping Table Standard Mapping Table General Industry Standard Subpart Section Shop Equipment or tool Safety Warning, Safety Procedure 1910 Subpart F – Powered Platforms, Manlifts, and Vehicle-Mounted Work Platforms 1910.67 – Vehicle-Mounted elevating and rotating work platforms 1910 Subpart H - Hazardous Materials 1910.106 - Flammable liquids 1910 Subpart I - Personal Protective Equipment 1910.132 - General requirements 1910 Subpart I - Personal Protective Equipment 1910.133 - Eye and face protection 1910 Subpart I - Personal Protective Equipment 1910.134 - Respiratory Protection 1910 Subpart I - Personal Protective Equipment 1910.138 - Hand Protection 1910 Subpart K - Medical and First Aid 1910.151 - Medical services and first aid 1910 Subpart L - Fire Protection 1910.157 - Portable fire extinguishers 1910 Subpart L - Fire Protection 1910.165 - Employee alarm systems 1910 Subpart N - Materials Handling and Storage 1910.179 - Overhead and gantry cranes 1910 Subpart O - Machinery and Machine Guarding 1910.212 - General requirements for all machines 1910 Subpart O - Machinery and Machine Guarding 1910.217 - Mechanical power presses 1910 Subpart P - Hand and Portable Powered Tools and Other Hand-Held Equipment 1910.242 - Hand and portable powered tools and equipment, general Video-Equipment Safety How to use 2-post Lift Transcript How it works?!? The CAR WIZARD shows how to operate a two-post car lift. Transcript Vehicle Lift Failures Case Study – Fatality Discuss in your group the specifics of the case below. The details are summarized. View the figures in the report showing the shop equipment and usage of the vehicle lift. Discuss in your groups how you would have prevented this incident. Consider creating a JHA to support your case. Are there any standards that mitigate or are a work around for servicing a vehicle while on a lift? What are they and how would you implement? Vehicle Fell From Auto Lift, Mechanic Crushed Under Auto Incident Number: 14543334 Accident detail Introduction Employee #1, A mechanic, was repairing a tie-rod on a vehicle which was suspended over his head on an auto lift. He inadvertently struck the lift securing pad with his hammer, causing the telescoping movable securing lift arm to move. The vehicle fell from the auto lift to the garage floor. The mechanic was caught under the falling car and crushed to death. The auto lift was manufactured by The Dover Corp., Rotary Lift Division. The auto lift's ID number was E770 3022M; serial number 0500, part number P451. The lift’s model number was AB00137-SP80 MARK II. It had a 7,000 pound lift capacity. The manufacturer’s lift instructions were not followed during installation of the auto lift. Employer: Gronski Enterprises 3905 Birney Avenue Scranton, PA 18505 9.A: Auto Shop Images Working and Walking Surfaces Walkways Query \(4\)

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/09%3A_Automotive-Transportation_Safety/9.02%3A_Auto_Lab_Equipment_Safety.txt

IT'S YOUR TURN Thumbnail: Image attribution, Titiana Tickhnova, Pixabay.com 10: Welding Safety Reflection: Remember that sunburn? Read the article linked below and discuss with your peers the specific health hazards associated with welding. Categorize the symptoms associated with the health hazards or risks as either acute or chronic. What are the required PPE? https://www.weldingboss.com/can-you-get-sunburned-from-welding/ Flash Cards: Definitions and key terms This interactive feature not available in print version of this workbook Hazards/Hazard Recognition Welding is an extremely hazardous activity requiring skill and focus to complete safely. The Arc Welding Safety Guide is a comprehensive tutorial for Arc Welding and is provided as a reference resource along with the AWS/ANSI Welding Safety Standard PowerPoint and the Safe Working Conditions PowerPoint. Use the Welding Process Hazard Flowchart and map to the Welding Safety Inspection Checklist. Can you think of a non-welding safety standard that could be included in the checklist? Standard Mapping-Identify overlapping standards for welding safety Welding is an extremely hazardous activity. There are many organizations who provide overside, guidance, design and safety protocols for welding safety. OSHA incorporates by reference and relies on the welding industry to establish safety standards. In the exercise below map two safety protocols from sections 3, 4, 5, 6, 7 from ANSI Z49.1 for each subpart listed. Mapping Overlapping Standards for Welding OSHA Subpart ANSI Z49.1 Safety in Welding, Cutting, Allied Processes-Section number and safety protocol. (2 for each, preferrably different sections) Subpart D – Walking-Working Surfaces Subpart E – Means of Egress Subpart G – Occupational Health and Environmental Control Subpart H- Hazardous Materials Subpart I – Personal Protective Equipment Subpart J- General Environmental Controls Subpart K- Medical and First Aid Subpart L – Fire Protection Subpart M – Compressed Gas and Compressed Air Equipment Subpart Q- Welding, Cutting, and Brazing Subpart S – Electrical Subpart J - Welding and Cutting (1926) Welding and Hazardous Materials Use the following resources to complete the associated activity after viewing video on welding safety. Case study-Map Corrective Actions Map the corrective actions identified in the case study to a specific safety standard that is either an engineering, work practice, or PPE control. What were the actual hazards present during or before the event? Cite one or two of the seven common accident causes that contributed to this event. Welding Eye Injury Case study- Shipyard death Instructions: As a group review the case study of the Shipyard welder PDF provided. Address in the following recommendations two safety facts from the Whip Around Activity for each recommendation proposed. Recommendations: 1. Employers and employees should assure that equipment is appropriate for the task and maintained to manufacturer’s specifications. 2. Daily checks of all hydraulic equipment should include inspection of hydraulic hoses and connections. 3. Hydraulic lines should be relocated and protected from physical damage. 4. Check all safety equipment and ensure that it is operational, appropriate for the task and that employees know and understand how to use it. 5. Employers should maintain a current list and copy of SDS’s for the chemicals in use in the work place, and employees should be appropriately equipped and trained for emergency response. Welding Case Study - Shipyard Welder 10.02: Shop set up safety assessments and exam prep-study guides equipment checklists Shop set up, safety assessments The following accessible links cover welding lab/shop safety. National Center for Construction Education and Research NCCER’s four-level curriculum covers topics such as Oxyfuel Cutting, Welding Symbols, and Stainless Steel Groove Welds. NCCER’s curriculum also correlates to the AWS SENSE (Schools Excelling through national Skills Education) standards and guidelines for Entry Welder. OSHA 10 in the Construction Industry, NCCER Core Curriculum, NCCER Welding Level I Based on the ANSI Z49.1:2012 Safety in Welding Standard, this course includes a broad range of topics, including hazards, safety equipment, ventilation, welding in confined spaces, safety precautions, and safety specifications. Want to know more? Presented in easy-to-access, online modules, the AWS Safety in Welding course is equally accessible to students, hobbyists and established professionals who want to expand their knowledge base and core competencies. SAFETY IN WELDING - Welding Safety Course (Free Version) The AWS Safety in Welding Course is now FREE! WITH ACCESS TO MORE INFO THAN EVER > 11 Modules with Pre & Post Quizzes ANSI Z49.1 National Standard Safety & Health Fact Sheets The American Welding Society is accredited by the International Association for Continuing Education and Training (IACET) and is accredited to issue the IACET CEU 10.03: Resources 1. Lincoln Global (2022, Feb). SAFE-SAFEWORK-LP.pdf Retrieved from https://www.lincolnelectric.com/assets/US/EN/Extranet/pdfs/education/SAFE-SAFEWORK-LP.pdf 2. Lincoln Global, (2022, Feb). SAFE-AWS-ANSISTANDARD-LP.pdf Retrieved from https://www.lincolnelectric.com/assets/US/EN/Extranet/pdfs/education/SAFE-AWS-ANSISTAND 3. OSHA Construction worker Pocket Guide 4. ARD-LP.pdf 5. American Welding Society, (2022, Feb). SAFETY IN WELDING Retrieved from https://awo.aws.org/online-courses/safety-in-welding/ 6. American National Standard Committee Z49, (2022, Feb). Safety in Welding, Cutting, and Allied Processes. Retrieved from https://awo.aws.org/wp-content/uploads/2015/10/AWS_Z49.pdf

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/10%3A_Welding_Safety/10.01%3A_Lab-Welding_Safety.txt

Thumbnail: Attribution, Green Chameleon Usplash 11: Topic Quiz 1. OSHA's mission is to: a. Protect the safety and health of the general public. b. Protect the safety and health of America's workers, c. Ensure that all workers receive the federal minimum wage, d. Ensure that all workers receive adequate workers' compensation payments. 2. The creation of OSHA provided this important right to workers: a. The right to equal employment opportunities, b. The right to privacy, c. The right to pension benefits. d. The right to a safe and healthful workplace. 3. A Safety Data Sheet (SDS) gives information about: a. Hazardous chemicals, b. Injuries in the workplace, c. Medical examinations, d. Machinery maintenance. 4. Among the rights related to OSHA recordkeeping, workers have the right to review: a. All first aid treatment forms. b. All Workers Compensation forms. c. The OSHA 300 Log and the OSHA 300A Summary. d. Medical and exposure records for all workers. 5. During an OSHA inspection: a. Worker representatives are not permitted to accompany the inspector, b. You may not describe safety and health concerns you have to the inspector, c. Employers determine which workers are interviewed. d. You have the right to talk to the inspector privately. 6. The right of workers to seek safety and health on the job without fear of punishment is spelled out in: a. State laws, b. The OSHA standards. c. Section ll(c) of the OSH Act. d. The General Duty Clause. 7. One of the main responsibilities employers have under OSHA is to: a. Provide training required by OSHA standards. b. Reduce air pollution in the environment. c. Conduct energy audits. d. Notify OSHA of any workplace injury or illness. 8. OSHA requires that employers pay for most required personal protective equipment (PPE), including: a. Uniforms. b. Logging boots. c. Hard hats. d. Weather-related gear. 9. The OSHA standards for Construction and General Industry are also known as: a. Part 1926 and Part 1910. b. Part 1915 and Part 1917. c. Codes 501 through 1000. d. Construction and GI Registers. 10. What type of OSHA inspection is conducted when immediate death or serious harm is likely? a. Complaint. b. Programmed. c. Referral. d. Imminent danger. 11. When the employer receives an OSHA citation, it must be: a. Copied and mailed to each worker. b. Posted for 3 days or until the violation is fixed. c. Contested and filed with the courts. d. Signed and returned to OSHA. 12. If you feel that an OSHA inspection is needed to get hazards corrected at your workplace, which is your best option? a. File a complaint online. b. Submit a written, signed complaint with specific hazard information. c. Request a Health Hazard Evaluation from NIOSH. d. Submit an unsigned complaint form to OSHA. 11.02: Quiz 1-Safety Orientation in Construction Environments 1. True or False... The residual effects of a substance such as alcohol or marijuana can cause someone to have an accident hours or even days after they last used the substance? 2. True or False... Most hazards can be spotted and eliminated before they become a problem? 3. True or False... You should never use more than one type of hearing protection (such as ear plugs, canal caps or earmuffs) at the same time? 4. Which of the following can be potential source of ignition and fires? 1. A. Sparks from power tools. 2. B. Damaged electrical cords. 3. C. Piles of cardboard. 4. D. All of the above. 5. True or False... Most tasks have multiple hazards associated with them? 6. True or False... You should keep your body in "neutral" positions as much as possible as you go through your workday? 7. True or False... Most safety shoes have soles that are designed to work in specific types of conditions? 11.03: Quiz 2-Safety Housekeeping and Accident Prevention TRUE OR FALSE 1. True or False...Even though many jobs are different, there are common safety practices we should follow in all of them? 2. True or False... No matter how much work we have to get out, sometimes we need to take "breaks" to avoid mental or physical stres 3. True or False...When you are pressed for time, the best thing to do is to improvise with your tools, such as using a screwdriver as a chisel? 4. True or False... It is all right to store food or drink next to chemicals, as long as the area is refrigerated 5. True or False...As long as the shelving is rated for the containers' total weight, it doesn't matter what chemicals are stored next to each other? 6. True or False...A dull knife is more dangerous than a sharp one? MULTIPLE CHOICE 1. The abbreviation SDS stands for…? ________Security data storage ________Source definition sheet. ________Safety Data Sheet. 11.04: Quiz 3-Bloodborne Pathogens in Commercial and Light Industrial Facilities 1. Which of the following are the two most prevalent blood borne diseases in the United States? ________Hepatitis B. ________HIV. ________Tuberculosis. ________Mononucleosis. 2. Approximately how many new cases of Hepatitis B occur in the United States each year? ________70,000. ________300,000. ________3 million. 3. True or False... Vaccines do exist that can prevent infection from Hepatitis C and HIV? 4. What is the most important personal hygiene practice for preventing infection from blood borne diseases? ________Cleaning fingernails daily. ________Hand washing. ________Gargling with disinfectant. 5. What color must be used as the "background" on biohazard warning labels? ________Yellow. ________Red/orange. ________Black. 6. True or False... All types of gloves can be reused after an exposure incident if they are decontaminated? 7. True or False... Personal protective equipment can help guard against infection by blood borne pathogens? 11.05: Quiz 4-Right to Know for Building and Construction Companies 1. Which of the following information can you find on a chemical's Material Safety Data Sheet? ________Chemical name. ________Potential hazards. ________Cleanup procedures. ________Recommended PPE. ________All of the above. 2. Which type of chemical is generally considered to be the most hazardous? ________Corrosive. ________Irritant. 3. True or False... Most chemicals do not burn in their liquid state. It is really their vapors that burn? 4. True or False... All toxins are poisons? 5. What is the health hazard most associated with corrosive chemicals? ________Nausea. ________Burns. ________Shock. 6. What is the term used for how chemicals enter the body? ________Methods of absorption. ________Routes of entry. ________Paths of infection. 7. What is the term for a cancer-causing chemical? ________Hemoglobin. ________Carcinogen. 11.06: Quiz 5-Forklift Powered Industrial Truck Safety 1. True or False... Only fully trained personnel are authorized to operate powered industrial trucks? 2. True or False... All forklifts are built to handle loads of any size and weight? 3. Which of the following entries would you expect to find on an equipment checklist for an electric (battery powered) forklift? ________Electrolyte level. ________Oil. ________Coolant. 4. True or False... When driving on a slope you should keep the back of a loaded forklift pointed "uphill"? 5. True or False... When driving with an empty forklift, forks should be kept 18 to 24 inches off the ground? 6. True or False... The safest way to cross curbs and railroad tracks with a powered industrial truck is at an angle? 7. True or False... When working with pallets, a forklift's forks should be positioned as widely apart as possible?

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/11%3A_Topic_Quiz/11.01%3A_Quiz_0-Check_Yourself.txt

1. True or False... Leather or metal mesh gloves provide the best protection when working with sharp edges? 2. Soft rubber-soled safety shoes are best on what types of surfaces? ________Concrete. ________ Dry surfaces. ________Wet wood. 3. True or False... In most cases hard hats and bump caps are interchangeable? 4. The best protection from chemical splashes is? ________Safety glasses. ________Goggles. ________Visors. 5. The initials SCBA stand for what? ________Safety-contained breathing air. ________Scrubbed chemical breathable air. ________Self-contained breathing apparatus. 6. Air filter cartridges are labeled and color-coded to provide what information? ________What model of respirator they can be used with. ________What substances they filter out. 11.08: Quiz 7-Fall Protection in Construction Environments 1. True or False... The "three-point climb" is recommended when using ladders? 2. True or False... When using lift buckets, extra protection is not required? 3. Fall protection equipment does not include which of the following? ________Guard rails. ________Safety nets. ________Personal fall arrest systems. ________Safety glasses. 4. True or False... Guard rails must support at least 1,000 pounds? 5. True or False... Wearing a full body harness provides adequate support during a fall? 6. True or False... Bosun's chairs are only used on ships? 7. To be safe, an anchor point has to support how much weight per person? ________1,000 pounds. ________3,000 pounds. ________5000 pounds. 11.09: Quiz 8-Confined Space Entry 1. Which of the following are considered to be confined spaces? ________Tanks. ________Vessels. ________Hoppers. ________Vaults. ________Trenches. ________Silos. ________All of the above. 2. True or False... "engulfment" is a type of hazard that may be found in a confined space? 3. True or False... According to OSHA there can be too much, as well as too little, oxygen in a confined space? 4. When testing a confined space for atmospheric hazards, what should be tested for first? ________Flammable gases. ________Vapors and dust. ________Oxygen content. ________Toxic contaminants. 5. True or False... Forced-air ventilation alone can always protect entrants from toxic gases? 6. True or False... Normally an attendant is not allowed to enter a confined space? 7. True or False... An entry supervisor must sign an entry permit before work can begin in a confined space? 11.10: Quiz 9-Supported Scaffolding Safety in Construction Environments 1. True or False... OSHA estimates that approximately 10,000 scaffold-related injuries occur every year? 2. Which of the following types of supports are used in building supported scaffolds? ________Poles. ________Frames. ________Posts. ________All of the above. 3. True or False... OSHA requires that a "scaffold expert" be on site only during the initial assembly of a scaffold? 4. True or False... The "maximum intended load" of a scaffold includes the total weight of all workers, as well as their equipment, tools and materials? 5. True or False... When you are erecting a scaffold, it is permissible to use cinder blocks for support? 6. True or False... You should never use a platform or a plank that has a painted walking surface? 7. True or False... OSHA does not require that safety rails be used on all scaffold stairway towers, only certain types? 11.11: Quiz 10-Crane Safety in Construction Environments 1. True or False... It is critical to know the weight capacity of a crane before hoisting a load? 2. Which of the following is not a type of industrial crane? ________Boom. ________Jib. ________ Barrel. ________Overhead. 3. True or False... When performing an inspection of a crane, it is not necessary to check fluid levels to see if they are within acceptable limits? 4. True or False... Every boom crane has its own load chart? 5. Which of the following operational safety devices does not monitor and/or control the handling capabilities of a crane? ________Overload indicators. ________Emergency stop buttons. ________Anti-slip bevels. ________Limit switches. 6. True or False... To signal an "emergency stop", extend both of your arms out (with palms down) and move them horizontally? 11.12: Quiz 11-Powdered Actuated Tools 1. True or False...Only powder actuated tools that meet the design requirements of ANSI or local state approved codes may be used. 2. True or False... In some states, no one under the age of 21 is permitted to operate powder actuated tools. 3. True or False...Only approved "pole tool assemblies" should be used. 4. True or False... It is okay for fasteners to be driven into hard or brittle materials. 5. True or False...Powder actuated tools and power loads shall be locked in a container and stored in a safe place when not in use. MULTIPLE CHOICE 6. Operator's cards and/or permits are issued by: a. a supervisor b. ANSI c. a qualified instructor d. OSHA 7. Each tool shall be accompanied with: a. an operator's instruction manual b. tool inspection and service record c. power load and fastener chart d. all of the above 8. Fasteners shall not be driven closer than________inch from the edge of steel except for specific applications recommended by the tool manufacturer. a. 1/4 b. 1/8 c. 1/2 d. 1 9. The tool should always be held________to the work surface when fastening into any material. a. firmly b. straight c. perpendicular d. horizontal 10. A sign at least________using boldface type no less than one inch in height must be conspicuously posted within 50 feet of the area where the tools are being used. a. 5x7 b. 8x10 c. 10x12 d. 12x15 11.13: Quiz 12-Portable Grinding and Abrasive Wheels 1. True or False...Abrasive wheels should be stored according to type, size and speed with all bins clearly marked. 2. True or False...The smallest crack in the abrasive wheel or disk will not create a problem when the wheel is used. 3. True or False...The blotter on every grinding wheel provides the manufacturer's recommended minimum operating speed. 4. True or False...Before installing a new wheel on the grinder, inspect it carefully even though it looks good. 5. True or False...The ring test on a wheel includes suspending the wheel with your finger and tapping it with an object such as a wooden screwdriver and listening for a bell-like ring or tone. MULTIPLE CHOICE 6. To properly mount the wheel on the grinder, you should make sure________. a. wheel and mounting flanges must be clean b. never use a straight wheel without blotters c. the arbor shank should extend through the wheel d. a, b, and c 7. The tool rest should be positioned________of an inch from the wheel. a. 1/4 b. 1/2 c. 3/8 d. 1/8 8. Abrasive wheels get extremely hot. Grinding should not be made on: a. glass b. steel c. all soft metals d. none of the above 9. Grinder operators should wear personal protective equipment such as: a. safety glasses b. face shields c. hard hat d. a & b

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/11%3A_Topic_Quiz/11.07%3A_Quiz_6-Personal_Protective_Equipment_in_Construction_Environments.txt

1. True or False... The "force" carried by electricity is measured in "volts"? 2. True or False... It is "amps" (the intensity of current) which deliver electric shocks, not volts 3. How many "amps" can most household and industrial lines safely carry?________ 4. True or False.... 0.06 amps (the amount of electricity needed to light a Christmas tree bulb) can be fatal? 5. True or False.... If you are using a "three-prong" outlet, you can be sure that it is"grounded"? 6. True or False.... If one of the fuses in a fuse box is continually burning out, you should replace it with a higher rated fuse? 7. True or False.... If electrical equipment is running when a leak of a flammable gas or vapor develops in your work area, you should immediately turn the equipment off? 11.15: Quiz 14-Ground Fault Circuit Interrupter 1. True or False...Conductor insulation may be provided by placing non-conductive material such as rubber tape around the conductor. 2. True or False...Metal enclosures and containers are usually grounded by connecting them with a wire going to ground. 3. True or False...The ground fault circuit interrupter is a fast-acting circuit breaker which senses small imbalances in the circuit caused by current leakage to ground and in a fraction of a second, shuts off the electricity. 4. True or False...Double insulation may be used as additional protection on the live parts of a tool. Double insulation provides protection against defective cords and plugs or against heavy moisture conditions. 5. True or False...Whenever the amount of current is "going" differs from the amount "returning" by approximately 5 milliamps, the GFCI interrupts the electric power. MULTIPLE CHOICE 6. The________ will not protect a person from line to line contact hazards such as a person holding two hot wires or a hot and a neutral wire in each hand. a. double-insulated plug b. conductors c. GFCI d. metal enclosure 7. When a cord connector is wet, ________can occur to the equipment grounding conductor and to humans who pick up the connector if they also provide a path to ground. a. shock b. hazardous leakage c. grounding d. deficiencies 8. ________can be used successfully to reduce electrical hazards on construction sites. a. GFCIs b. flex cord c. connector d. receptacle 9. Ground fault circuit interrupters must be provided for all________volt, single phase, 15 and 20 amp receptacle outlets on construction sites. a. 100 b. 110 c. 120 d. 130 11.16: Quiz 15-Trenching and Shorting 1. True or False...Planning for safety begins after the bidding process on a project. 2. True or False...If underground utilities are encountered in digging, the contactor must contact the utility company and inform them of the work to be done. 3. True or False...A trench is referred to as a wide excavation in which the depth is smaller than the width. 4. True or False...An excavation is any man-made cavity or depression in the earth's surface. 5. True or False...It is dangerous to allow trenches to remain not shored even if no work is being done on them. MULTIPLE CHOICE 6. Current OSHA regulations require that all excavations over ________feet deep be sloped, shored, sheeted, braced or otherwise supported. a. 2 b. 3 c. 4 d. 5 7. "Angle of repose" is a method of ensuring safety in an excavation or trench by sloping the sides of the cut, to the angle of repose which is the angle closest to the ________at which the soil will remain at rest. a. horizontal b. perpendicular c. middle d. edge 8. A________must determine the proper angle of repose for the specific type of soil condition. a. construction supervisor b. mechanic c. qualified engineer d. all of the above 9. In installing the shoring, care must be taken to place the crossbeams in true horizontal position and to space them________at appropriate intervals. a. horizontally b. vertically c. perpendicular d. none of the above 10. When employees are required to be in trenches 5 feet deep or more, adequate means of exit such as a ladder or steps be provided and located so as to require no more than________ feet lateral travel. a. 10 b. 15 c. 20 d. 25

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/11%3A_Topic_Quiz/11.14%3A_Quiz_13-Electrical_Safety.txt

Indicate whether the statement is true or false. ________1. The purpose of the Hazard Communication Standard was to ensure that the hazards of all chemicals produced or imported into this country are evaluated and that information regarding any health hazards be transmitted to employers and their employees. ________2. OSHA requires that employers provide employees with effective training on the hazardous chemicals in their work places within 6 months of their initial assignment, and whenever new hazardous materials are introduced into the work place. Multiple Choice Identify the choice that best completes the statement or answers the question. 3. When employees are subjected to sound levels exceeding________DBA for 8 hours, feasible administrative or engineering controls shall be utilized to protect against hearing loss. a. 115 b. 92 c. 90 d. 95 4. Only _ _ and trained employees shall be assigned to install, adjust, and operate laser equipment. a. competent b. qualified c. certified d. None of the above 5. Employers shall develop, implement and maintain at each workplace, a written Hazard Communication Program consisting of which of the following elements: a. Labels and other forms of warning. b. SDS c. Employee training and information. d. List of known hazardous chemicals at workplace.e. Methods used to inform employees of hazards. f. All of the above. 6. Means of________shall be continually maintained free of all obstructions or impediments to full instant use in the case of fire or other emergency. a. Exit b. Egress c. Entry d. Openings Multiple Response Identify one or more choices that best complete the statement or answer the question. 7. Under the provisions of Subpart C, every employer must ensure that each employee does not work under conditions which are ________or otherwise dangerous to their safely or health, a. unclean b. hazardous c. unsanitary e. Both a and d d. unhealthful f. Both b and c 8. Which of the following construction areas are required to be lit with either natural or artificial lighting during construction period? a. Aisles b. Storage areas c. Ramps d. Runways e. All areas Completion Complete each statement. 9. Name the three means that the Hazard Communication standard uses to get information about health hazards into the hands of employers and their employees. 10. Define a competent person. 11. For the purposes of Subpart C, Define a confined space. 11.18: Quiz 17-Materials Handling Storage Use Disposal Indicate whether the statement is true or false. ________1. All scrap lumber, waste material, and rubbish shall be removed from the immediate work area as the work progresses if you have employees available and capable lo do the work. Complete each statement. 2. All materials stored in tiers shall be________, racked,________, interlocked, or otherwise secured to prevent sliding, falling or collapse. Standard________. 3. ________ and ________shall be kept clear to provide for the free and safe movement of material handling equipment or employees. Such areas shall be kept in good repair. Standard________. 4. Brick stacks shall not be higher than ________ feet. What has to happen after 4 feet if the stack is loose?________ Standard________. 5. According to Standard 1926.251 (a)(l). How often shall rigging equipment for material handling be inspected? ________ 6. According to Standard 1926.252(e). Where shall oily rags be kept until they are removed from the job?________ 11.19: Quiz 18-Stairways and Ladders Indicate whether the statement is true or false. ________1. When a building or structure has only one point of access between levels, that point of access shall be kept clear to permit free passage of employees. When work must be performed or equipment must be used such that free passage at that point of access is restricted, a second point of access shall be provided and used. ________2. Stairways that will be a permanent part of the structure on which construction work is being performed shall have landings of not less than 30 inches in the direction of travel and extend at least 22 inches in width at every 12 feet or less of vertical rise. Identify the choice that best completes the statement or answers the question. 3. Unprotected sides and edges means any________or ________of a stairway where there is no stair rail system or wall________or more in height, and any side or edge of a stairway landing, or ladder platform where there is no wall or guardrail system 39 inches or more in height. a. part, area, 39 inches c. stair rail, top edge, 6 feet b. side, edge, 36 inches d. wood, metal, one foot 4. Employers shall provide and install all stairway and ladder fall protection systems required by this subpart and shall comply with all other pertinent requirement of this subpart ________employees begin the work that necessitates the installation and use of stairways, ladders, and their respective fall protection systems. a. while c. before b. when d. within six months of Complete each statement. 5. Subpart________applies to all stairway and ladders used in construction covered under 29 CFR part 1926. 6. List the standard that states a ladder shall be capable of supporting the following load without failure. Each self-supporting portable ladder shall be at least four times the maximum intended load, except that each extra-heavy-duty type 1A metal or plastic ladder shall sustain at least 3.3 times the maximum intended load. Standard ________

textbooks/workforce/Safety_and_Emergency_Management/Workplace_Safety_for_US_Workers_-_Workbook/11%3A_Topic_Quiz/11.17%3A_Quiz_16-Health_Hazards_in_Construction.txt

The set of real numbers consists of the numbers that we use in everyday life. We will define the set of real numbers more precisely, but first, let’s define some other sets of numbers. Natural Numbers: The counting numbers starting with 1: 1, 2, 3, 4, Whole Numbers: 0 and the counting numbers: 0, 1, 2, 3, 4, Integers: Positive and Negative Whole Numbers (includes 0); The whole numbers and their opposites: , -4, -3, -2, -1, 0, 1, 2, 3, 4, Rational Numbers: A number that can be written as a fraction (integers, terminating decimals and repeating decimals) Irrational Numbers: Numbers that cannot be written as a fraction (non-terminating decimals and non-repeating decimals) Real Numbers: All rational and irrational numbers Some numbers can be classified in many categories. The next diagram displays the relationship between the different sets of numbers. Example: Classify the following numbers 1. 2.718 2. $\sqrt{13}$ 3. $\frac{24}{51}$ 4. 101 5. $0.\overline{3}$ 6. -5 See the video for the solutions. The Real Number Line We order real numbers on a number line based on their distance from 0. Positive numbers lie to the right of zero and Negative numbers lie to the left of zero. Each point on the number line corresponds to a real number. Notice that -2 is represented by a distance of 2 units to the left of zero, the negative determines the side of zero while the 2 represents the distance from zero. Similarly, +2 is represented by a distance of 2 units to the right of zero, the positive indicates we move to the right of zero while the 2 represents the distance from zero. When writing positive numbers, it is customary not to write the “+” sign in the front. Example: Plot the following numbers on a real number line 1. 2.718 2. $\sqrt{13}$ 3. $\frac{24}{51}$ 4. 101 5. $0.\overline{3}$ 6. -5 See the video for a demonstration. We determine the size of a number relative to another number using less than ((\<\)) or greater than ($>$) signs. Whichever number is further to the right, is larger, while a number that is further to the left is smaller. We say “$a$ is less than $b$” if $a$ lies to the left of $b$ on a real number line and we write this as: $a < b$. We say “$a$ is greater than $b$” if $a$ lies to the right of $b$ on a real number line and we write this as: $a >b$. Examples: Use $<$ or $>$ to indicate the relationship between the stated numbers 1. 7 ____ -3 2. 5 ____ 12 3. 5.8 ____ 5.7 4. -3.2 ____ -3.1 5. -5 ____ -12 See the video for the solutions. The Opposite of a Number and Absolute Value Definition: The opposite of a real number, $a$, is $-a$. We can think of the opposite of a real number as changing the sign of the real number. Examples: The opposite of 5 is -5. The opposite of -7 is – (-7) = 7 Hence, -(-7) can be read as “the opposite of -7” or “the opposite of the opposite of 7” or 7. Definition: The absolute value of a real number is its distance from zero on a real number line. The notation for the absolute value uses two vertical bars on either side of the number, hence “the absolute value of a” would be denoted as $\left|a\right|$. Since the absolute value represents a distance, its value is always positive. Examples: $\left|5\right|$= 5 since 5 is a distance of 5 from 0 $\left|-7\right|$=7 since -7 is a distance of 7 from 0

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/01%3A_Numbers_Decimals_and_Fractions/1.01%3A_The_Set_of_Real_Numbers.txt

The Addition of Integers and Decimals Adding Numbers with the same signs • Add the absolute values of the numbers and assign the common sign to the result • NOTE: When the signs are both positive, add the values Example: $23+18$ The common sign is +, so the answer will be positive, now we add the numbers to obtain $23+18=41$ Example: $-17+(-31)$ The common sign is -, so the answer will be negative, now we add the absolute values of the numbers to obtain: $-17+\left( -31\right) =$ First, calculate the sum of the absolute values: $\left|-17\right|+\left|-31\right|=\ 17+31=48$ Next, assign the result the common sign, so the final answer is: -48. $-17+\left(-31\right)=-48$ Adding Numbers with the Opposite Signs • Take the absolute value of each number • Subtract the smaller number from the larger number • Assign the sign of the result based on the sign of the number with the larger absolute value • NOTE: The sign of the larger absolute value wins. With practice, these steps will start to feel seamless. Example: $21+(-13)$ First, calculate the absolute value of each number: $\left|21\right|=21 \text{ and } \left|-13\right|=13$ Next, subtract the smaller number from the larger number: $21-13=8$ Next, assign the sign of the number whose absolute value was greater, in this case, the sign of 21 is the sign of the final answer (positive), hence $21+\left(-13\right)=8$ Scientific calculator keystrokes: Example: $28+(-54)$ First, calculate the absolute value of each number: $\left|28\right|=28$ and $\left|-54\right|=54$ Next, subtract the smaller number from the larger number: $54-28=26$ Next, assign the sign of the number whose absolute value was greater, in this case, the sign of -54 is the sign of the final answer (negative), hence $28+\left(-54\right)=-26$ Short-cut: Now that we have gone through the formal process for adding integers, let’s get the general idea of the process: • If the signs are the same, combine the numbers and keep the sign • If the signs are different, disregarding the signs, subtract the smaller number from the larger number, then keep the sign of the larger number Example: $13+(-29)$ Since 29 is larger than 13, we subtract 13 from 29 to get 16, and use the sign of 29 which is negative: -16 Example: $-28+(-54)$ Since the signs are the same, the answer will have the same sign (negative), now combine the numbers 28 + 54 = 82, so the final answer is -82 Similarly with decimal numbers: Example: $-2.34+\left(-5.4\right)=$ Since the signs are the same, we add the numbers: 2.34 + 5.4 = 7.74 and keep the common sign (negative) to get – 7.74 Subtraction of Integers and Decimals When subtracting an integer or decimal, we add the opposite of the number following the subtraction. Example: $15-7=$ In this case, we can perform regular subtraction, however, we can also apply the subtraction rule of adding the opposite to obtain: $15+\left(-7\right)=8$ since 15 is larger than 7, we subtract and keep the sign of the larger number which is positive Example: $3-12=$ Remembering to add the opposite of 12, we get $3+\left(-12\right)=-9$ Since the signs are different and 12 is larger than 3, we subtract $12 -3$ to get 9, but use the sign of 12 which is negative to obtain -9 Likewise with decimal values: Example: $8.23-(-1.2)=$ We first add the opposite of -1.2: $8.23+1.2=$ Next, we combine the numbers since they have same signs to obtain: $8.23-\left(-1.2\right)=8.23+1.2=9.43$ Multiplication and Division of Integers and Decimals To multiply or divide integers and decimals, we use multiply the numbers and use the following rules for the sign: • If two numbers have the same signs, the result is positive • If two numbers have different (opposite) signs, the result is negative Examples: 1. $\left(3\right)\left(-7\right)=\ -21$ 2. $\left(-15\right)\left(-10\right)=150$ 3. $\left(-5.2\right)\left(2\right)=-10.4$ 4. $\left(2\right)\left(7\right)=14$ 5. $\left(-25\right)\div \left(-5\right)=5$ 6. $\left(-12.8\right)\div \left(4\right)=-3.2$ 7. $\left(250\right)\div \left(-10\right)=-25$ 8. $\left(48\right)\div \left(6\right)=8$ Addition, Subtraction, Multiplication, and Division of Integers and Decimals using a Scientific Calculator There are many types of scientific calculators available in the retail market, on our personal computers, and even on our personal devices such as cell phones and tablets. As a result, let’s first distinguish between two types of scientific calculators: A Display calculator and a non-display calculator. Some examples of display calculators are: TI30XIIS, TI-36X Pro, TI-30XS Multiview, and the Casio fx-350ES PLUS. Some examples of non-display calculators are TI-30Xa, most cell phone calculators, and most calculators on personal computers. For our purposes, we will determine if a calculator is a “Display” calculator or a “non-display” calculator by doing the following: Type 2 + 3 on your calculator. • If your screen displays the entire expression 2 + 3, then you have a “Display” calculator. • If you screen displays only the 3 after typing 2 + 3, then you have a “non-display” calculator. On Display calculators, we can usually enter the problem as it is written. On a non-display calculator, we usually must enter the problem in reverse order of operations (see Unit 2 for more information). Let’s revisit some of our earlier examples and calculate them on the scientific calculator. For negative numbers, be sure to use the negative symbol, (-), which is generally at the bottom of the keyboard on a TI calculator and not the subtraction symbol, -, which is usually on the right side of the keyboard. Each calculator is different, so you may have to experiment with your calculator to determine the process. To compute -17+(-31) use the following sequence of keystrokes to obtain -48: Display Calculator: Non-display Calculator: (-) 17 + (-) 31 ENTER 17 (-) + 31 (-)= Type the negative sign before the number Type the negative number after the sign To compute 8.23-(-1.2)= use the following sequence of keystrokes to obtain 9.43: Display Calculator Non-display Calculator: 8.23 - (-) 1.2 ENTER 8.23 - 1.2 (-) = Use the subtraction key, then type the negative sign before the number Use the subtraction key then type the negative sign after the number To compute (-15)(-10) = use the following sequence of keystrokes to obtain 150: Display Calculator Non-display Calculator: (-)15 X (-)10 ENTER 15 (-) X 10 (-) = Type the negative sign before the number Type the negative sign after the number To compute (250)$\div$(-10) = use the following sequence of keystrokes to obtain -25: Display Calculator Non-display Calculator: 250$\div$(-)10 ENTER 250$\div$10(-) = Type the negative sign before the number Type the negative sign after the number Fractions Fractions are real numbers that indicate a portion of a whole. A fraction consists of a numerator and denominator. The denominator represents the number of equal parts of an object and the numerator represents a portion of those equal parts. For example, if pipe is separated into 4 equal parts, ¼ would represent 1 out of 4 of the parts, 2/4 would represent 2 out of the 4 parts, ¾ would represent 3 out of the 4 parts, and 4/4 = 1 would represent all 4 parts or the whole pipe. Likewise, 0/4 would represent 0 of the 4 parts or nothing, hence 0/4 = 0. The rectangle below is divided into two equal parts. Hence 1 of the pieces out of the 2 pieces would represent 1/2. The circle shown below is divided into 8 equal parts. 1 part would represent 1/8. 2 parts would represent 2/8 which would reduce to ¼ for a couple of reasons: 1. if we were to shade 2 of the 8 pieces, that would also represent 1 of 4 equal pieces and 2. 2/8 can be reduced by dividing both the numerator (2) and the denominator (8) by the same number, which in this case would be 2, hence: $\frac{2}{8}=\frac{2\div 2}{8\div 2}=\frac{1}{4}$ The “bar” in a fraction also represents division, so ¼ would also mean $1\div 4$. This can be interpreted as a whole divided into 4 equal parts or 1 of 4 equal parts. Fractions have many applications. Fractions can also be used to represent units such as miles per hour or $\frac{miles}{hour}$. Fractions can also be used to denote ratios and proportions; we will see the use of fractions in these applications in a later unit. Multiplying and Dividing Fractions To multiply fractions: Multiply the numerators and multiply the denominators. To simplify, reduce by dividing like factors (numbers that divide into other numbers). Examples: 1. $\frac{2}{3}\cdot \frac{5}{7}$ a. Multiply the numerators and multiply the denominators. $\frac{2}{3}\cdot \frac{5}{7}=\frac{10}{21}\nonumber$ Since 10 and 21 do not have any common factors, this is the simplified or reduced answer. 2. $\frac{22}{63}\cdot \frac{9}{24}$ a. Multiply the numerators and multiply the denominators. $\frac{22}{63}\cdot \frac{9}{24}=\frac{108}{1512}\nonumber$ b. Simplify by reducing the fraction (divide the numerator and denominator by the same number(s)) $\frac{108}{1512}=\frac{108\div 12}{1512\div 12}=\frac{9}{126}=\frac{9\div 9}{126\div 9}=\frac{1}{14}\nonumber$ Another option for this problem is to reduce before multiplying: $\frac{12}{63}\cdot \frac{9}{24}\nonumber$ a. Reduce the numerators and denominators by dividing each by the same number $\frac{12\div 12}{63\div 9}\cdot \frac{9\div 9}{24\div 12}=\frac{1}{7}\cdot \frac{1}{2}\nonumber$ b. Multiply the numerators and denominators (multiply straight across) $\frac{1}{7}\cdot \frac{1}{2}=\frac{1}{14}\nonumber$ 3. $\frac{24}{72}\cdot \frac{18}{30}$ Since the numbers in the fractions are large, let’s reduce first, then multiply. Determine numbers that divide into both the numerator and denominator: 9 divides into 18 and 72; 6 divides into 24 and 30 OR 6 divides into 18 and 30; 24 divides into 24 and 72 $\frac{24}{72}\cdot \frac{18}{31}=\frac{24\div 6}{72\div 9}\cdot \frac{18\div 9}{30\div 6}=\frac{4}{8}\cdot \frac{2}{5}=\frac{4\div 4}{8\div 4}\cdot \frac{2}{5}=\frac{1}{2}\cdot \frac{2}{5}=\frac{1}{2\div 2}\cdot \frac{2\div 2}{5}=\frac{1}{5} \nonumber$ OR $\frac{24}{72}\cdot \frac{18}{31}=\frac{24\div 24}{72\div 24}\cdot \frac{18\div 6}{30\div 6}=\frac{1}{3}\cdot \frac{3}{5}=\frac{1}{3\div 3}\cdot \frac{3\div 3}{5}=\frac{1}{5} \nonumber$ To divide fractions: Invert the second fraction and change the operation to multiplication and continue as described above. Example: $\frac{3}{5}\div \frac{9}{10}$ $\frac{3}{5}\div \frac{9}{10}= \frac{3}{5}\cdot \frac{10}{9}=\frac{30}{45}=\frac{2}{3}\nonumber$ Example: $\frac{15}{7}\div \frac{25}{21}$ $\frac{15}{7}\div \frac{25}{21}=\frac{15}{7}\cdot \frac{21}{25}=\frac{3}{1}\cdot \frac{3}{5}=\frac{9}{5}\nonumber$ Adding and Subtracting Fractions With like denominators To add or subtract fractions, the fractions must have the same denominator: Step 1: Verify that the fractions are like fractions (fractions with the same denominator). Step 2: Add or subtract the numerators and keep the same denominator. Examples: 1. $\frac{2}{7}+\frac{3}{7}=\frac{2+3}{7}=\frac{5}{7}$ 2. $\frac{14}{17}-\frac{5}{17}=\frac{14-5}{17}=\frac{9}{17}$ With unlike Denominators Step 1: Rewrite the unlike fractions (fractions with different denominators) as like fractions (fractions with the same denominator) with the least common multiple as their new denominator. This new denominator is called the least common denominator (LCD). To determine the least common denominator (LCD), find the smallest common multiple of the denominators, in other words, find the smallest number that both denominators divide into Rewrite the unlike fractions as like fractions by multiplying the numerator and denominator of each fraction by the number that makes the denominator of each the least common denominator. Step 2: Add or subtract the numerators and keep the common denominator. Examples: 1. $\frac{2}{3}+\frac{1}{9}=$ First find the smallest number that both 3 and 9 will divide into, in this case it will be 9, so 9 is the LCD. So, we need to multiply the first fraction by 3/3 to create a 9 in the denominator: $\frac{3}{3}\cdot \frac{2}{3}+\frac{1}{9}=\frac{6}{9}+\frac{1}{9}=\frac{7}{9}\nonumber$ 2. $\frac{3}{7}+\frac{1}{4}=$ The least common denominator = 28 (since 28 is the smallest number that can be divided by both 7 and 4) Next, multiply the numerator and denominator of 3/7 by 4/4 to create a denominator of 28 and multiply the numerator and denominator of ¼ by 7/7 to create a denominator of 28, finally add the numerators and keep the common denominator. $\frac{4}{4}\cdot \frac{3}{7}+\frac{1}{4}\cdot \frac{7}{7}=\frac{12}{28}+\frac{7}{28}=\frac{19}{28}\nonumber$ NOTE: We add, subtract, multiply, and divide negative fractions similar to how we added, subtracted, multiplied and divided negative numbers in Section ___. Percents A percent is defined to be an amount based on 100. If we divide the word into two words, we have “per” and “cent”. Per means divide by and cent means 100, hence divide by 100 or out of 100. Example: 54% means 54 out of 100 We will use percentages to calculate values in Unit ____. Converting between different types of numbers (fractions, decimals, and percentages) To convert from a fraction to a decimal, divide the numerator by the denominator. To convert from a decimal to a fraction, determine the place of the last digit after the decimal, write the fraction as all the digits after the decimal over the last place of the decimal. Example: 0.547 represents 547 thousandths since the last digit after the decimal is in the thousandths place, we have 547/1000. To convert from a fraction to a percent Option 1: Convert the fraction to a decimal, then convert the decimal to a percent Option 2: Use a proportion to write the fraction with a denominator of 100, then using the definition of a percent, the percent will be based on the numerator of the fraction with a denominator of 100. We will explore this option more in Unit ___ when we learn about proportions. To convert from a decimal to a percent, multiply the decimal by 100 or move the decimal place two units to the right. To convert from a percent to a decimal, divide the percent number by 100 or move the decimal place two units to the left.

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/01%3A_Numbers_Decimals_and_Fractions/1.02%3A_Mathematical_Operations.txt

• 2.1: Powers and Roots We can use the following operations on real numbers: addition, subtraction, multiplication, division, and absolute value. In addition to these operations, we can also apply powers and roots. Powers are as the notation for multiplying a number by itself multiple times. Another name for a power is an exponent. • 2.2: Order of Operations The order of operations represents a mathematical agreement of the order in which calculations should be performed. • 2.3: Evaluating Expressions In the Water Industry, we use many formulas to make calculations. As a result, we need to know how to evaluate expressions, that is, substitute known values for variables, and simplify the expression using the order of operations. 02: Powers Roots Order of Operations and Evaluating Expressions As we learned in Unit 1, we can use the following operations on real numbers: addition, subtraction, multiplication, division, and absolute value. In addition to these operations, we can also apply powers and roots. Powers Powers are as the notation for multiplying a number by itself multiple times. Another name for a power is an exponent. The power or exponent is denoted as a superscript. $a^n=\underbrace{(a\cdot a\cdot a\cdot \cdots \cdot a)}_{n\ times}$ In this notation, the a is called the “base” and the $n$ is called the power (or exponent). Examples: 1. $5^3=5\cdot 5\cdot 5=125$ 2. ${(-2)}^4=(-2)(-2)(-2)(-2)=16$ 3. ${(2.3)}^2=(2.3)(2.3)=5.29$ 4. ${(2/3)}^5=2/3\cdot 2/3\cdot 2/3\cdot 2/3\cdot 2/3=32/243$ Roots Roots are obtained by “undoing” a power. There are many types of roots, we will look at square roots, cube roots, and fourth roots. • The square root of a number, $a$, is $b$ if$\ b^2=a$ • The cube root of a number, $a$, is $b$ if $b^3=a$ • The fourth root of a number, $a$, is $b$ if $b^4=a$ • We can generalize this to say the n${}^{th}$ root of a number, a, is b if $b^n=a$ We use a radical symbol to represent the operation of a root: $\sqrt{\quad }$ • Square root symbol: $\sqrt{\quad }$ • Cube root symbol: $\sqrt[3]{\quad}$ • Fourth root symbol: $\sqrt[4]{\quad}$ • n${}^{th}$ root symbol: $\sqrt[n]{\quad}$ The number under a radical symbol is called the radicand. Examples: 1. The square root of 9 is denoted as $\sqrt{9}$, since $3\wedge 2=9,\ then\ \sqrt{9}=3$. 2. $\sqrt{49}$, since $7^2=49,\ then\ \sqrt{49}=7$. 3. The cube root of 8 is denoted as $\sqrt{}$, since $2^3=8,\ then\ \sqrt{8}=2$. 4. $\sqrt{1.44}=1.2$ since ${\left(1.2\right)}^2=1.44$ 5. $\sqrt{\frac{36}{121}}=6/11$ since${\left(\frac{6}{11}\right)}^2=36/121$ To compute a root: • On a scientific display calculator, type the radical symbol first, then the radicand followed by enter. Example: $\sqrt{1.44}$ the keystrokes would be $\sqrt{\quad }\ 1.44\, Enter$ • On a non-display calculator, type the radicand first, then the radical symbol (do not press =) Example: $\sqrt{1.44}$ the keystrokes would be $1.44\, \sqrt{\quad }$ 2.02: Order of Operations The order of operations represents a mathematical agreement of the order in which calculations should be performed. The order is Grouping Symbols, Exponents, Multiplication and Division as they appear left to right, and Addition and Subtraction as they appear left to right. Traditionally, we use PEMDAS as the acronym to remember the order of operations using Parentheses, Exponents, Multiplication, Division, Addition, and Subtraction. To allow us to perform operations on more problems, let’s consider Grouping Symbols as the first order since it would encompass parentheses, brackets, roots, absolute values, and fraction bars. So, let’s learn the acronym GEMDAS, one way to remember the letters is to remember GEMDAS: Greater Education Makes Doctors and Scholars or Good (Environment) Efforts Minimizes Diseased Animals Swimming Grouping Symbols-Exponents-Multiplication/Division-Addition/Subtraction GEMDAS Example $1$ Simplify $5-3(4-6\div (-2))$. Solution In this problem, we start with the inner most grouping symbol which would be the parentheses around the -2, however, there is no operation with this set of parentheses, so we move to the other set of parentheses: $(4-6\div (-2))$. Within this set of parentheses, the division must occur before the subtraction, so we computer $6\div (-2)=-3$, so the parentheses would be $(4-(-3))\nonumber$ Next, we can recall that we subtract integers by adding the opposite, so $(4-(-3))=4+3=7$ continuing, we now have $5-3(4-6\div (-2))=5-3(7)\nonumber$ Next, we perform the multiplication before the subtraction to obtain: $5-21=-15\nonumber$ Example $2$ Simplify $2+3\cdot \sqrt{21-5}-8+4^2$. Solution In this problem, we start with the radical since it is a grouping symbol: $\sqrt{21-5}=\sqrt{16}=4\nonumber$ So now we have: $2+3\cdot 4-8+4^2\nonumber$ Next, we apply the power or exponent: $4^2=16\nonumber$ So, we now have: $2+3\cdot 4-8+16\nonumber$ Next, we perform multiplication: $3\cdot 4=12 \nonumber$ So, we now have: $2+12-8+16\nonumber$ Finally, we perform addition and subtraction as it appears left to right to obtain: $2+12-8+16=14-8+16=6+16=22\nonumber$ 2.03: Evaluating Expressions In the Water Industry, we use many formulas to make calculations. As a result, we need to know how to evaluate expressions, that is, substitute known values for variables, and simplify the expression using the order of operations. Example $1$ If $x=4$ and $y=3$ evaluate $3xy^2+2\sqrt{x}$. Solution First, substitute the given values for $x$ and $y$: $3(4)(3)^2 + 2 \sqrt{4} \nonumber$ Next, perform order of operations to simplify: $3\left(4\right){\left(3\right)}^2+2\sqrt{4}=3\left(4\right)\left(9\right)+2\left(2\right)=108+4=112 \nonumber$ Example $2$ If $a=9\ and\ b=7$, evaluate $\frac{2\sqrt{a}+3}{b-5}$. Solution First, substitute the given values for a and b: $\frac{2\sqrt{9}+3}{7-5}$ Next, simplify using order of operations: $\frac{2\cdot 3+3}{7-5}=\frac{6+3}{7-5}=\frac{9}{2}$ Recall from Unit 1, we could convert this fraction to a decimal to obtain 4.5, however, the general rule of thumb is to use decimals only when you start with decimals, or the directions states to use decimals. Example $3$ A water plant has a rectangular basin with a base that is in the shape of a square with sides of length x and the height of the basin is y. As a result, the volume is calculated using the following expression: $x^2y$. If the length of the base of the basin is 50 feet and the height of the basin is 20 feet, calculate the volume of the basin. Solution First, we substitute the values for x and y: $x^2y={\left(50\ feet\right)}^2\cdot \left(20\ feet\right)$ Next, we simplify the expression using order of operations to obtain: $\left(2500\ ft^2\right)\left(20\ ft\right)=50,000\ ft^3$ Example $4$ To estimate the extra water a town needs to store for emergencies, we must multiply the population by 45 gallons, then add 42,000 gallons to account for what the fire fighters would need in case of a fire, and then multiply the result by a safety factor of 1.8. a. Write an expression for calculating the amount of extra water a town needs to store in case of an emergency. b. Use the expression to calculate the amount of extra water a town needs to store in case of an emergency if the population of the town is 48,000. Solution a. We begin by converting the English to math: Multiply the population, let’s call the population P, by 45 gallons: $45P$ Then add 42,000 gallons: $45P+42,000$ Then multiply by 1.8: $1.8(45P+42,000)$ Hence, the amount of extra water needed is $1.8(45P+42,000)$ b. If the population is 48,000, we will replace P in the above expression with 48,000 to obtain: $1.8\left(45\cdot 48,000+42,000\right)=1.8\left(2,160,000+42,000\right)=1.8\left(2,202,000\right)=3,963,600$ Hence, the town needs to reserve 3,963,600 gallons of water in case of an emergency.

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/02%3A_Powers_Roots_Order_of_Operations_and_Evaluating_Expressions/2.01%3A_Powers_and_Roots.txt

The addition, subtraction, multiplication, and division properties of equality allow us to add, subtract, multiply, or divide the same value on both sides of an equation, this guarantees the equation remains true (note, we cannot divide by zero). Concept: We know this to be a true statement: $5=5$ The statement will remain true if we perform the same operation on both sides of the equation. • Add 4 on both sides of the equation to obtain:\begin{align*} 5+4 &=5+4 \[4pt] 9 &=9 \end{align*} • Subtract 10 on both sides of the original equation to obtain: \begin{align*} 5-10&=5-10 \ -5&=-5 \end{align*} • Multiply by 2 on both sides of the original equation to obtain: \begin{align*} 5\cdot 2&=5\cdot 2 \ 10&= 10 \end{align*} • Divide by 15 on both sides of the original equation to obtain: \begin{align*} \frac{5}{15}&= \frac{5}{15}\ \frac{1}{3}&=\frac{1}{3} \end{align*} We use the Addition, Subtraction, Multiplication, and Division Properties of Equality to solve equations for a specified variable or unknown. Process for Solving a Basic Linear Equation in One-Variable • Isolate the variable by “undoing” the operation on the variable, that is, applying the opposite operation on both sides of the equation using the Properties of Equality Example $1$ Solve for x: $x+2=9$ Solution Since 2 is being added to x, to isolate the x, we need to “undo” the addition of 2, the opposite of adding 2 is subtracting 2, so using the Subtraction Property of Equality, let’s subtract 2 on both sides of the equation to obtain: $x+2-2=9-2$ $x=7$ Example $2$ Solve for x: $x-7=13$ Solution Since 7 is being subtracted from x, to isolate the x, we need to “undo” the subtraction of 7, the opposite of subtracting 7 is adding 7, so using the Addition Property of Equality, let’s add 7 on both sides of the equation to obtain: $x-7+7=13+7$ $x=20$ Example $3$ Solve for x: $3x=12$ Solution Since x is being multiplied by 3, to isolate the x, we need to “undo” the multiplication by 3, the opposite of multiplying by 3 is dividing by 3, so using the Division Property of Equality, let’s divide by 3 on both sides of the equation to obtain: $\frac{3x}{3}=\frac{12}{3}$ $x=\frac{12}{3}=4$ Example $4$ Solve for x: $\frac{x}{8}=2$ Solution Since x is being divided by 8, to isolate the x, we need to “undo” the division by 8. The opposite of dividing by 8 is multiplying by 8, so using the Multiplication Property of Equality, let’s multiply by 8 on both sides of the equation to obtain: $\frac{x}{8}\cdot 8=2\cdot 8$ $\frac{x}{8}\cdot \frac{8}{1}=2\cdot 8$ $x=16$ Example $5$ Solve for x: $\frac{1}{2}x=5$ Solution We can approach this problem in a couple of different ways, Option 1: Read the problem as x is being multiplied by ½, hence we can divide both sides by ½ to isolate the variable, x. $\frac{\frac{1}{2}x}{\left(\frac{1}{2}\right)}=\frac{5}{\left(\frac{1}{2}\right)}$ $x=\frac{5}{\left(\frac{1}{2}\right)}=\frac{5}{1}\cdot \frac{2}{1}=\frac{10}{1}=10$ Option 2: Rewrite the problem or think of the problem as being read as x is being divided by 2 since ½ $x$ is equivalent to $\frac{x}{2}$, so we can multiply both sides of the equation by 2 to isolate $x$: $\frac{1}{2}x=5$ $\frac{x}{2}=5$ $\frac{x}{2}\cdot 2=5\cdot 2$ $x=10$ Similarly, if we have a fraction times a variable, let’s say x, then we can multiply both sides of the equation by the reciprocal of the fraction (flip the fraction such that the numerator becomes the denominator, and the denominator becomes the numerator): Example $6$ Solve for x: $\frac{2}{3}x=7$ Solution $\frac{2}{3}x=7$ $\boldsymbol{\frac{3}{2}}\cdot \frac{2}{3}x=\boldsymbol{\frac{3}{2}}\cdot 7$ $x=\frac{3}{2}\cdot \frac{7}{1}=\frac{21}{2}$ Process for solving a linear equation in one variable with multiple operations When solving a linear equation with multiple operations, we reverse the order of operations because we are “undoing” the original operations. Example: 1. Solve for x: $2x+5=15$ Order of operations state to perform multiplication, then addition, so when solving, we will reverse this order so we will “undo” the addition first, then we will “undo” the multiplication $2x+5=15\nonumber$ Step 1: “Undo the addition by 5” by subtracting 5 on both sides of the equation $2x+5-\boldsymbol{5}=15-\boldsymbol{5} \nonumber$ $2x=10\nonumber$ Step 2: “Undo the multiplication by 2” by dividing by 2 on both sides of the equation $\frac{2x}{\boldsymbol{2}}=\frac{10}{\boldsymbol{2}}\nonumber$ $x=5 \nonumber$ We can check our answer by substituting the value for x into the original equation and verifying that the equation is true: $2\left(5\right)+5=10+5=15 \,$ 2. Solve for x: $\frac{2}{3}x+\frac{1}{5}=\frac{2}{7}$ $\frac{2}{3}x+\frac{1}{5}=\frac{2}{7}\nonumber$ Step 1: Subtract $\frac{1}{5}$ on both sides of the equation $\frac{2}{3}x+\frac{1}{5}-\boldsymbol{\frac{1}{5}}=\frac{2}{7}-\boldsymbol{\frac{1}{5}}\nonumber$ $\frac{2}{3}x=\frac{2}{7}-\frac{1}{5} \nonumber$ Step 2: Find an LCD to subtract the fractions on the right side: $\frac{2}{3}x=\frac{2}{7}\cdot \frac{5}{5}-\frac{1}{5}\cdot \frac{7}{7}\nonumber$ $\frac{2}{3}x=\frac{10}{35}-\frac{7}{35} \nonumber$ $\frac{2}{3}x=\frac{3}{35}\nonumber$ Step 3: Multiply both sides of the equation by the reciprocal of $\frac{2}{3}$ which would be $\frac{3}{2}$ : $\boldsymbol{\frac{3}{2}}\cdot \frac{2}{3}x=\boldsymbol{\frac{3}{2}}\cdot \frac{3}{35}\nonumber$ $x=\frac{9}{70}\nonumber$ Process for solving linear equations with parenthesis When an equation contains parentheses, we can clear the parentheses using the distributive property. Distributive Property: $a\left(b+c\right)=ab+ac$ Examples 1. Solve for m: $5\left(m+3\right)-2\left(7-m\right)=12$ Step 1: Apply the distributive property to clear the parentheses: $5m+5\left(3\right)-2\left(7\right)-2(-m)=12 \nonumber$ $5m+15-14+2m=12 \nonumber$ Step 2: Combine like terms $5m+2m+15-14+1=12\nonumber$ $7m+1=12 \nonumber$ Step 3: Isolate the variable by subtracting 1 on both sides, then dividing both sides by 7 $7m+1-\boldsymbol{1}=12-\boldsymbol{1}\nonumber$ $7m=11\nonumber$ $\frac{7m}{\boldsymbol{7}}=\frac{11}{\boldsymbol{7}}\nonumber$ $m=\frac{11}{7}\nonumber$ 2. Solve for x: $-7\left(3-x\right)+11=2\left(x-3\right)$ Step 1: Clear the parentheses by using the distributive property $-21+7x+11=2x-6 \nonumber$ Step 2: Combine like terms $-10+7x=2x-6 \nonumber$ Step 3: Isolate the variable by subtracting $2x$ on both sides of the equation and adding 10 on both sides of the equation $-10+\boldsymbol{10}+7x-\boldsymbol{2x}=2x-\boldsymbol{2x}-6+\boldsymbol{10}\nonumber$ $5x=4\nonumber$ Now, divide both sides by 5: $\frac{5x}{\boldsymbol{5}}=\frac{4}{\boldsymbol{5}}\nonumber$ $x=\frac{4}{5}\nonumber$ 3.02: Solving a Formula for a Variable (Rewriting a Formula) In the Water Industry, we use lots of formulas for computing area, volume, pressure, cost, and so much more. Sometimes, we need to rewrite a formula in terms of a different quantity. When solving a formula for a particular variable, it is sometimes helpful to place a rectangle or a circle around the variable you are isolating since formulas contain many variables and we may lose our focus as to which variable we are isolating. We will proceed as we did for solving linear equations by “undoing” operations to isolate the variable. Example $1$ The volume of a rectangular tank is given by $V=LWH$, rewrite the formula by solving for $H$. Solution To “undo” the multiplication of H by LW, we divide both sides of the equation by LW to obtain: $\frac{V}{ \boldsymbol{LW}}=\frac{LWH}{ \boldsymbol{ LW}}$ ${V}\over {LW}=H$ Example $2$ The filtration rate is defined as Filtration Rate $=\frac{Flow}{Surface \, \, Area}$. Solve this equation for the Surface Area. Solution Step 1: Multiply both sides of the equation by Surface Area (to remove the Surface Area from the denominator. In other words, we cannot isolate Surface Area until it is no longer in the denominator) $\left(Filtration\,\, Rate\right)\cdot \left(\boldsymbol{Surface\,\, Area}\right) =\frac{Flow}{Surface\,\, Area}\cdot \left(\boldsymbol{Surface\,\, Area}\right)$ $\left(Filtration\,\, Rate\right) \cdot \left(Surface\,\, Area\right) =Flow$ Step 2: Isolate the Surface Area by dividing both sides by Filtration Rate $\frac{\left( Filtration\,\, Rate\right)\cdot \left(Surface\,\, Area\right) }{(\boldsymbol{Filtration\,\, Rate})}=\frac{Flow}{(\boldsymbol{Filtration\,\, Rate})}$ $Surface\,\, Area=\frac{Flow}{Filtration\,\, Rate}$ This is helpful if we need to calculate the Surface Area and we are given the flow and the filtration rate. 3.03: Solving Quadratic Equations of the Form- (x-a)c When solving equations of the form: ${\left(x-a\right)}^2=c$, we can use the square root property which states to drop the square and take the positive and negative square root of the constant, c. Mathematically, we say the following: If ${\left(x-a\right)}^2=c$, then $x-a=\pm \sqrt{c}$ next, add a on both sides of the equation to obtain $x=a\pm \sqrt{c}$ Example $1$ Solve ${\left(x-5\right)}^2=16$ Solution To solve, we first drop the square from the left side and take the positive and negative square root of 16 to obtain $x-5=\pm \sqrt{16}$ Next, we simplify the square root $x-5=\pm 4$ Next, we isolate the variable, x by adding 5 on both sides of the equation: $x-5+\boldsymbol{5}=+\boldsymbol{5}\pm 4$ Such that after simplifying, we obtain two answers $x=5\pm 4$ $x=5+4 \,\,\text{ and }\,\, x=5-4$ $x=9\,\, \text{ and }\,\, x=1$ Example $1$ Solve $3{\left(x+2\right)}^2+5=80$ Solution To solve, we must first isolate the perfect square to create the form: ${\left(x-a\right)}^2=c$, so we first subtract 5 on both sides of the equation, then divide both sides by 3 $3{\left(x+2\right)}^2+5-\boldsymbol{5}=80-\boldsymbol{5}$ $3{\left(x+2\right)}^2=75$ $\frac{3\left(x+2\right)^2}{\boldsymbol{3}}=\frac{75}{\boldsymbol{3}}$ ${\left(x+2\right)}^2=25$ Next, we drop the square and take the positive and negative square root of 25 to obtain $x+2=\pm \sqrt{25}$ $x+2=\pm 5$ Next, we isolate the x by subtracting 2 on both sides of the equation $x+2-\boldsymbol{2}=-\boldsymbol{2}\pm 5$ After simplifying, we obtain two answers $x=-2\pm 5$ $x=-2+5 \,\,\text{ and }\,\, x=-2-5$ $x=3 \,\,\text{ and }\,\, x=-7$

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/03%3A_Solving_Equations_and_Formulas/3.01%3A_Addition_Subtraction_Multiplication_and_Division_Properties_of_Equality.txt

• 4.1: Scientific Notation Scientific notation is used to make very large numbers such as 4,895,000,000 or very small numbers such as 0.0000073 easier to use. In the Water industry, we use very large numbers when referring to the volume of water in large tanks or very small numbers when referring to pollutants per gallon of water. • 4.2: Rounding We have been using decimal numbers throughout our lives, but let’s take some time to formalize the language so we can learn how to round decimals appropriately. • 4.3: Dimensional Analysis Often in the Water and Wastewater Operations, we must use the relationship between different quantities to determine the results of various calculations. In other words, we will need to perform calculations while also recognizing the changes in the measurements and dimensions to assure the measurement of the result is reasonable. Thumbnail: Expansion of small numbers expressed in scientific notation (CC BY SA 3.0 Unported; Brian Brondel via Wikipedia) 04: Scientific Notation Rounding Conversions and Dimensional Analysis Scientific notation is used to make very large numbers such as 4,895,000,000 or very small numbers such as 0.0000073 easier to use. In the Water industry, we use very large numbers when referring to the volume of water in large tanks or very small numbers when referring to pollutants per gallon of water. Scientific Notation Form: $\underbrace{(a\ decimal)}_{between\ 0\ and\ 10\ \left(not\ including\ 10\right)} \times {10}^{power}$ To convert from scientific notation to the actual number • For a positive exponent on the 10, move the decimal place to the right the equivalent number of spaces as the power • For a negative exponent on the 10, move the decimal place to the left the equivalent number of spaces as the absolute value of the power Example $1$ Convert the scientific notation to the actual number: $8.735 \times {10}^7$ Solution Since the power of 10 is positive 7, we will move the decimal place 7 units to the RIGHT to obtain: 87,350,000 Example $2$ Convert the scientific notation to the actual number: $2.356 \times {10}^{-4}$ Solution Since the power of 10 is negative 4, we will move the decimal place 4 units to the LEFT to obtain: 0.2356 To convert a positive number to scientific notation • Move the decimal place to the right of the first non-zero digit. This will be the decimal number portion of the scientific notation. • If the decimal place was moved to the left, use a positive power of 10 based on the number of places the decimal was moved • If the decimal place was moved to the right, use a negative power of 10 based on the number of places the decimal was moved Example $3$ Convert 567,900,000 to scientific notation. Solution Currently, the decimal is understood to be after the last digit since this is a whole number, so move the decimal to the left 8 places so the decimal is between 5 and 6, hence the scientific notation is $5.679 \times {10}^8$ Example $4$ Convert 0.00032 to scientific notation. Solution Move the decimal to the right 4 places so the decimal is between 3 and 2 to create a decimal number of 3.2 and the power of 10 would then be negative 4 since we moved the decimal to the right 4 places. The scientific notation would be $3.2 \times {10}^{-4}$ Note Numbers that are larger than 1 will have a positive power of 10 in scientific notation and numbers that are less than 1 (but still positive) will have a negative power of 10 in scientific notation. Display of scientific notation on scientific calculators To multiply and divide numbers in scientific notation, we can multiply (or divide) the decimals and multiply (or divide) the powers of 10, then simplify by rewriting into the proper scientific notation form. To do this, we will need to understand some rules of exponents. Rule of Exponents 1. When multiplying expressions with the same base, we keep the base and add the exponents: $a^x\cdot a^y=a^{x+y}$ 2. When dividing expressions with the same base, we keep the base and subtract the exponents: $\frac{a^x}{a^y}=a^{x-y}$ 3. Negative exponents become positive exponents if we move the expression to the opposite side of a fraction: $a^{-x}=\frac{1}{a^x} \,\,\, \text{and} \,\,\, \frac{1}{a^{-x}}=a^x$ 4. A non-zero expression raised to an exponent of zero is equivalent to 1: $a^0=1$ Example $5$ Multiply and simplify using scientific notation: $(2.45\times {10}^6)(3.23\times {10}^{-15})$ Solution First, we can rearrange the multiplication to obtain: $\left(2.45\times {10}^6\right)\left(3.23\times {10}^{-15}\right)$ $=\left(2.45\right)\left(3.23\right)\times ({10}^6)({10}^{-15})$ Next, we can multiply the decimals, then multiply the powers of 10 using an exponent rule: $=7.9135\times {10}^{6+\left(-15\right)}$ $=7.9135\times {10}^{-9}$ Since the decimal value of 7.9135 is between 0 and 10 (not including 10), then this is the proper scientific notation form. Example $2$ Multiply and simplify using scientific notation: $(8.7\times {10}^{-6})(2.5\times {10}^{12})$ Solution First, we can rearrange the multiplication to obtain: $(8.7\times {10}^{-6})(2.5\times {10}^{12})=\left(8.7\right)\left(2.5\right)\times ({10}^{-6})({10}^{12})$ Next, we can multiply the decimals, then multiply the powers of 10 using an exponent rule: $=21.75\times {10}^{-6+12}$ $=21.75\times {10}^6$ Since the decimal value of 21.75 is not between 0 and 10 (not including 10), we need to convert it to proper scientific notation form and simplify further $21.75\times {10}^6=\left(2.175\times {10}^1\right)\times {10}^6$ $\ \ \ \ \ \ =2.175\times {10}^{1+6}$ $=2.175\times {10}^7$ Example $3$ Divide and simplify using scientific notation: $\frac{4.125\times {10}^{13}}{7.5\times {10}^{-2}}$ Solution First, we divide the decimals, then divide the powers of 10 using an exponent rule: $\frac{4.125\times 10^{13}}{7.5\times 10^{-2}}=\frac{4.125}{7.5} \times \frac{10^{13}}{10^{-2}}$ $=0.55\times {10}^{13-\left(-2\right)}$ $=0.55\times {10}^{15}$ Since the decimal value of 0.55 is not between 0 and 10 (not including 10), we need to convert it to proper scientific notation form and simplify further $0.55\times {10}^{15}=\left(5.5\times {10}^{-1}\right)\times {10}^{15}$ $=5.5\times {10}^{-1+15}$ $=5.5\times {10}^{14}$

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/04%3A_Scientific_Notation_Rounding_Conversions_and_Dimensional_Analysis/4.01%3A_Scientific_Notation.txt

We have been using decimal numbers throughout our lives, but let’s take some time to formalize the language so we can learn how to round decimals appropriately. Reading decimal numbers: Fraction Decimal Name $\dfrac{1}{10}$ 0.1 One-tenth $\dfrac{1}{100}$ 0.01 One-hundredth $\dfrac{1}{1000}$ 0.001 One-thousandth $\dfrac{1}{10000}$ 0.0001 One-ten-thousandth $\dfrac{1}{100000}$ 0.00001 One-hundred-thousandth The place values to the right of the decimal are given the following names: Tenths, hundredths, thousandths, ten-thousandths, hundred-thousandths, millionths, etc. As a result, we read 5.643 as “five and six-hundredth-forty-three- thousandths since the last digit after the decimal ends in the thousandths place. Examples: 1. 45.6 is read as “forty-five and six tenths” 2. In the number 543.7892, the 8 is in which place value? Since the 8 is two digits after the decimal point, the place value is hundredths. 3. 0.0143 is read as “one-hundred-forty-three ten-thousandths For rounding decimals, to round to the nearest decimal place, 1. Consider the number to the right of the desired rounding place value 1. If the digit is less than 5 (4 or less), we truncate at the desired rounding place value, that is, we drop all the digits after the desired rounding place value 2. If the digit is 5 or more, we round up by adding 1 to the desired rounding place value before dropping all the remaining digits to the right Examples: 1. Round 32.784 to the nearest hundredth.Since 8 is in the hundredths place, we consider the number immediately to the right (in the thousandths place), since 4 is less than 5, we drop all the digits after the hundredths place to obtain 32.78. 2. Round 32.786 to the nearest hundredth.Since 8 is in the hundredths place, we consider the number immediately to the right (in the thousandths place), since 6 is more than 5, we add 1 to 8 (in the hundredths place, this is called rounding up) and we drop all the digits after the hundredths place to obtain 32.79. 3. Round 6.48327 to the nearest thousandth.We start by consider the value of the digit immediately after the thousandths place, which is 2, since 2 is less than 5, we drop all the digits after the thousandths place to obtain 6.483 as the rounded number to the nearest thousandth. 4. Round 6.4592 to the nearest 1. Tenth $\Rightarrow$ Since 5 immediately follows the tenths place, we round the 4 in the tenths place up one number to 5 (by adding 1 to 4) to obtain 6.5 as the rounded number to the tenths place. 2. Hundredth $\Rightarrow$ Since 9 immediately follows the hundredths place, we round the 5 in the hundredths place up to 6 to obtain 6.46 as the rounded number to the hundredths place. 3. Thousandth $\Rightarrow$ Since 2 immediately follows the thousandths place, we round the 5 in the hundredths place up to 6 to obtain 6.46 as the rounded number to the hundredths place. 5. Round 6.4597 to the nearest thousandth (to three decimal places).Since the fourth digit is 5 or higher, we must round the third digit after the decimal up by adding 1, but if we add 1 to 9, we would get 10, so we think of 59 (the second and third places after the decimal and round it up by 1 to obtain 60, hence 6.4597 rounded to three decimal places or the nearest thousandth becomes 6.460. We must write the zero in the thousandth place in this case to show the rounding to three decimal places, without the zero on the end, the rounding would be incorrect. Significant Figures Significant figures are used to assure the accuracy of a calculation based on the numbers used within the calculation. When a problem doesn’t specify how to round an answer or it is not implied in its context (such as money), we use significant figures. The following digits are considered significant: • Digits between 1-9. Example: 875 would consist of three significant figures. • Any zeros between non-zero digits. Example: 20.07 and 5608 would both consist of four significant figures. • The trailing zeros in a decimal number are significant The following digits represent ambiguous cases, so the best method to determine the significant figures is to convert the number to scientific notation: • Any zeros in numbers that do not contain a decimal point. Example: 530,000 depending on the situation, this could represent two significant figures or six significant figures, so let’s convert it to scientific notation to obtain: $5.3\ X\ {10}^4$ which would now represent two significant figures. In general, if the zeros are used to locate the decimal point, they are not significant figures, whereas if the zeros are being used for accuracy, they are included as significant figures. The following digits are not significant: • If a number is less than 1, the zeros that occur after the decimal point but before a non-zero digit. Example: 0.0075 would consist of two significant figures When performing calculations, the number of significant figures of the final answer is equivalent to the fewest number of significant figures provided in the calculation. Examples: 1. State the number of significant figures in each of the following numbers 1. 3.402 $\Rightarrow$ 4 significant figures, the non-zero digits are counted since they are between 1-9 and the zero is counted since it is between two non-zero digits 2. 0.000472 $\Rightarrow$ 3 significant figures; this number is less than 1, so the zeros after the decimal point but before the non-zero digits do not count, so we only count the digits between 1-9 3. $8.0\ X\ {10}^4$ $\Rightarrow$ 2 significant figures; we consider the decimal value (not the power of 10), the trailing zero counts since it is used to show accuracy of the number 4. 452,000 $\Rightarrow$ ambiguous case, 3 to 6 significant figures depending on the context of the number 2. Round the following numbers to three significant figures 1. 89.0146 $\Rightarrow$ Since the zero after the decimal point is significant since it is between two non-zero digits, we round to the nearest tenth in this cased to obtain 89.0 2. 0.005324 $\Rightarrow$ Since this number is less than 1, the zeros immediately to the right of the decimal point are not significant, so to round to three significant figures, we round to the nearest hundred-thousandth to obtain 0.00532 3. 872.58 $\Rightarrow$ Since all the digits are significant, to round to three significant figures, we round to the nearest whole number (three digits from the left) to obtain 873. 4. 8723.158 $\Rightarrow$ Since all the digits are significant, to round to three significant figures, we round to the nearest ten (three digits from the left) to obtain 8720. 5. 65,207 $\Rightarrow$ Since all the digits are significant, to round to three significant figures, we round to the nearest hundred (three digits from the left) or 65,200. 3. Based on the given calculations, state the number of significant figures of the answer, then perform the calculation and round it based on the significant figures 1. $(4.5)(2.33)(6.232)$ $\Rightarrow$ Two significant figures since 4.5 has the least number of significant figures.$\left(4.5\right)\left(2.33\right)\left(6.232\right)=65.34252\,\,\, \text{which rounds to 65} \nonumber$ 2. $\frac{(2.543)(3.516)}{0.01}$ $\Rightarrow$ One significant figure since 0.01 has the least number of significant figures. $\frac{(2.543)(3.516)}{0.01}=\frac{8.941188}{0.01}=894.1188 \,\,\, \text{which rounds to 900}\nonumber$

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/04%3A_Scientific_Notation_Rounding_Conversions_and_Dimensional_Analysis/4.02%3A_Rounding.txt

Often in the Water and Wastewater Operations, we must use the relationship between different quantities to determine the results of various calculations. In other words, we will need to perform calculations while also recognizing the changes in the measurements and dimensions to assure the measurement of the result is reasonable. Conversions In the Water Industry, we often convert between units of measurement such as gallons to liters or days to hours. To convert between units of measurement, we first need to know the conversion factors or equivalencies. These equivalencies are usually provided in a chart and over time, you will most likely start to learn the ones that are used often, much like we know there are 24 hours in a day or 7 days in a week or 12 feet in a yard. When converting between units, the idea is to multiply by a form of 1. We will create a fraction that is equivalent to 1 by doing the following: 1. Set up the starting measurement as a fraction. 2. The unit we are removing is placed opposite the position of where it is currently 3. The “new” unit will be placed in the other position 4. Insert the equivalencies Examples: 1. Convert 153 miles per hour to feet per hour. We start by writing the words into a fraction, namely, $\frac{153\,\, miles}{1\,\, hour}$. Next, since we want to convert miles to feet, we need to eliminate the miles, so we will multiply by a fraction with miles in the denominator (opposite of where the miles are currently) and since we need to replace the miles with feet, we will place the feet in the numerator (to replace the current miles), then insert the equivalencies, 5280 feet = 1 mile, hence we multiply the original measurement by $\frac{5280\,\, feet}{1\,\, mile}$$\frac{153\,\, miles}{1\,\, hour}\cdot \frac{5280\,\, feet}{1\ mile}\nonumber$Next, we simplify by reducing or canceling the mile unit of measurement and multiply straight across to obtain:$\frac{153\,\, \cancel{miles}}{1\,\, hour}\cdot \frac{5280\,\, feet}{1\,\, \cancel{mile}}=\frac{153}{1\,\, hour}\cdot \frac{5280\,\, feet}{1}=\frac{807,840\,\, feet}{1\,\, hour} \text{or 807,840 feet per hour}\nonumber$ 2. The Plant needs to treat every 60 gallons of water with 7 grams of chlorine. However, the chlorine is packaged in ounces. Convert the required amount from gallons/gram to gallons/ounce. We start by writing the given information as a fraction, namely, $\frac{60\,\, gallons}{7\,\, grams}$. Next, since we want to convert the grams to ounces and the grams are currently in the denominator, we create a fraction with the grams in the numerator and the ounces in the denominator (so that the grams are opposite each other) and then insert the equivalencies to obtain:\begin{aligned} \frac{60\,\, gallons}{7\,\, grams}\cdot \frac{1\,\, gram}{0.03527396195\,\, ounces}&\, \ \frac{60\,\, gallons}{7\,\, \cancel{grams}}\cdot \frac{1\,\, \cancel{gram}}{0.03527396195\,\, ounces}&=\frac{60\,\, gallons}{0.246917734\,\, ounces} \ &=\frac{60}{0.246917734}\frac{gal}{oz}=242.9959125 \,\, gal/oz \end{aligned} To convert between metric units, we can use the same process described above or we can use a prefix table and move the decimal point based on the direction and the number of places it takes to move from one metric unit of measure to the others based on the order of the sizes of the prefixes. Let’s begin by using a mnemonic to learn the basic six prefixes along with the base unit measurement and their order on the ladder. “King Henry Died By Drinking Chocolate Milk” This statement can help with remembering the order of six prefixes and the base unit. For the base, you can have any of the following units of measurement: • Meters (length) • Grams (weight) • Liters (volume) • Meters${}^{2}$ (area) To convert from one prefix to another, 1. Determine if we must move left or right 2. Determine the number of places to move on the ladder 3. Move the decimal place in the number the same number of places in the same direction as we moved on the prefix ladder. NOTE: Mega is three units to the left of Kilo and Micro is three units to the right of Milli Examples: 1. Convert 674.325 centimeters to dekameters Using the ladder, to move from centi to deka, we must move LEFT 3 places, hence, we must move the decimal place 3 places to the left to obtain 0.674325 dekameters. 2. Convert 67 hectoliters to milliliters. Using the ladder, to move from hector to milli, we must move RIGHT 5 places, hence, we must move the decimal place 5 places to the right, keeping in mind that for a whole number, the decimal is understood to be after the last digit, 67 hectoliters convert to 6,700,000 milliliters. 3. Convert 6.5 kilograms to megagrams. Since mega is 3 places to the left of kilo, we must move the decimal place 3 places to the left so 6.5 kilograms becomes 0.0065 megagrams. 4. Convert 8765 centimeters to meters. Remembering that the base represents meters, we need to move from centi to the base (meters) which would be LEFT by 2 places, so move the decimal two places to the left to convert 8765 centimeters to 87.65 meters.

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/04%3A_Scientific_Notation_Rounding_Conversions_and_Dimensional_Analysis/4.03%3A_Dimensional_Analysis.txt

A ratio is a comparison of two numerical quantities in the same units that is usually expressed as a fraction. Examples: 1. The ratio of 2 meters to 7 meters is $\frac{2m}{7m}=\frac{2}{7}$. 2. There are 200,000 gallons of water in a rectangular basin and 400,000 gallons of water in a cylindrical basin. 1. What is the ratio of the number of gallons of water in the rectangular basin to the cylindrical basin?$\frac{200,000\,\, gallons}{400,000\,\, gallons}=\frac{2}{4}=\frac{1}{2}\nonumber$ 2. What is the ratio of the number of gallons of water in the cylindrical basin to the rectangular basin?$\frac{400,000\,\, gallons}{200,000\,\, gallons}=\frac{4}{2}=\frac{2}{1}=2\nonumber$ 3. The price of (some chemical) recently increased from $10.80/case to$13.50/case. Find the ratio of the increase in price to the original price. The increase in price is determined by subtracting the original price from the ending price:increase in price = $13.50-$10.80 = \$2.70. The ratio of the increase in price to the original price = $\frac{\2.70}{\10.80}=0.25\, \, \text{or}\, \, \frac{1}{4}$ 5.02: Proportions A proportion determines the relationship between two variables as it relates to the magnitude or size of the variables. A proportional relationship shows that two ratios are equivalent such that as one amount changes, another amount changes by a relative amount. To solve proportion problems, we set up an equation such that two ratios are equivalent: $\dfrac{\text{One characteristic from one item}}{\text{A second characteristic from the same item}}=\dfrac{\text{the same first characteristic from a second item}}{\text{the same second characteristic from the second item}} \label{ratio}$ Example $1$ Seven containers of a chemical costs 125. If the cost of the containers is proportional, meaning the unit price does not change, determine the cost of 12 containers of the same chemical. Solution Let’s begin by setting up the fractions like in Equation \ref{ratio}: \begin{align*} \dfrac{\text{Number of containers}}{\text{Cost of those containers}} &=\dfrac{\text{Number of another set of containers}}{\text{Cost of those containers}} \[4pt] \dfrac{7\, \text{containers}}{\125} &=\dfrac{12\, \text{containers}}{x} \end{align*} To solve for $x$ we can use one of two methods: Method 1: Solve for $x$ by isolating the $x$ (using information learned in Unit 3) Multiply both sides of the equation by $x$: $\dfrac{7}{125}x=12 \nonumber$ Multiply both sides of the equation by125: \begin{align*} 7x &=12\cdot 125 \[4pt] 7x&=1500 \end{align*} Divide both sides of the equation by 7 containers: $x=\dfrac{1500}{7}=\214.29 \nonumber$ Method 2: Use cross multiplication: Multiply the numerator of the first fraction by the denominator of the second fraction and set it equal to the multiplication of the numerator of the second fraction by the denominator of the first fraction. \begin{align*} \left(7 \, \text{containers}\right)\cdot \left(\x\right) &=\left(12 \, \text{containers} \right)\cdot \left(\125\right) \[4pt] 7x &=1500 \[4pt] x&=\dfrac{1500}{7} \[4pt] &=\214.29 \end{align*} Hence, the cost of the 12 containers is \$214.29. Example $2$ We want to estimate the number of fish in a pond. Suppose we capture 280 fish, tab them, and throw them back into the pond. After a couple of days, we go back to the pond and capture 420 fish, of which 28 are tagged. Estimate the number of fish in the pond. Example $3$ We wish to mix a solution of hypochlorite and water by dissolving 4.8 pounds of hypochlorite in 70 gallons of water. For the same concentration, how many pounds of hypochlorite should we dissolve in 20 gallons of water? Solution Let’s begin by setting up the fractions like in Equation \ref{ratio}: \begin{align*} \dfrac{\text{Number of pounds of hypochlorite}}{\text{Number of gallons of water}}&=\dfrac{\text{Number of pounds of hypochlorite}}{\text{Number of gallons of water}} \[4pt] \dfrac{4.8\, \text{lbs}}{70\, \text{gal}} &=\dfrac{x\, \text{lbs}}{20\, \text{gal}} \[4pt] \left(4.8 \, \text{lbs}\right)\left(20\, \text{gal}\right) &=\left(70\, \text{gal}\right)\left(x \, \text{lbs}\right) \[4pt] 96 &=70x \[4pt] \dfrac{96}{70} &=x \[4pt] x &=1.4\, \text{lbs} \end{align*} Hence, we need 1.4 pounds of hypochlorite to dissolve in 20 gallons of water to create the same concentration.

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/05%3A_Ratios_Proportions_and_Percentages/5.01%3A_Ratios.txt

In Unit 1, we learned how to convert between fractions, decimals, and percentages. We also learned that a percent calculated $\Large{Percent}=\dfrac{Part}{Whole}\cdot 100\%$ In this unit, we will use percentages in applications. We will concentrate on the following types of calculations which can be derived by rewriting the formula above (as learned in Unit 3): • Calculating a percent of an amount: $\left(percentage\right)\left(whole\right)=part$ • Determine the percent based on the part and the whole: $\frac{Part}{Whole}\cdot 100\%=Percent$ • A value is a certain percent of a number: $whole=\frac{part}{percent}$ Examples: 1. 52% of 560 is what number? Since “of” means multiplication, we have $\left(52\%\right)\left(560\right)=a\,\, number$, so let’s convert 52% to a decimal by dividing 52 by 100 or by moving the decimal place two units to the left to obtain 0.52, hence $\left(52\%\right)\left(560\right)=\left(0.52\right)\left(560\right)=291.2$. As a result, 52% of 560 is 291.2. 1. 32 is what percent of 420? In this problem, we need to calculate the percent and we have the part, which is 32, and the whole, which is 420. Hence $Percent=\frac{32}{420}\cdot 100\%=0.076\cdot 100\%=7.6\%$ (using two significant figures; see Unit 5). 1. 23 is 12% of what number? Round the final answer to the nearest hundredth. (Unit 5) In this problem, we are given the part and the percent and need to determine the whole, so we use: $whole=\frac{part}{percent}=\frac{23}{12\%}=\frac{23}{0.12}=191.67$ Percentages can be used in the Water Industry in many ways. Below are a few applications of percentages and ratios. • The volatile content of raw sludge can be calculated as a rate, proportion, or a percent. Generally, we will use a percent to represent the volatile content of raw sludge by calculating the reduction of volatile matter using the following formula: $\text{Volatile Solids Reduction (%) } = \frac{\left(Value\,\, IN\right)-(Value\,\, OUT)}{\left(Value\,\, IN\right)-[(Value\,\, IN)(Value\,\, OUT)]}\cdot 100\%$ When the volatile solids reduction is between 50%-60%, it is a good or healthy anaerobic digester. Any amount less than 50% is not reducing the volatile solids enough. NOTE: The fraction portion of this formula represents the rate or proportion. By multiplying by 100% we obtain the percentage. Also, note that the Value IN and Value OUT are decimal values between 0 and 1. Example: The volatile content of raw sludge is 68.2% while the digester sludge is 55.6%. Calculate the volatile solids reduction and determine if the reduction is a healthy amount. \begin{align} \text{Volatile Solids Reduction (%) }&= \frac{\left(Value\,\, IN\right)-(Value\,\, OUT)}{\left(Value\,\, IN\right)-[(Value\,\, IN)(Value\,\, OUT)]}\cdot 100\% \ &=\frac{0.682-0.556}{0.682-\left(0.682\right)\left(0.556\right)}\cdot 100\% \ &=\frac{0.126}{0.682-0.379}\cdot 100\% \ &=\frac{0.126}{0.303}\cdot 100\% \ &=0.4158\cdot 100\%=41.6\% \end{align} Since 41.6% is not between 50% and 60%, this is considered to not be a good reduction of waste solids. • The efficiency of water can be calculated using the following formula: $Efficiency=\frac{\left(Value\,\, IN-Value\,\, OUT\right)}{Value\,\, IN}\cdot 100\%$ where the Value IN corresponds to the water received from another water system through intertie and Value OUT corresponds to water supplied to another water system through an intertie. [Intertie as defined by Merriam- Webster Dictionary, “an interconnection permitting passage of current between two or more electric utility systems” such as in a share federal-state water system. NOTE: The fraction portion of this formula represents the rate or proportion. By multiplying by 100% we obtain the percentage. Example: Calculate the efficiency (as a percent) of removing BOD (Biological Oxygen Demand) at a wastewater treatment plant if the influx of BOD is 215 mg per liter and the outflow is 18 mg per liter. \begin{align} \text{Efficiency}&=\frac{\left(Value\,\, IN-Value\,\, OUT\right)}{Value\,\, IN}\cdot 100\%\ &= \frac{\left(215 \frac{mg}{L}-18\frac{mg}{L}\right)}{215\frac{mg}{L}}\cdot 100\%\ &=\frac{197\frac{mg}{L}}{215\frac{mg}{L}}\cdot 100\%\ &=0.916\cdot 100\% \ &=91.6\% \end{align} Hence, the efficiency of removing BOD at the wastewater treatment plant is 91.6%.

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/05%3A_Ratios_Proportions_and_Percentages/5.03%3A_Percentages.txt

In the Water Industry, often it will be important to calculate perimeter, circumference, area, volume, or surface area (lateral area) of various objects. Let’s start by defining each geometric calculation. Definitions Perimeter: The linear measurement or distance around the outside of a two-dimensional object such as a square, rectangle, triangle, etc. The units are expressed as a linear measurement such as inches, feet, yards, miles, millimeters, centimeters, meters, kilometers, etc. $P=length\,\, of\,\, side\,\, 1+length\,\, of\,\, side\,\, 2+length\,\, of\,\, side\,\, 3+length\,\, of\,\, side\,\, 4+\dots$ Circumference: The linear measurement around the outside of a circle. The units are expressed as a linear measurement such as inches, feet, yards, miles, millimeters, centimeters, meters, kilometers, etc. NOTE: Circumference is the name we use to represent the perimeter of a circle. $C=\pi (diameter) \,\, \text{or} \,\, C=2\pi (radius)$ Area (or Surface Area or Lateral Area): The measurement of the amount of space inside a 2-dimensional object or on the surface of a 3-dimensional object. The units are expressed as square linear units such as square inches (in${}^{2}$), square meters (m${}^{2}$), square feet (ft${}^{2}$), etc. The formula for area depends on the object, so let’s start with the area of some common objects: Geometric Measurement Formula Shape Area of a rectangle $A=(length)(width)$ Area of a triangle $A=\frac{1}{2}(base)(height)$ Area of a circle $A=\pi(radius)^2$ or $A=(0.785)(diameter)^2$ Area of a trapezoid $A=\frac{1}{2}(base \,\,1+base\,\, 2)(height)$ Volume: The measurement of the amount of space inside a 3-dimensional object. The units are expressed as cubic linear units such as cubic inches (in${}^{3}$), cubic meters (m${}^{3}$), cubic feet (ft${}^{3}$), etc. The general formula for volume is: $Volume=(Area\,\, of\,\, a\,\, surface)(height\,\, or\,\, length)$ The formula for volume depends on the object, so let’s start with the volume of some common objects: Geometric Measurement Formula Shape Volume of a Rectangular Box or Prism $V = (length)(width)(height)$ Volume of a Cylinder $V=\pi(radius)^2(height)$ or $V = (0.785)(diameter)^2(height)$ Volume of a Cone $V = \frac{1}{3} \pi(radius)^2(height)$ or $V = \frac{1}{3} (0.785)(diameter)^2(height)$ Volume of a Sphere $V = \frac{4}{3} \pi(radius)^3$ or $V=\frac{2}{3}(0.785)(diameter)^3$ Volume of a Triangular Prism $V=(Area\,\, of\,\, the\,\, triangular\,\, surface)(depth)$ or $V=\frac{1}{2} (base)(height)(depth \,\, or \,\, width)$ Volume of a Trapezoidal Prism $V = (Area \,\, of\,\, the \,\, trapezoidal \,\, surface)(depth)$ or $V=\frac{1}{2}(base \,\, 1+base\,\, 2)(height)(depth \,\, or\,\, width)$ 6.02: Examples 1. Calculate the perimeter (or circumference if appropriate) and area of the following shapes: 1. Calculate the perimeter and area of the rectangle using the figure below. \begin{aligned} \text{Perimeter} &= \text{sum of the lengths of the sides}\ &= \text{14 in+5 in+14 in+5 in=2(14 in)+2(5 in)} \ &= \text{ 28 in+10 in=38 in}\end{aligned} Area = (length)*(width) = $\left(14\,\, in\right)\left(5\,\, in\right)=70\,\, in^2$ 1. Calculate the circumference and area of the circle using the figure below. Circumference = $\pi \left(diameter\right)=\pi \left(6\,\, cm\right)=\left(3.14\right)\left(6\,\, cm\right)=18.84\,\, cm$ Area = $\left(0.785\right){\left(diameter\right)}^2=\left(0.785\right){\left(6\,\, cm\right)}^2=\left(0.785\right)\left(36\,\, cm^2\right)=28.26\ cm^2$ 1. Calculate the area of the figures below. 1. A triangle with height of 7 meters and a base of 15 meters. Area = $\frac{1}{2}\left(base\right)\left(height\right)=\frac{1}{2}\left(15\,\, m\right)\left(7\,\, m\right)=\frac{1}{2}\left(105\,\, m^2\right)=52.5\,\, m^2$ 1. A trapezoid with a height of 5 feet and bases of 3 feet and 10 feet. \begin{aligned}\text{Area} &= \frac{1}{2}(base\,\, 1+base\,\, 2)(height) \ &= \frac{1}{2} (3\,\, ft+10\,\, ft)(5\,\, ft) \ &= \frac{1}{2}(13\,\, ft)(5\,\, ft) \ &= \frac{1}{2} \left(65\,\, ft^2\right)=32.5\,\, ft^2 \end{aligned} 1. Calculate the perimeter and area of the following figure 1. Calculate the perimeter. Since the perimeter is the distance around the outer edges, we can calculate the distance across the top edge to be the sum of the lower horizontal edges, namely $2\,\, m\,\, +\,\, 4\,\, m\,\, +\,\, 2\,\, m\,\, =\,\, 8\,\, m$ Next, add the lengths of the outer edges to obtain \begin{aligned} \text{Perimeter} &=8\,\, m+6\,\, m+2\,\, m+5\,\, m+4\,\, m+5\,\, m+2\,\, m+6\,\, m \ &= 8\,\, m+2\left(6\,\, m\right)+2\left(2\,\, m\right)+2 \left(5\,\, m\right)+4\,\, m \ &=8\,\, m+12\,\, m+4\,\, m+10\,\, m+4\,\, m\ &=38\,\, m\end{aligned} 1. Calculate the area. Using a dashed line, divide the figure into two rectangles by drawing a horizontal line through the figure at the 2 m markings Next, find the area of each figure and add the results to obtain the area of the original figure. The area of the upper rectangle = A${}_{1}$ = $\left(6\,\, m\right)\left(8\,\, m\right)=48\,\, m^2$ The area of the lower rectangle = A${}_{2}$ = $\left(5\,\, m\right)\left(4\,\, m\right)=20\,\, m^2$ Total Area = A${}_{1}$ + A${}_{2}$ = $48\,\, m^2+20\,\, m^2=68\,\, m^2$ 1. Calculate the perimeter and area of the figure below. 1. Calculate the perimeter. Since the perimeter is the distance around the outer edges, we add the lengths of the edges to obtain \begin{aligned}\text{Perimeter} &= 4\,\, cm+2\,\, cm+3\,\, cm+2\,\, cm+4\,\, cm+5\,\, cm+11\,\, cm+5\,\, cm \ &= 2\left(4\,\, cm\right)+2\left(2\,\, cm\right)+3\,\, cm+2\left(5\,\, cm\right)+11\,\, cm \ &= 8\,\, cm+4\,\, cm+3\,\, cm+10\,\, cm+11\,\, cm\ &=36\,\, cm\end{aligned} 1. Calculate the area. We can compute the area of this figure in one of two ways, either using addition or by using subtraction. Let’s investigate both methods. 1. Using Addition Divide the figure into three rectangles by drawing a dashed line from the left side of the figure through to the right side of the figure, connecting at the 3 cm line. Calculate the area of each rectangle and add the results; let’s notice that the two upper rectangles are the same size Area of small rectangle $=\left(4\,\, cm\right)\left(2\,\, cm\right)=8\,\, cm^2$ Area of large rectangle $=\left(3\,\, cm\right)\left(11\,\, cm\right)=33\,\, cm^2$ Total area $=8\,\, cm^2+8\,\, cm^2+33\,\, cm^2=49\,\, cm^2$ 1. Using Subtraction Find the area of the outer rectangle and subtract the area of the rectangular hole, so now let’s draw a horizontal dashed line across the top opening of the figure Next, let’s find the area of the larger outer edge rectangle Area of large rectangle $=\left(5\,\, cm\right)\left(11\,\, cm\right)=55\,\, cm^2$ Area of the rectangular hole $=\left(2\,\, cm\right)\left(3\,\, cm\right)=6\,\, cm^2$ \begin{aligned} \text{Total Area} &= \text{Area of large outer rectangle – Area of the rectangular hole} \ &=55\,\, cm^2-6\,\, cm^2=49\,\, cm^2\end{aligned} 1. A rectangular pool measures 28 feet by 52 feet. Surrounding (and bordering) the basin is a path 3 feet wide. Find the area of the path. First, let’s draw a figure to depict the scenario. Let’s start by drawing a rectangle to represent the pool. Next, let’s draw the 3 ft wide border around the pool to represent the path. The path is represented by the shaded region. The outer edge of the path creates a larger rectangle whose length is the length of the pool plus twice the width of the path or 52 ft + 2(3 ft) = 58 ft. The width of the outer edge of the path is the width of the pool plus twice the width of the path or 28 ft + 2(3 ft) = 34 ft. To obtain the area of the path, find the area of the outer edge - the area enclosed by the pool = area of the path \begin{aligned} \text{Area of the path} &= \left(58\,\, ft\right)\left(34\,\, ft\right)-(28\,\, ft)(52\,\, ft) \ &=1972\,\, ft^2-1456\,\, ft^2\ &=516\,\, ft^2 \end{aligned} 1. Calculate the lateral area (surface area) of a triangular prism as shown below There are five sides or surfaces to this triangular prism. Two of the sides are triangles of the same size, namely with a height of 6 inches and a base of 8 inches and the other three sides are rectangles, the left face is 6 inches by 7 inches rectangle, the bottom face is 8 inches by 7 inches rectangle, and the right-side face is 10 inches by 7 inches rectangle. To calculate the lateral area or surface area, we find the area of all the surfaces and add the results Area of the two triangles $=2\left[\frac{1}{2}\left(8\,\, in\right)\left(6\,\, in\right)\right]=48\,\, in^2$ \begin{aligned}\text{Area of the three rectangles} &=\left(6\,\, in\right)\left(7\,\, in\right)+\left(8\,\, in\right)\left(7\,\, in\right)+\left(10\,\, in\right)\left(7\,\, in\right) \ &=42\,\, in^2+56\,\, in^2+70\,\, in^2\ &=168\,\, in^2\end{aligned} Lateral area $=48\,\, in^2+168\,\, in^2=216\,\, in^2$ More examples using volume of three-dimensional objects 1. Calculate the volume of the rectangular prism with dimensions 2 yds X 6 yds X 7 yds. $Volume=\left(length\right)\left(width\right)\left(height\right)=\left(2\,\, yds\right)\left(6\,\, yds\right)\left(7\,\, yds\right)=84\,\, yds^3\nonumber$ 1. Calculate the volume of a triangular prism as shown below. $V=\frac{1}{2}\left(base\right)\left(height\right)\left(depth\,\, or\,\, width\right) \nonumber$ $V=\frac{1}{2}\left(8\,\, in\right)\left(6\,\, in\right)\left(7\,\, in\right)=168\,\, in^3 \nonumber$ 1. Calculate the volume of a sphere with a diameter of 15.6 mm. $V=\frac{2}{3}\left(0.785\right){\left(diameter\right)}^3=\frac{2}{3}\left(0.785\right){\left(15.6\,\, mm\right)}^3=\frac{2}{3}\left(0.785\right)\left(3796.416\,\, mm^3\right)=1986.8\,\, mm^3 \nonumber$ 1. Calculate the volume of the object below (not drawn to scale) \begin{aligned} \text{Total Volume} &=\text{Volume of the cylinder + Volume of the cone} \ \text{Volume of cylinder} &=\left(0.785\right){\left(diameter\right)}^2\left(height\right) \ &=\left(0.785\right){\left(2\,\, m\right)}^2\left(16\,\, m\right) \ &= \left(0.785\right)\left(4\,\, m^2\right)\left(16\,\, m\right) \ &=\left(0.785\right)\left(64\,\, m^3\right)\ &=50.24\,\, m^3\end{aligned} \begin{aligned} \text{Volume of cone} &=\frac{1}{3}(0.785)\left(diameter\right)^2\left(height\right) \ &= \frac{1}{3}\left(0.785\right)\left(2\,\, m\right)^2\left(3\,\, m\right)\ &= \frac{1}{3} \left(0.785\right)\left(4\,\, m^2\right)\left(3\,\, m\right)\ &=\frac{1}{3} \left(0.785\right)\left(12\,\, m^3\right)\ &=3.14\,\, m^3\end{aligned} \begin{aligned} \text{Total Volume} &= \text{Volume of the cylinder + Volume of the cone}\ &=50.24\,\, m^3+3.14\,\, m^3 \ &=53.38\,\, m^3 \end{aligned}

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/06%3A_Geometry/6.01%3A_Definitions.txt

In the Water Industry, an important skill is reading and interpreting graphs and charts. There are many types of graphs and charts such as pie charts, bar graphs, histograms, line graphs, dials, gauges, etc. When reading and interpreting graphs, it is very important to read the labels on the graph or chart and to consider the units (if any). 07: Reading and Interpreting Graphs Line graphs: Line graphs are commonly used in the water and wastewater industry. They are quick and easy to create and read. It is important to read the labels on the horizontal and vertical axes and to read the graph from left to right. To read information on a line graph, locate a point on the line graph, find the corresponding value on the horizontal and vertical axes. Bar graphs: A bar graph can consist of vertical or horizontal bars that can display numerical or categorical data. To read a bar graph, for each category, locate the height (or length) of the bar and read the scale or value. Some bar graphs will consist of double bars or multiple bars for each category. This allows information to be compared at a quick glance. Pie charts: A pie chart is generally used to show percentages or proportions of categories as they relate to each other. Each wedge in a pie chart represents a category and the size of the wedge represents the percentage or proportion of that category. Semi-log or log-log graphs: A semi-log graph has logarithmic scales on one axis and a numeric scale on the other axis. A log-log graph has logarithmic scales on both the horizontal and vertical axes. They can be used for showing the flow rate. When reading a graph, be sure to pay close attention to the scale of the axes and/or picture. The markings on the axes or picture indicate the size of the numerical values depicted on the graph. 7.02: Examples Examples: 1. A city’s sanitary sewer budget for the year is \$350,000. The budget has been divided into five categories: Personnel, contractual, power, benefits and insurance, and equipment. Based on the pie chart, which category has the larger proportion of the budget been allocated to? Which category has the least allocation? Which two categories have similar allocations? What dollar amount has been allocated for power? Solution We can visually see that the largest part of the pie is allocated to personnel at 43% and the smallest part of the pie is allocated to equipment at 1%. The two pieces of the pie that are similar in size are for contractual and benefits and insurance which represent 22% and 20% respectively. It is also important to note that these percentages are based on the \$350,000 budget. Hence the amount of money allocated for power is 14% of \$350,000 or .14(\$35,000) = \$4900. 1. Using the bar graph below, answer the following questions: 1. What general information is provided in the bar graph? 2. Which year had the most liters of treated water? 3. Which year had the least liters of treated water? 4. In which year was 8,000,000,000 liters of water treated? 5. The amount of treated water increased between which years? 6. The amount of treated water decreased between which years? 7. Which years had approximately the same number of treated liters of water? Solution 1. What general information is provided in the bar graph? The number of liters of water treated each year between 1998 and 2012 2. Which year had the most liters of treated water? 2009 3. Which year had the least liters of treated water? 1998 4. In which year was 8,000,000,000 liters of water treated? 2006 5. The amount of treated water increased between which years? 1998-2009 6. The amount of treated water decreased between which years? 2009-2011 7. Which years had approximately the same number of treated liters of water? 2008 and 2011 1. Using the line graph below, answer the following questions: 1. What general information is provided in the line graph? 2. The number of gallons of water in the pool appear to increase, decrease, or remain the same as the number of gallons of Sodium HypoChlorite increases? 3. How many gallons of Sodium HypoChlorite are needed to shock 25,000 gallons of water? 4. How many gallons of water can 4 gallons of Sodium HypoChlorite shock? 5. What is the maximum point on the graph and what does it represent? Solution 1. What general information is provided in the line graph? The number of gallons of Sodium HypoChlorite (a type of chlorine) that are needed to shock a certain number of gallons of water in a swimming pool. 2. The number of gallons of water in the pool appear to increase, decrease, or remain the same as the number of gallons of Sodium HypoChlorite increases? Since the line graph is going up from left to right, the number of gallons of water in the pool is increasing as the number of gallons of Sodium HypoChlorite used increases. 3. How many gallons of Sodium HypoChlorite are needed to shock 25,000 gallons of water? Reading the vertical axis, we can find 25,000 gallons of water, move to the right to find the point on the graph and read the corresponding number on the horizontal axis, which is 3 gallons of Sodium HypoChlorite. 4. How many gallons of water can 4 gallons of Sodium HypoChlorite shock? Reading the horizontal axis, we can find 4 gallons of Sodium HypoChlorite, go up the graph to find the point on the graph and read the corresponding number on the vertical axis, which is 35,000 gallons of water. 5. What is the maximum point on the graph and what does it represent? The highest point on the graph is at (5, 50000). Note: the horizontal number is written first in a point and the vertical axis number is written second. This point means we need 5 gallons of Sodium HypoChlorite to shock 50,000 gallons of swimming pool water.

textbooks/workforce/Water_Systems_Technology/Mathematics_for_Wastewater_Management_(Brooks)/07%3A_Reading_and_Interpreting_Graphs/7.01%3A_Types_of_Graphs.txt

Water Systems Technology is a program designed to provide the student with enough information to build a successful and lasting career in the water and wastewater industries. It is a program that has been developed by professionals within the industry and within academia. Upon successful completion of the program and after completing any required general education course work, the student can earn an Associate of Science degree in Water Systems Technology. In addition, each course provides supplemental course work hours required for renewal of existing certifications in the water and wastewater industries and many provide specialized training coursework to qualify students to take state certification exams. The program has several general topic course options, includes coursework related to waterworks mathematics, and has specialized courses covering water distribution, water treatment, and wastewater. Introduction to Water Systems Technology (Water 020) is a general overview course of the entire Water Systems Technology program. Topics covered include the requirements to obtain a career in the water and wastewater industries, and an overview of specific disciplines covered throughout the program. The various courses will provide the student a broad understanding of both the drinking water and wastewater industries, as well as specific technical background. This course and the accompanying text will provide the student with enough information to determine if “water” is the type of career for them. Water is a vital resource to sustain both animal and plant life. It is a resource that many take for granted. As long water flows out of the faucets within a home, many people don’t think much more about it. However, if the flow of water stops, people take notice. Think for a moment about all the things we use water for: washing, bathing, drinking, cooking, cleaning, restrooms, brushing teeth, the list goes on and on. And this is only some of the indoor water usage. Most of the water used by residential consumers is outdoors. Whether it is landscaping, swimming pools, washing cars, or growing crops, outdoor water use can account for up to 70% of a customer’s water usage. In addition, commercial and industrial businesses use water for a variety of different processes. Some industries might use millions of gallons of water a year while others might only use a few thousand gallons. Take for example an insurance office with 10 employees. More than likely the office will have a restroom and perhaps a small kitchen area. The water use at this type of business would probably be rather low. Maybe a couple hundred gallons of water flushed down the toilet and a couple pots of coffee a day might be all. Now, take the example of chemical manufacturing plant with 100 employees. In addition to restrooms and possibly a kitchen, this type of business might have boilers, water treatment and conditioner systems, and may also use a lot of water in the production of chemicals. You can see how water use can vary from business to business. Lastly, and the biggest user of water, is the agricultural industry. In California, growing crops throughout the state can account for up to 80% of the total water use. Water is not only a health and safety need of millions of people, it is a vital resource for keeping the economic system flourishing. Some of these topics and a discussion of the various uses of water will be covered throughout this course. First, we will take a look at the classes offered in the Water Systems Technology program. There are 11 different classes, including Water 020. Each class focuses on different topics in order for the student to gain unique perspectives on the water industry as a whole and to gain an understanding on specific areas to help the student become a certified operator within specific fields. The courses are broken into several broad categories: General Topics • Water 020 – Introduction to Water Systems Technology • Water 032 – Water Supply • Water 035 – Water Quality Mathematics • Water 030 – Introduction to Waterworks Mathematics • Water 031 – Advanced Waterworks Mathematics Drinking Water Distribution • Water 040 – Water Distribution Operator I • Water 041 – Water Distribution Operator II Drinking Water Treatment • Water 050 – Water Treatment Operator I • Water 051 – Water Treatment Operator II Wastewater Treatment • Water 060 – Wastewater Treatment Processes I • Water 061 – Wastewater Treatment Processes II The following are general descriptions of each course within the program. Water 020 aims to introduce you to the program as a whole and provide a high-level overview of the various topics covered throughout the program. Water 020 – Introduction to Water Systems Technology This course explores the technologies, potential career opportunities, and the State of California certification requirements in the water industry. Introduction to Water Systems Technology is an introductory course that introduces the student to the various career opportunities within the industry. The course also provides a brief description and overview of each course within the program. Although Water 020 is a required course to earn an A.S. degree in Water System Technology, it is designed for students that are not currently in the industry and provides a high-level overview for those seeking a new career path. Water 020 begins with a general description of the entire Water Systems Technology program, with a brief introduction to each of the courses offered in the program. The course reviews the requirements of Operator Certification regulations that were part of the 1996 Safe Drinking Water Act Amendments. It examines dozens of career opportunities and assists the student with preparing an effective cover letter, résumé, and application for entry-level positions within the industry. Other topics of discussion include drinking water and wastewater quality, treatment, distribution, supply, use, conservation, and recycling. Water 030 – Waterworks Mathematics Water 030 is an introduction to waterworks mathematics. Math plays an important role in water systems technology and this course prepares the student for basic level water related math problems. The course begins with a review in basic mathematical principles such as fractions, decimals, percentages, and equations. Memorization is discouraged in this course, which is why the first few weeks are designed to reintroduce basic math topics to build a foundation for water-related concepts. There is plenty of information to memorize within this program, so understanding how to “solve” math problems is a more efficient approach than memorizing. The course focuses on UNITS as an underlying theme. Numbers without units are meaningless and in the word of water units such as gallons, cubic feet, miles, inches, minutes, liters, acre-feet, and million gallons are used routinely. Understanding how to use these types of units and the concepts introduced in this course will give the student enough background to pass the math portion of lower level certification exams and a foundation to tackle more complex and advanced water related math topics. Entry-level topics include the calculation of areas, volumes, and circumferences, chemical dosage, pressure, flow rate, and beginning treatment process mathematics. There are no prerequisites for this course, but being able to solve elementary math level questions is desired. However, even if the student has taken a math class in years, the first few weeks of this course will bring back memories of teachers of the past! Water 031 – Advanced Waterworks Mathematics Water 031 builds on the topics learned in Water 030. Water 030 is a prerequisite for taking Water 031. However, if a student has previously taken a college level math course or has strong math skills they can petition to “test out” of the Water 030 prerequisite. If approved, a Water 030 test will be administered. If the student passes the exam they are allowed to attend Water 031 without completing Water 030. Water 031 moves at a rapid pace and spends only a small amount of time reviewing information learned in Water 030. The course covers math concepts and ideas preparing the student for advanced certification exams. Discussions of advanced water distribution and treatment processes and concepts are also incorporated into each lesson in order to present practical applications of the math topics. The course provides advanced instruction on topics covered in Water 030, such as chemical dosage, treatment processes, flow rates, pressure, and volume calculations. In addition, the course introduces new concepts in the areas of horsepower, pump efficiency, blending, and budget calculations. Water 032 – Water Supply Water 032 takes an overall look of water supplies. This course explores the sources of drinking water supplies with a special emphasis of water in California. The course looks at the various uses of water from residential, commercial, and industrial, to irrigation landscaping water demands. Discussions will include the differences between surface and groundwater supplies, and emergency water sources. Water quality and source water protection are other topics covered in this broad overview course of water supply principles. Water 032 begins with a general overview of the hydrologic water cycle, which illustrates the point of water’s endless cycle through various phases (gas, liquid, and solid.) The course wraps up with a discussion of water conservation and alternative sources of supply such as recycled water. Water 035 – Water Quality Water quality is one of the most important aspects of drinking water. There are numerous state and federal regulations that water utilities must adhere to. It is the number one issue customers are most concerned about. Water 035 examines the chemical and microbiological principles of water and applies them to drinking water quality. The course also focuses on major water quality regulations and how and why they are set at their respective values. The remaining courses offered in Water Systems Technology are grouped by category within the water industry. These three (3) main disciplines within the industry are Water Distribution, Drinking Water Treatment, and Wastewater. Whether the student wants to work in distribution, treatment, or wastewater, all three of these require state certification. Each of these courses prepares the student for their respective certification exams as well as valuable information within each discipline to help the student succeed as a water professional. Water 040 – Water Distribution Operator I Water 040 introduces basic concepts and processes of drinking water distribution systems. It provides a wide range of knowledge including a general background of drinking water sources, regulations, water system design, and various distribution system components and appurtenances. Water distribution is followed from the source to the tap in this introductory level course. Water 040 also assists the student in the preparation of Division of Drinking Water Distribution Operator Certification Exams for Grades D1 and D2. These certification exams require a broad range of entry-level knowledge of water distribution systems. Water 040 is designed to provide the knowledge and understanding needed to pass these exams and to provide the student with general understanding of how distribution systems operate. Water 041 – Water Distribution Operator II Water 041 builds on the knowledge gained in Water 040 and presents the student with an intermediate to advanced level understanding of water distribution systems. Topics covered in Water 040 will be expanded in Water 041 creating a deeper understanding of how the various systems are inter-related. Water 041 will assist the student in their preparation for Division of Drinking Water Certification Exams for Grades D3 and D4. These intermediate and advanced certification exams take the practices and principles of the Grade D1 and D2 exams and investigates a more in depth understanding of those topics. Although Water 040 is not a prerequisite for taking Water 041, it is recommended. Water 050 – Water Treatment Plant Operation Processes I Similar to Water 040, Water 050 introduces basic concepts and processes to drinking water treatment. Basic operating principles and techniques of direct filtration and conventional surface water treatment plant processes of coagulation, flocculation, sedimentation, and filtration. In addition, an overview and basic discussion of various disinfection processes are covered. Water 050 will assist the student in their preparation for Division of Drinking Water Certification Exams for Grades T1 and T2. These certification exams require a broad range of entry-level knowledge of drinking water treatment systems. Water 050 is designed to provide the knowledge and understanding needed to pass these exams and to provide the student with the understanding of how drinking water treatment plants operate. Water 052 – Water Treatment Plant Operation Processes II Similar to Water 041, Water 052 builds on the knowledge gained in Water 050. Water 050 topics are discussed at the intermediate and advanced levels of understanding. Additional water treatment principles are introduced and a complete understanding of drinking water treatment processes is expected. Water 052 will assist the student in their preparation for Division of Drinking Water Certification Exams for Grades T3 and T4. These intermediate and advanced certification exams take the practices and principles of the Grade T1 and T2 exams and looks into a more in-depth understanding of those topics. Although Water 050 is not a prerequisite for taking Water 052, it is recommended. Water 060 – Wastewater Treatment Processes I Water 060 continues the pattern of the distribution and drinking water treatment course. Water 060 is an introduction to wastewater treatment plant operations. After water is used by the consumer, it typically flows through an underground sewer piping system to a Water Reclamation Plant (WRP) or Wastewater Treatment Plant (WTP) for treatment before it is discharged back into the environment. This course takes an introductory look at the basic treatment processes wastewater goes through. Similarly to drinking water certification exams, there are a series of certification exams for wastewater treatment plant operators. These exams are administered by the State Water Resources Control Board. This course is designed to assist the student in preparation for the introductory exams. Water 061 – Wastewater Treatment Processes II In Water 061 the treatment processes discussed in Water 060 will be expanded upon to provide the student with intermediate and advanced level knowledge of wastewater treatment principles and practices. Water 061 is designed to assist the student in preparation for the intermediate and advanced certification exams. Although Water 060 is not a prerequisite for taking Water 061, it is recommended. Water Systems Technology Program The program has an overarching goal referred to as Student Learning Outcome (SLO) that states, “Students will be able to demonstrate proficiency in the core skills and knowledge required for employment in the water industry.” In order to earn a Certificate of Achievement in Water Systems Technology, a total of 28 units are required. A student must take fifteen (15) “core” units, plus six (6) additional elective units. In addition to the program certificate, a student can earn an Associate in Science Degree in Water Systems Technology after completing the 28 program units plus the general educational requirements. The program requires the following fifteen (15) units; • Water 020 – Introduction to Water Systems Technology • Water 030 – Waterworks Mathematics • Water 031 – Advanced Waterworks Mathematics • Water 032 – Water Supply • Water 035 – Water Quality The remaining six (6) units are made up of two of the following; • Water 040 – Water Distribution Operator I • Water 041 – Water Distribution Operator II OR • Water 050 – Water Treatment Plant Operation Processes I • Water 052 – Water Treatment Plant Operation Processes II OR • Water 060 – Wastewater Treatment Processes I • Water 061 – Wastewater Treatment Processes II As with all “classroom” learning, it is only part of what is required to be a successful water worker. Education is a valuable resource and can provide general knowledge and information about process and theories, but nothing can compare to actual on the job training and experience. In any industry or any field, job experience is something most employers would like to see in an applicant. However, in order to gain on the job experience, you must be employed. Sometimes in order to get employed, you need experience. You can see the apparent problems with this conundrum and you may experience it when you start searching for work. When applying for a job, there are a couple of things that can be done to help combat this challenge. First, you may have to start at the “bottom.” The bottom can be an entry level position or it might be a position where you have some experience but the job might not necessarily be the one you are seeking. Never lose sight of your ultimate goal but sometimes you will need to take several steps before you get there. For example, ABC Water Agency might be hiring for a Customer Service Representative and you might be looking for a Water Utility Operator position. The problem is that you do not have any experience as a utility operator. However, you might have some experience in customer service. Why not apply for the Customer Service Representative position? Sometimes, just getting your “foot in the door” is enough to help gain the experience needed. Once you start working for a water utility, you will begin to hear the terminology used, learn how the business operates, and gain a general understanding of operations. Many times it is easier to transfer from one department to another than it is getting hired from the outside. Sometimes agencies open up positions to existing employees before they start looking on the outside. Getting a job within the industry you want to work in can be the first step to getting your career started and landing the position you are seeking. Second, you can try to tailor your experience to fit with some of the required experience for a specific job. For example, you may have worked in some type of construction related business in the past. You can try and use this as experience for some field type positions. Maybe the experience is not directly related, but you can try and word the experience on a resume to fit the job or at least demonstrated some of the same qualities that a similar position might require. Preparing cover letters, resumes, and applications will be discussed later in this text. Chapter 3 of this text takes an in depth look at the various career opportunities in the industry. There are always general types of jobs in most industries such as customer service, accounting, human resources, etc. Remember, that these types of jobs might just lead into the career you are seeking. However, you might also find a very rewarding career in one of these disciplines too. Working in water and wastewater provides dozens of opportunities in a variety of different areas. Find what works for you and you’ll have a successful and productive career.

textbooks/workforce/Water_Systems_Technology/Water_120%3A_Introduction_to_Water_Systems_Technology/1.01%3A_Introduction_to_Water_Systems_Technology.txt

There are numerous regulations that pertain to the water industry as a whole. In addition to general business and accounting regulatory requirements, health and safety requirements, environmental requirements, labor requirements, etc, there is a set of regulations that specifically govern water utilities. These regulations are referred to as the Safe Drinking Water Act. The Environmental Protection Agency promulgated these regulations in the early 1970s and required states to adopt them or create similar regulations that meet the minimum requirements. The practical application of the California Safe Drinking Water Act (SDWA) encompasses the federal act and in some instances has added additional requirements that have made some of the water quality regulatory standards more stringent. California’s SDWA can be found in California Code of Regulations Title 22, Division 4 Environmental Health. Much of the SDWA deals with water quality regulations, which will be discussed in a later chapter. However, there are other operational requirements that are specified as well. In 1996, the SDWA was amended for the second time. Some of the changes included provisions for “Operator Certification” requirements. Treatment Operator certification requirements were part of the original SDWA regulations establishing the level at which water treatment facilities should be manned, the minimum qualifications for testing at five (5) different grade levels, and criteria for the renewal and revocation of certificates. The recent amendments now include the certification and recertification requirements for distribution operators at five (5) different grade levels. Operator Certification refers to requirements for both treatment and distribution operators in order for them to perform certain work. Both treatment and distribution operators are classified by five (5) different certification grade levels. Treatment Operators are listed as T1, T2, T3, T4, and T5 and Distribution Operators as D1, D2, D3, D4, and D5. T1 and D1 are the lowest certification levels and T5 and D5 are the highest. Generally entry level positions require lower level certifications such as D1, D2, T1, or T2. These positions are primarily labor related jobs and require little contact and or control of the water supply. Supervisors and managers sometimes require higher certification levels depending on their job descriptions. However, there are specific regulations that spell out minimum certification requirements for certain job related tasks. The Operator Certification regulations provide very specific requirements for becoming certified and who actually needs to be certified. In addition, there are a number of definitions. Among them are definitions for what is referred to in the regulations as “Shift” and “Chief” Operators. • Shift Operator - “Shift Operator” means a person in direct charge of the operation of a water treatment or distribution system for a specified period of the day. • Chief Operator - “Chief Operator” means the person who has overall responsibility for the day-to-day, hands-on, operation of a water treatment facility or the person who has the responsibility for the day-to-day, hands-on, operation of a distribution system. Although these definitions may seem specific, they do have some ambiguity. What if you have a distribution operator who is in charge of a certain operation for the day, but he has been told to call a supervisor before making any decisions or changes in the system. Is this person a “shift operator” per the definition above? Can a manager that is responsible for a treatment facility, but doesn’t actually work on the treatment facility be a “chief operator”? As you can see, there needs to be some clarification to these and other definitions in the regulations. The regulations do offer some clarification. For example, they specify that water systems shall utilize only certified operators to make decisions addressing the following operational activities: 1. Install, tap, re-line, disinfect, test and connect water mains and appurtenances 2. Shutdown, repair, disinfect and test broken water mains 3. Oversee the flushing, cleaning, and digging of existing water mains 4. Pull, reset, rehabilitate, disinfect and test domestic water wells 5. Stand-by emergency response duties for afterhours distribution system operational emergencies 6. Drain, clean, disinfect, and maintain distribution reservoirs (tanks) 7. Operate pumps and related flow and pressure control and storage facilities manually or by using a system control and data acquisition (SCADA) system 8. Maintain and/or adjust What determines the level of certification needed? Each treatment facility and distribution system is classified at a certain level. Meaning a treatment facility and distribution system are either classified as a T1 - T5 facility or D1 - D5 system respectively. The facility and system classification is based on a number of different parameters and in California is specified by the Division of Drinking Water (DDW), a branch within the State Water Resources Control Board of California (SWRCB.) In general, classifications are based on a point system. Treatment Facility Classification is primarily based on the type and quality of water being treated and the treatment/disinfection processes used. Distribution System Classification is based on population served. If the population served is five (5) million or less then a point system is used based on number of pressure zones, disinfectants used, size of pumping equipment, and number of storage tanks. If the point based system total exceeds 20 points then the classification is upgraded by one (1) level. Once the facility and system have been classified, the regulations then stipulate the minimum certification requirements needed by the staff. The following table specifies the minimum certification requirements for each treatment facility and distribution system classification. Treatment Facility and Distribution System Classification Minimum Certification of Chief Operator Minimum Certification of Shift Operator T1 / D1 T1 / D1 T1 / D1 T2 / D2 T2 / D2 T1 / D1 T3 / D3 T3 / D3 T2 / D2 T4 / T4 T4 / D4 T3 / D3 T5 / D5 T5 / D5 T3 / D3 How does someone become certified? There are certain requirements and prerequisites to becoming a certified operator. As previously mentioned, the first certification level (T1, D1) is the lowest level and has the least amount of requirements to become certified. Similarly, T5 and D5 are the highest certification levels and have the most requirements to reach these levels. There are two requirements for each level, one for being able to take the certification exam and the other to receive the actual certification. Let's take a look at the requirements for each certification level. Since the requirements are similar for both treatment and distribution, they will be referred to as 1 - 5 in this discussion. Level 1 - The only requirement to take a level 1 exam is a high school diploma or equivalent. A General Education Diploma (GED) is an example of something that is equivalent to a high school diploma. Even though there is no "water" related requirement to take a level 1 exam, most people would have difficulty passing the exam without having any experience or knowledge of water systems. For example, do you know the difference between a butterfly valve and a gate valve? Or, the difference between flocculation and coagulation? In order to receive the level 1 certification, the only requirement is the passing of the exam with a score of seventy percent (70%) or better. Level 2 - Level 1 is the only certification level that can be skipped. If you meet the minimum requirements of a Level 2 exam, you can skip Level 1. In order to take a Level 2 certification exam you must also have a high school diploma or equivalent. In addition, you must complete thirty six (36) hours of instruction in a water related field. A three (3) unit course meets the thirty six (36) hour requirement. The course must meet certain minimum specifications in either water supply, distribution, treatment, or similar topics. Any of these classes would provide you with the information needed to pass both a Level 1 and Level 2 exam. Therefore, it is very common for people to skip Level 1, take the required course work and then take Level 2. However, some people are curious as to the format and type of questions that are asked on these exams and take a Level 1 exam while they are also completing courses in a water related field. The requirements for receiving a level 2 certification are the same as level 1, you must pass the level 2 exam with a score of seventy percent (70%) or better. Level 3 - The requirements for taking exams and becoming certified for Level 3 and higher are a little more restrictive. In order to be able to take a Level 3 exam, you must complete two (2) thirty six (36) hour courses. One course must meet the same requirements as described for a Level 2 and the other can be a supplemental water related course. A supplemental course can be a less specific water related course such as, waterworks mathematics, water quality, or some other course that don't specifically focus on distribution or treatment. Once you successfully complete and pass the required coursework, you can take a Level 3 exam. Once you have successfully passed a Level 3 exam with a score of seventy percent (70%) or better you are not automatically eligible for a Level 3 certification. In addition to completing and passing the required two (2) courses, you must also be a certified Level 2 Operator for at least one (1) year. Therefore, you cannot skip Level 2 and become a Level 3. Level 4 - The requirements for Level 4 certifications are similar to Level 3. In addition to the two (2) classes required as Level 3, an additional supplemental course is required. Therefore, a total of three (3) thirty six (36) hour (or 3 unit) courses are required to be able to take a Level 4 exam. After successfully passing a Level 4 exam with a score of seventy percent (70%) or better and you have been a Level 3 certified operator for one (1) or more years you can obtain a Level 4 certificate. Level 5 - Four (4) thirty six (36) hour (3 unit) courses are required to qualify for taking a Level 5 exam. One (1) class must be specialized training and the other three (3) can be a supplemental course. After passing a Level 5 exam and meeting a minimum of one (1) year experience as a certified Level 4 operator a Level 5 certificate can be obtained. Division of Drinking Water Certification Exams The DDW website provides recommended reading material and an expected range of knowledge section to help prepare for the exams: www.waterboards.ca.gov/drinking_water/certlic/occupations/DWopcert.shtml In addition, this website provides all the required material to apply and prepare you to become a Certified Operator. Exams for Treatment and Distribution are each offered two times a year approximately six (6) months apart. The Treatment Exams are offered in May and November of each year with their respective filing dates March 1st and September 1st of each year. The Distribution Exams are offered in March and September of each year with their respective filing dates January 2nd and July 1st of each year. Although these are the exam schedules at the time this text was being written, the DDW website should always be visited for any updates. Treatment Exams The Treatment exams consist of multiple choice questions covering topics of Source Water, Water Treatment Processes, Operation and Maintenance of Treatment Facilities, Laboratory Procedures, Safety, Regulations, and Administrative Duties. Below is a summary breakdown of each category: Source Water • Wells and Groundwater • Surface Water and Reservoirs • Raw Water Storage • Clear Well Storage Water Treatment Processes • Coagulation • Flocculation • Sedimentation • Filtration • Disinfection • Demineralization • Corrosion Control • Iron and Manganese • Fluoridation • Water Softening • Best Available Technology Operation and Maintenance • Chemical Feeders • Pumps and Motors • Blowers and Compressors • Water Meters • Pressure Gauges • Electrical Generators Laboratory Procedures • Sampling • General Laboratory Practices • Disinfectant Analysis • Alkalinity Analysis • pH • Specific Conductance • Hardness • Fluoride • Color Analysis • Taste and Odor • Dissolved Oxygen • Algae Count • Bacteriological Analysis • Safety • Administrative Duties • Regulations In addition to all the above knowledge you must have, there are always a series of math related questions on each exam. There are typically fifteen math related questions and are usually worth two (2) points each compared to one (1) point for the general knowledge questions. The math questions range from a variety of topics and include some simple addition type computations on the lower grade exams to complex algebraic and geometric computations. Below is a brief outline of what one can expect on an exam. Math Related Computations • Areas • Volumes • Pressure • Flow • Chemical Dosage • Filtration • Horsepower • Milliamps This list is not complete and there are various topics within each of the above but it does provide you an insight into some areas of waterworks mathematics. Distribution Exams The Distribution exams consist of multiple choice questions covering topics of Disinfection, Distribution System Design, Hydraulics, Equipment Operation, Maintenance, Inspections, Drinking Water Regulations, Management, Safety, Water Mains, Piping, Water Quality, and Sources of Supply. Similarly to the Treatment Exams, there are a series of math related questions as well. In addition, there is some overlap between the information on both the Treatment and Distribution exams. Below is a summary breakdown of each category covered on the Distribution exams: Disinfection • Water Main, Well, Storage Reservoir Disinfection • Disinfection By-Products • Chloramination and Various Types of Disinfectants • Chlorine Curve Chemistry Distribution System Design and Hydraulics • System Layout • Storage Facilities • Cross Connection Control and Backflow Devices • Service Connections • System Maps • Flow Rates and Velocity • Pressure and Head Loss • Water Hammer Drinking Water Regulations • Disinfection By-Products (DBP) and Lead and Copper Rules • Maximum Contaminant Level (MCL) • Monitoring and Sampling • Total Coliform Rule (TCR) • Safe Drinking Water Act (SDWA) • Compliance • Budgets • Emergency Response • Conservation Planning • Water Rates Equipment Operation, Maintenance, and Inspections • Valves • Meters • Hydrants • Chemical Feed • Corrosion • Sensors • SCADA • Pumps • Horsepower • Water Mains • Repair and Installation • Wells Water Mains and Piping • Excavation • Installation • Joints and Fittings • Leak Detection • Repair • Material Selection Water Quality and Sources of Supply • Coliform Group • Heterotrophic Bacteria • Organic and Inorganic Compounds • pH • Hardness • Turbidity • Flushing • Disease • Groundwater • Surface Water • Sanitary Surveys This is not a complete list of all the topics covered on the Distribution Certification Exams but it is a good overview of the topics and areas that are covered. In addition, the mathematical computations you are expected to know are similar to the math questions found on the Treatment exams. Drinking Water Distribution and Treatment were both governed by California Department of Public Health (CDPH). However, in 2014 the Division of Drinking Water Programs within CDPH was moved under the State Water Resources Control Board (SWRCB) and is now referred to as Division of Drinking Water (DDW.) SWRCB also governs wastewater and the certification program for wastewater operators. In addition, the California Water Environment Association has a wastewater certification program that SWRCB recognizes. Certified Wastewater Operators can apply for an examination waiver with SWRCB if they meet certain requirements. Wastewater Exams The following information is a review of the areas of expertise and topics covered on Wastewater Certification exams: • Collection System Maintenance – This vocation deals with sewer maintenance and repair. The collection system is the from the customer’s property to the treatment plant. • Laboratory Analyst – Wastewater needs to be analyzed in a laboratory. The Laboratory Analyst has the responsibility of testing the water in the laboratory. • Environmental Compliance Inspector – Wastewater treatment facilities have a number of regulations that they must follow. The Environmental Compliance Inspector is in charge of inspecting and monitoring the wastewater that empties into the sewer system. This is also known as “Source Control,” “Industrial Pretreatment Inspection,” “IPP,” and “Industrial Waste Inspection.” • Plant Maintenance – This vocation deals with the maintenance and repair of wastewater treatment plants. Electrical/Instrumentation (EIT) and Mechanical Technology (MT) are the two specialties within this career. The EIT deals with the maintenance and repair of wastewater treatment plant electrical and instrumentation systems while the MT focuses on mechanical systems such as pumps and motors. • Industrial Waste Treatment Plant Operator – This type of operator works at wastewater treatment plants in private industrial facilities. • Biosolids Land Application Management – Biosolids are the inert biological materials (sludge) resulting from the wastewater treatment process. This vocation focuses on the management of these wastes. Most of the careers within the water and wastewater industries will require some type of certification. However, there are other specialty areas such as engineering and accounting that may require a specific degree. Throughout this course and program you will be exposed to a variety of career choices. Find the one(s) that you are interested in and pursue that discipline.

textbooks/workforce/Water_Systems_Technology/Water_120%3A_Introduction_to_Water_Systems_Technology/1.02%3A_Operator_Certification_and_Regulations.txt

Finding a job is dependent on a number of factors. Timing, current economic conditions, work skills, and more all play a part in trying to land a job. However, with a little bit of discipline and effort, finding a job is not too difficult. Although finding a “job” might not be too difficult, finding a career can be. What is the difference between a “job” and a “career”? A “job” for discussion purposes in this chapter is a place of employment that may or may not be full-time and will probably not lead to multiple years of employment in the same industry. That is not to say that someone cannot turn a “job” into a successful long lasting place of employment. It is just to distinguish between some place to work and a career in a specific industry. In this chapter, a career refers to a place of employment in a similar industry for many years—a career in the “water” industry. There are some industries that will flourish at times and then feel the downward effects of a slowing economy. For example, a career in the aerospace industry usually reaps the benefits from defense contracts but can also see a significant hit when the government decides to implement cuts in the defense budget. Although the “Tech” industry saw tremendous financial gains during the “dot com” boom of the late 1990s, there was a hit to that industry after the turn of the century. In addition, when the housing market crashed in 2008, many home builders and the construction industry saw profits plummet along with high levels of unemployment. All of these examples can be profitable and long lasting careers but they are also susceptible to economic uncertainty. Water and wastewater industries are a little different. This is not to say there are never layoffs or periods of economic challenges in these industries. However, people will always need a safe and reliable supply of drinking water and people will always create wastewater. Therefore, water utilities in general are very sustainable and recession proof industries. The water and wastewater industries will be referred to collectively as “water industry” throughout the text. Within each industry, there are multiple layers of careers from office functions to field construction workers. Some of these positions require specific job training and expertise while others might only require a high school diploma. The careers discussed in this text will fall under water distribution, water treatment, and wastewater treatment. Within each of these industries, distribution and treatment operators will be the main focus. A general understanding of distribution and treatment should be explained first. Water that is delivered to millions of people throughout the United States is transported through an array of aqueducts, storage reservoirs, large and small diameter pipes, treatment plants, pumps, valves, meters, and various appurtenances before it arrives at the customer’s faucet. In California, most of the water treated for domestic use moves through the State Water Project, Los Angeles Aqueduct, or the Colorado River Aqueduct. These large water conveyance systems are owned and operated by a variety of state and local agencies. For example, the State Water Project (SWP) is managed by the California Department of Water Resources (DWR). DWR manages the movement of water from an area just north of Sacramento down into Southern California. They employ hundreds of people who have the responsibility of delivering water to SWP contractors. There are twenty-seven member agencies including the local Santa Clarita Valley Water Agency and Metropolitan Water District. Much of the water we use for domestic purposes requires some type of treatment. There are dozens of treatment plants throughout the state and thousands throughout the country. These treatment plants rely on a network of sophisticated treatment process to provide safe and reliable drinking water to millions of people. Operating these treatment plants require highly trained and certified treatment operators, engineers, maintenance workers, managers, and office staff to keep the treatment process running effectively and efficiently. Once treated water leaves a treatment plant, it must move through a network of pipes, pumps, storage structures, and appurtenances before it reaches each customer. This is where water distribution systems step in. Water distributors are typically referred to as water purveyors or water retailers. A water purveyor might have as few as a couple employees or as many as hundreds to thousands. Field distribution operators are trained professionals and are required to be certified. Once the water has been used by customers, it ends up in either a storm drain, which predominately is left untreated as it makes its way to the ocean, or it ends up in a sanitary sewer system and is treated through a Water Reclamation Plant (WRP), Publically Owned Treatment Works (POTW), or a Wastewater Treatment Plant (WTP). WTP will be used in this text to collectively refer to all wastewater (sewer) treatment facilities. For all practical purposes, these are all similar facilities where wastewater (sewer water) is treated before being discharged. In addition, WTPs will have a network of piping leaving home and businesses to the WTP. Water Industry Careers Water industry employees are responsible to provide customers with safe and reliable drinking water and to safely treat wastewater to further protect human life and the environment. Safe water means it must comply with both state and federal drinking water regulations (discussed later in this text). Reliable water means that when a customer turns on their faucet water flows out. People tend to take things like electricity and water for granted. We flip a switch and the light goes on. We turn a faucet and water comes out. It is not until these resources are interrupted people get concerned and sometimes upset. There are hundreds of drinking water treatment plants throughout the U.S. These treatment plants have the responsibility to treat surface water to certain standards making it safe for human consumption. There are a variety of highly skilled positions within a treatment plant and staff responsibilities can range from operator to laboratory technician, from administrative assistant to water resource engineer. The distribution of water is an unseen necessity by millions of people throughout the world. There are over 18 billion miles of distribution piping throughout the U.S and over 50,000 community water systems. All of these drinking water systems require people to operate and run them. There are thousands of employment opportunities available throughout the U.S. However, operating a distribution system is a complex operation requiring trained personnel in a variety of job functions. Water purveyors can have different sources of supply including surface water, purchased water, groundwater, and recycled water. They can have few customers or thousands, a handful of employees or hundreds, but all of them will have similar functions. Making sure wastewater is properly treated is important for human and animal safety as well as for protecting the environment. WTP operators are responsible for making sure sewer flows coming into the plant are adequate for treatment purposes and must respond to any and all releases should they occur. Solids that are removed during the wastewater treatment process must also be properly handled and disposed. Although there are many unique and specialized job functions within a utility that require certification, there are also a number of “common” job opportunities as well. Most utilities will have staff positions that are similar to many other industries such as customer service, office management, accounting, etc. While some of the terminology might be different, many of these jobs will not require specific water related training. The previous paragraphs briefly introduced the areas of drinking water distribution and treatment and wastewater treatment. The remaining pages of this chapter will look at specific career opportunities in the water industry and how someone should go about applying for these jobs. The Office Staff Most offices are staffed with accounting, financial, human resource, billing, and customer service departments. Depending on the size of the organization these departments can be interrelated while other times there can be a number of employees staffing each department. Los Angeles Department of Water and Power (LADWP) for example staffs over 8,500 employees serving a total population of greater than one million. Approximately half of this staff is responsible for the water side while the other half is responsible for the electric side of the utility. Although there might be some overlap between the human resource and administration functions, there will still be staff that provide office and field related services to their respective areas. Typically, in larger organizations there will be multiple employees in each department providing specific support needs and functions. While in smaller organizations, certain functions might be covered by the same staff person. For example, sometimes billing and customer service functions might fall under a Customer Service Department and financial, accounting, and human resources might be under an umbrella such as an Administration Department. Regardless of department titles, all utilities must provide similar services, such as creating and mailing water bills, collecting money from customers, answering phone calls, responding to customer questions and complaints, ordering supplies, paying bills, providing salaries and services to employees as well as other vital job tasks. Although some operational staff spend much of their time in the office, we will consider them “operational” employees and list them under “Field Staff.” For the purpose of this text let’s look at a smaller sized utility as an example. Below is an organizational chart for the office staff of fictitious XYZ Water Department: The above chart represents a medium sized water utility with eleven (11) office employees. Remember, this is just an example and may not reflect what an agency looks like exactly. Some utilities are very large and have hundreds of employees and are usually separated into multiple departments, while other utilities can be quite small and one employee might perform multiple jobs/tasks. Let’s analyze the above example and discuss what some of the general functions might look like for each position and department. The next several paragraphs are some typical examples of what each job might entail. Remember, these are just examples to get you familiar with the industry as a whole and may not represent a specific job that you can apply for in the future. • General Manager – The General Manager (GM) is typically the position at the top of a water utility organization. However, in a privately (investor) owned utility, the title of the person at the top of the organizational chart would be referred to as the President. Regardless of the exact title, a President and General Manager have similar job functions. The GM oversees the daily operations of the entire organization. This oversight is not usually direct, which means that the GM does not typically discuss day-to-day operations with the staff on a daily basis. They might get updates through meetings or from managers. Although they may not be involved in the day-to-day operations, they are ultimately responsible for all aspects of the utility. In public agencies, they usually report to a governing board of directors, city council, water commission or some other entity that is either elected or appointed. In private (investor owned) water utilities, they would report to shareholders, which would be equivalent to a board of directors. The primary responsibility of a General Manager is to manage upper level staff, sources of water supply, budgeting, provide support to staff, and create meaningful and efficient policies for the governing body to review and adopt. General Managers are usually contracted employees and are hired by the governing boards whereas Presidents are typically hired employees and do not have any guaranteed contract. Education and background for people seeking a GM type of position would be in the areas of engineering, science, and public administration. Sometimes a General Manager will also serve as the “Chief Engineer” of an agency. They may also have an advanced degree in a science-related field. Regardless of their background and education, this position would have similar responsibilities in all three (3) types of water related industries • Administration, Finance, and Human Resource Manager - This position can have various titles, but the function is to manage and oversee the day-to-day operations within the office. In a private utility, this position is typically referred to as a Vice President. They usually have multiple direct reports and in smaller utilities it might be one (1) person handling all human resource related tasks as well as administration and financial related responsibilities. Typical functions include preparing documents such as policy, safety, emergency response, and employee manuals. These types of managers keep the office organized and running efficiently. In larger organizations there may be separate positions for Administration, Finance, and Human Resource responsibilities with a staff reporting to each manager. These types of positions typically require a degree in business and or public administration. • Customer Service Managers and Departments - Customer Service staffs are the “face” of the organization. They deal directly with the public on a daily basis. They make sure that water meter reads are accurate and input correctly into the billing system. They issue water bills, accept payments, send reminders to late paying customers, and handle any issue a customer has when they call or come into the office. Many interactions with customers are related to complaints of incorrect billings, high usage, and other customer account related inquiries. However, other times customers will call to complain about operational problems such as leaks, low pressure, no water, poor quality, etc. Sometimes, customer service staff can resolve these types of complaints by asking a few questions and responding the customer’s concern. Other times, work orders are generated and forwarded on to the appropriate operations department. As with most managerial positions, a degree is usually required. However, sometimes organizations will promote long time employees that have shown a dedication to the agency and a willingness and ability to learn on the job. • Accounting Managers and Departments - The flow of money moves through accounting departments. The primary revenue source for most water utilities is through water usage payments. However, some utilities collect taxes, rents, and various other sources of revenue. Just as money comes into a utility it goes out as well. Salaries, benefits, insurance are some of the more costly expenses that utilities must balance. In addition, office supplies are purchased and an inventory of parts and materials are maintained so operational staff can make repairs and replacements as they present themselves. Consulting is also a large part of a utilities expense. Engineering consultants, attorneys, and specialized contractors are all a part of a utilities operation. Every utility has a warehouse to store and maintain a variety of inventory items. Although operational staffs are using the material in inventory, it is the responsibility of the accounting department to reconcile the “ins and outs” of each item and the associated costs. Typically accounting managers will be Certified Public Accounts (CPA) and have a business-related degree. Typically, all of the above mentioned managers and departments will have support staff. The support staff will process paperwork, deal directly with customers, and provide a variety of support related responsibilities. These employees will need to be proficient with computers and be able to write memos, input data into spreadsheets, and use specialized software to handle billing, inventory, purchasing orders, and other various tasks. Many of these positions are entry level and will not require a degree. The Field Staff Every utility has a staff that predominately works in the office and a staff that occupies most of their time outside (or in the “field”). As explained earlier in this text some of the operational managers and supervisors spend most of their time in the office, but will be discussed as “field staff” in this text. Field staff and operational duties range from reading meters, fixing leaks, collecting water samples, installing services and pipelines to responding to complaints, maintaining facilities and appurtenances. Many utilities are separated into several departments such as Maintenance, Construction, Water Quality, and Customer Service while others might divide departments even further. For instance there might be a department for valve operators, leak repairs, electricians, etc. Regardless of the structure of a utilities operation, they all have the same basic functions of getting water from the source to the customer in a reliable and safe manner. Below is a generic organizational chart for a medium sized utility: In this example, there would be crews under each Supervisor/Superintendent. Sometimes the Superintendent is a step up and oversees the various departments. Crews can be large or small. For instance, construction and maintenance crews tend to be larger than water quality technicians, primarily because there are more construction and maintenance related activities compared to collecting water quality samples. Let’s take a look at common tasks and responsibilities of the various operation positions. • General Manager - As previously mentioned, the GM (and President) is responsible for the entire organization. In addition to the various administrative and personnel related functions, a GM quite often gets involved in planning and design of the vast array of different facilities. Many times a GM will have an engineering degree, water quality experience, or some science and business related background. • Operations Manager - This position is responsible for the overall day-to-day operations of a utility. Although Operations Managers spend most of their time in an office, they meet regularly with the various operations supervisor getting updated and briefed on daily activities. An operation manager will typically be responsible for the operations budget and tracks expenses incurred for various construction and maintenance related projects. Many times an operations manager and GM work closely together to strategically plan system improvement projects and future development. This type of position is typically the equivalent to the Vice President position of a private utility. Most Operations Managers will have some type of four (4) year degree in engineering, science, or sometimes business. • Superintendent - Superintendents are usually the eyes and ears of all field activities. They are typically field-based employees that spend some of their time in an office behind a desk. They coordinate and communicate most of the day-to-day activities and assist the various departments including, but not limited to construction, maintenance, water quality, and field customer service. Typically the Superintendent has many years of experience in the field as an operator or some other field position and works their way up to this position. Usually this position would not require a four (4) year college degree. However, there would be certification requirements and more than likely a D5 certification would be required. • Construction – Not every utility will have a construction crew(s). Sometimes this type of work is contracted out to independent private construction companies. Either way, construction can be a large part of the responsibilities for water utilities. Construction activities range from the installation of water mains and services to the repair of leaks. Crews may build facilities such as pump stations and they may provide services for new infrastructure installation and capital improvement replacements. A supervisor or foreman typically leads this group and there usually is at least one heavy equipment operator. There are also certification requirements for positions within construction departments, including the required Division of Drinking Water (DDW) certifications and Class A licenses for heavy equipment operators. Typically very little experience is required for entry level construction jobs. However, positions within construction departments can be the most demanding physically and can often require employees to work nights and weekends. • Maintenance – In addition to the installation and repair of facilities and appurtenances, maintenance of the systems is an important part of every utility. Pumps and motors need routine inspection and adjustments. Valves need to be routinely operated. Fire hydrants need to be flushed and painted periodically. There are also many different types of routine maintenance of buildings and the property facilities are built on. Just as you might maintain a car or a home, water facilities and structures need to be maintained. Typically there is a supervisor for maintenance crews. The supervisor would be the person in charge of scheduling and assigning the maintenance work. There might be various types of schedules with varying frequency. For example, valves might be on an annual schedule and motors and pumps might be on a semi-annual schedule. Regardless of the schedule, all maintenance activities should be well documented and tracked. • Water Quality – All water utilities will have some type of water quality department. In small organizations it might be one person who handles these responsibilities. In larger utilities, there might be a department with multiple crews. There are minimum sampling, monitoring, and reporting requirements all utilities must abide by. A water quality specialist or technician is usually responsible for these duties. Sometimes agencies will have field technicians and an office water quality position. While other times field and office duties will be the responsibility of the same person or group of people. For example, a technician might be the person collecting the samples and a specialist might be the person preparing the sample bottles, interpreting the sample results, and preparing the reports. Regardless who is responsible for what task, a water quality professional will need to be a certified operator and sometimes will need a science-related degree. • Engineering and Geographic Information Systems (GIS) - There are many engineers in the water industry. Treatment plants, pumping facilities, storage tanks, and many other types of facilities need to be designed and constructed. On-staff engineers or hired engineering consultants are the ones responsible for designing and mapping the systems. After a facility, piping infrastructure, or some part of a system is designed and constructed there are “mark-up” plans that come back to the engineering departments. These plans are called “as-built” drawings. They are drawings “as they were built”. Sometimes the construction crew will make field modifications for various reasons. They will then create as-built drawings so the engineers can update their plans and provide the staff will accurate complete drawings. Many utilities employ GIS personnel. GIS is another mapping function and includes facility data and information in a geographic database. For example, pipelines have information associated with them such as, diameter, length, material, installation date, etc. This data can be geographically coded with the pipe and retrieved at the click of a button. Often times field operators will have “paper” maps with minimal information written on them. Sometimes they will need to return to the office or contact someone to retrieve detailed information. Technology is now allowing field crews to carry tablets or laptops in the field enabling them to access GIS data immediately. Engineering and GIS employees will almost always require a four (4) year degree and quite often advanced degrees and special licenses and certifications. These examples are by no means an exhaustive list of career paths and job opportunities in the water industry. Utilities are unique in size and in their hiring processes. As mentioned above, each department can have few or many employees. For example, there might be a Water Quality Manager with three (3) Water Quality Supervisors each having several Water Quality Technicians reporting to them. In very small utilities one person might make up the entire department. The size of the utility will have an effect on the hiring process and the employment opportunity potential. Large public utilities can have hundreds of people applying for one position and typically have a test that all the applicants must complete. This “test” is used to screen out individuals and quite often only the top few scores are called back for an interview. Sometimes you will be interviewing in front of a panel of people, while in small private agencies it might be a one-on-one interview. Regardless of the process a worthy applicant needs to be well prepared. Taking water related coursework, becoming certified operators, and gaining experience will all help to increase the opportunity for gaining employment. Stay focused, work hard, and don’t become discouraged. Landing a job that turns into a career in the water industry is a real possibility and very rewarding.

textbooks/workforce/Water_Systems_Technology/Water_120%3A_Introduction_to_Water_Systems_Technology/1.03%3A_Career_Opportunities_In_the_Water_Industry.txt

Cover Letters, Resumes, and Applications Looking for a job can be a very stressful task. No one likes rejection and many times rejection is part of the job-seeking process. The best time to look for a job is when you are currently employed. This way a rejection letter from a prospective employer may not “sting” as much since you are currently working. However, most of us are not that fortunate to be able to search for a new job while we are currently employed. Many times we are forced into a situation where we are looking for work because we have been laid-off, or the business has closed, or perhaps we are looking for a career change. No matter what the reasons are requiring us to search for new employment, a cover letter, resume, and interview will play an important role in helping us land that ideal job. Taking time to prepare a thoughtful cover letter and a complete resume are extremely valuable tools in presenting your skills and experience to employers. With the help of the Internet, there is really no reason to not have a well-written cover letter and resume. Below are just a couple of the resources you can find online to assist you with the development of cover letter and resume. • About.com Job Searching http://jobsearch.about.com/od/coverletters/a/aa030401a.htm • Yale Undergraduate Career Service http://ucs.yalecollege.yale.edu/content/cover-letters Cover Letter What is a Cover Letter and why is it so important? Is a cover letter needed when submitting a resume and applying for a job? What constitutes a good cover letter? Is there a difference between a “good” cover letter and a “great” cover letter? Many times people overlook the importance of a cover letter. Much time is spent on crafting and developing a complete resume; oftentimes, the cover letter is an afterthought. According to www.careerbuilder.com, neglecting a cover letter is a “big mistake.” A cover letter is your first shot at introducing yourself to a prospective employer and making a good or even great first impression can be the difference between landing an interview and receiving the dreaded, “thank you for your interest, but we have selected another candidate.” Cover letters provide you the opportunity to cover everything that cannot be expressed in a resume and begin the “selling” process of your abilities. They also provide the opportunity to address a specific person within an organization making your application for a job more personable. It is advised to find the name of the person you are sending your cover letter and resume to and address it to them specifically. Doing a little research in the organization you are applying with can go a long way. To the person reviewing and filtering applicants it looks better to see their name on the cover letter as opposed to “To whom it may concern.” What makes a cover letter? In general, cover letter should be well written, concise, to the point, and specific to the job you are seeking. • Well written – No one likes to read a cover letter filled with spelling and grammar mistakes. Sometimes simple words like “form” and “from” can be accidentally used because they are both spelled correctly and are just out of context. Long run-on sentences, too many paragraphs, and improperly used punctuation can make a cover letter a struggle to read and can be the difference between landing an interview or having your resume passed over. Make sure you proofread it multiple times. Sometimes reading out loud can help identify mistakes. It also doesn’t hurt to have a friend, co-worker, or family member review it for you. Sometimes a second or third set of eyes can pick up things that you might miss. • Concise – Being concise means writing clearly and efficiently. Do not add a bunch of words just to fill space. Identify what you want to say and draft an outline of the key points. Many times you will be applying for a job with dozens of other candidates and the person receiving and reading cover letters may not have the time to read through paragraphs of writing. Typically a well-written cover letter should contain: • An introduction of who you are and why you are writing the company. A few sentences identifying yourself and why you are applying for this specific job. • A paragraph summarizing your qualifications and experience, without rewriting your resume in the cover letter. Sometimes a few bullet points listing your strong points works or a short paragraph of your highest level abilities and experiences. • A concluding paragraph of why you would be a good fit for the organization. Do some research on the organization and try and figure out the culture of the company. Each business has a unique culture. Being able to identify the culture and describing how you will fit in this culture can go a long way. Finishing off with a sentence such as, “I look forward to speaking with you in person to discuss my qualifications and experience” is a nice closing. There is a fine line between being concise and not providing enough information to peek the interest of the organization. There are plenty of sample cover letters on the Internet. Be sure to do your research on crafting and writing a cover letter and also on the company you are applying with. • Specific to the job you are applying for – A generic cover letter and resume indicate a sign of laziness. Much of your cover letter can be “generic.” It can have the same heading and components of the introduction and closing can be similar. However, tailoring your cover letter to the specific job you are applying for shows the organization that you have at least put some thought into this application process. Here is an example of a cover letter introduction: Please accept this cover letter and resume as serious interest in the position available with your company. I think I will be a good fit. Or Please accept this cover letter and resume as serious interest in the position of Water Quality Specialist with XYZ Water District. I believe my qualifications and education will set me apart from others applying for this position. Identifying the position and the agency shows that you have taken time to write the cover letter. Lastly we will look at formatting. Organizing and formatting your cover letter is also very important. Take your time writing contact information on the top of your cover letter and resume. It should include your name, address, phone number, and email address. It shouldn’t be too fancy but it should also stand out so that it is recognizable at a glance. Here is an example: John Doe 1234 Water Way, Spring Town, USA 111-222-3333 [email protected] It doesn’t have to be fancy, it just needs to stand out and be easy for the agency to identify whose resume and cover letter they are looking at. You should provide a phone number that you typically answer or check regularly. You should also use an appropriate email address. Many times people have what they consider to be funny or clever email addresses. If you are one of these people, then create an email account specifically for looking for a job. A prospective employer is not interested in contacting “[email protected]” or “[email protected]” for an interview. A simple first initial, last name or first name, last initial is an appropriate email address to list on all your contact information when searching for employment. Lastly regarding format, make your cover letter look clean and professional and be sure to personally sign it. If you are submitting your information through email or online, print the document, sign it, scan it, and then submit it. Resume Your resume should contain a summary of your work and education experiences. It should list each employer that you have worked for and the position you held with that organization. It should list your educational background and any related research work you may have participated in. There are various types of resumes and there is a ton of reference information that can be found online. Do your research and find the type of resume that fits best and enables you to express your experiences and education. In this section we will focus on three main resume types: Chronological, Functional, and Targeted (www.jobsearch.about.com). Don’t worry if you do not have any work experience. Everyone has to have a “first” job. In situations where you do not have any work experience state this in your cover letter. Write a couple short sentences as to why you do not have any work experience and something like, “I am eager to start a career and gain on the job experiences.” Sometimes applicants have work experience, but not directly related to the job they are applying. Perhaps you have experience in aerospace or computers or something completely different. In these instances, be creative. There are a couple of general rules regarding resume content. Typically you should include the following information: • Objective – a one to two sentence statement about your goal. What is it that you seek to accomplish? “I am seeking a career in the water industry to further my knowledge in water technology and to increase my commitment to serving the public by helping to provide a vital resource.” • Summary of Qualifications – a summary of qualifications is not always necessary in a resume, especially if you provide this type of summary in your cover letter. However, if you have some specific skills that are required by the job you are applying for, it can’t hurt. • Work Experience – listing your prior work experience is very important. It shows your prospective employer that you are employable and that you have a track record of good standing. Chronological Resume This type of resume shows your work experience and educational experience in chronological order, starting with your most recent experience. This is probably the most common type of resume and is often preferred by employers. It is an easy way for an employer to see what you have done and the various times you have done it. This type of resume can be problematic if you have large gaps in employment. Large gaps in employment can be a red flag for employers. Sometimes there are perfectly acceptable reasons for gaps in employment but you don’t want to alarm a prospective employer before you have the chance to explain. If you do have gaps in employment and you have specific reasons for the gaps, it might be a good idea to discuss those briefly in your cover letter. For example, if you decided to stop working to go back to school or maybe you stopped working to have children. These are understandable reasons for having some gaps in employment. Regardless of the reason, you want to be able to explain it during an interview and you do not want your resume to be passed over without having the ability to explain yourself. There are various thoughts on what you should list first, your work experiences or your educational experiences. The best answer is probably to lead with whatever is stronger. For example, you might be a recent college graduate with very little work experience. In this situation, you may want to list your education first. Functional Resume This type of resume focuses on skills and experience. When there are be gaps in your employment history, it is sometimes better to focus on the specific skills and experiences you might have for the job you are applying for. This type of resume is very common for people who are changing careers. For example, you may have been an auto mechanic for 15 years and decided to change career paths. You took some time off to study the industry of water systems technology. Several years have passed without any employment history and you are now applying for a maintenance mechanic position with a water agency. Instead of listing your employment history with a gap while you were in school, focus on your experiences as a mechanic and relate those to the position of maintenance mechanic. During the interview, if you are asked about the gap in employment you can explain that at the time it was your desire to change careers and go back to school. Combination Resume As the name implies, a combination resume includes both experience and employment history. You can focus on the specific skills and experiences related to the job you are applying for and list the employment history as a reference for the employer. This is a very common approach when applicants have a combination of experience and work history but neither one is strong enough on its own merit. There are many examples of the various types of resumes online. It is strongly recommended that you research the type and style that would fit best. Applications It may seem fairly straight forward how and why you should complete an application but many times the application is the crucial document that will either bring you to the next level or result in the dreaded, “Thank you for your interest in employment with ABC Water Company but you have not met the minimum requirements for the position.” Quite often, especially when there are hundreds of applicants, there is an application screening process and the simplest of errors on the application can result in being disqualified. Or, sometimes in smaller agencies, your application can be put on the bottom of the list based on sloppiness, misspellings, missing information, etc. Completeness and neatness are two key elements to a successful application. Many job descriptions will state minimum requirements to help filter out what can at times be hundreds of applicants. Maybe a certain certification level is required or perhaps a specific degree? Depending on the agency you are applying for employment with, you may not need ALL the minimum requirements at the time of applying. While others will disqualify your application if you do not meet everything stated in the description. Below are a couple job description requirements and what is recommended for an acceptable application submission: Meter Reader - Minimum Requirements Associate of Science Degree from a two-year college is required. One year general work experience and Water Distribution Operator Grade D1 certificate from Division of Drinking Water preferred. Let’s say that you will receive your AS in one month and you meet the minimum “general work experience” requirement. Remember, the D1 is not a requirement. Some agencies may look at your application and accept the fact that your official graduation date is in one month and allow your application to be processed for an interview. Other agencies may disqualify you because you will not be in possession of the degree at the time the application is due. While looking at this job requirement scenario, the questions below may have come to mind: What if you don’t have an AS degree but you have a D1 certificate? What if you have both an AS degree and a D1 certificate? They are excellent questions and cannot be fully answered because each water utility will have different requirements and standards for their application review process. However, your chances of progressing through the application process are probably better if you meet the minimum and preferred requirements. Water Quality Specialist - Minimum Requirements This position requires a 2-year degree in Biology, Chemistry or related field and 2 years experience in a water laboratory environment. A Water Treatment Operator T2 certificate is required. The requirements for this job are a little more stringent and most agencies would probably disqualify you if you did not meet them. However, if you have completed and passed the T2 exam and you are just waiting for your certificate, you might be allowed to progress through the application process. Regardless of your skills, experience, education, and background, you should not be discouraged from applying for jobs even if you think you are not qualified. Each agency is different and there are variety of circumstances. Just make sure you are well prepared and provide neat and complete cover letters, resumes, and applications before you apply. Something not discussed in this chapter or text is the interviewing process. Interviewing is as much a skill as an art. The following are simple tips to help you prepare for an interview. However, the best preparation is practice. Try video recording yourself or practice in a mirror. You can also ask a friend or family member to ask you specific questions in a mock interview. Interview Tips 1. Dress for Success but don’t over dress for the job. First impressions mean a lot. If you walk into an interview wearing jeans and a t-shirt, the first impression might disqualify you before you even say a word. Likewise, if you are applying for a construction related position, it might not make sense to show up at the interview in a suit. Nice slacks and a button down shirt or blouse should be acceptable for most field related water positions. You can add a jacket or blazer if you wish. It is important to not seem too overdressed for a field position but you don't want to seem underdressed either. Slacks and a button down shirt or blouse is a good compromise for a field position. And, of course, your clothes should be clean and unwrinkled. 2. Improve you interview technique. Practice is the best way to improve. Getting caught off guard with a certain question might be the difference between you and the next person. However, you should also not be afraid to say you don’t know or ask if they could repeat the question. Try to be relaxed and take time to think before answering. 3. Take time to say thank you. Always be polite and thank the interviewers. It is also recommended to write a thank you letter after the interview. 4. Networking is always helpful. Knowing someone in the organization or if you know common acquaintances can always help your chances to separate you from the next person. 5. Research the company. Researching the company is not only helpful with preparation of your cover letter and resume, it also helps during the interview process.

textbooks/workforce/Water_Systems_Technology/Water_120%3A_Introduction_to_Water_Systems_Technology/1.04%3A_Career_Opportunities.txt

One of the most important responsibilities of a water utility is to provide SAFE drinking water. “Safe” can be a confusing word for water utility customers. At times the safety of drinking water is confused with its aesthetic qualities such as taste, odor, and color. Sure, no one wants to drink water that is discolored, has an odor, or tastes bad. However, most of the time the water is safe to drink regardless of how it looks, tastes, and smells. Now, this doesn’t mean that water utilities are supplying customers with aesthetically unpleasing water. It simply means that often the safety of the water has little to do with its aesthetic quality. This is why there are both PRIMARY and SECONDARY drinking water regulations. Primary standards deal with health-related issues while secondary standards focus on aesthetic qualities of the water supply. Although water utilities strive to supply the best water possible, there are times when the water might be unpleasant from aesthetic characteristics. This chapter will discuss both primary and secondary water quality regulations, providing examples of both, as well as a discussion of various job opportunities within this discipline of the water utility industry. Almost everyone is concerned with the quality of their water. It is typically the top complaint from customers, with the exception of high water bills. Since tap water is usually colorless, odorless, and, for the most part, tasteless, as soon as something changes, customers want to know why. Water quality is also a top concern of water professionals. Water quality professionals are responsible for the treatment, disinfection, testing, and compliance of the water served to their customers. Every year water utilities collect thousands of water samples and have them analyzed by laboratories to ensure compliance with water quality regulations. In addition to collecting samples, water utility operators conduct preventive maintenance, routinely inspect facilities, and respond to customer complaints to prevent and/or correct any water quality problems. Water Quality Regulations Current drinking water regulations are very complex and include many different requirements. This following text is a brief historical overview. President Gerald Ford signed the Safe Drinking Water Act (SDWA) in 1974 under growing pressure from newspaper articles, documentaries, and the general public’s skepticism that drinking water might not be safe. The Environmental Protection Agency (EPA) conducted a national reconnaissance study to assess the concentrations, sources, and potential danger of certain contaminants in municipal drinking water supplies. In 1977, the national safe drinking water standards went into effect across the country. These standards included microbiological contaminants, ten (10) inorganic chemicals, six (6) organic pesticides, turbidity (or cloudiness), and radiological contamination. Among other things, the regulations also included a provision for the States to assume primary enforcement responsibility. Since the enactment of the Federal Safe Drinking Water Act, there have been two (2) amendments. In 1986, the first amendment was passed. Some of the new requirements with this amendment increased the number of regulated contaminants, required certain filtration processes for surface water supplies, added disinfection requirements for some groundwater systems, and prohibited the use of lead solders, flux, and pipes in public water systems. Ten (10) years later the 1996 amendment was passed. This added a provision in the SDWA referred to as the Unregulated Contaminant Monitoring Rule (UCMR). The UCMR requires the EPA to provide a list of potential contaminants every five (5) years to water utilities so that their drinking water supplies can be analyzed. The EPA will then use this data to prepare future water quality standards. The amendment also created distribution and treatment operator certification requirements and a funding system for states needing financial help to comply with drinking water quality regulations. This funding is referred to as the Safe Drinking Water Revolving Loan Fund. It is important to note that although there are federal drinking water regulations, many states have their own drinking water standards. In California, the regulatory agency is the Division of Drinking Water (DDW) under the State Water Resources Control Board (SWRCB). The DDW is responsible for enforcing the California Safe Drinking Water Act (CSDWA). Many states create their own regulatory agencies to help enforce the Safe Drinking Water Act. Drinking water quality standards can be broken into two main categories: Primary Drinking Water Standards and Secondary Drinking Water Standards. Each set of standards has a list of contaminants that must be monitored by municipal water utilities and they must be below levels considered safe. These safe levels are referred to in the regulations as Maximum Contaminant Levels (MCL). Each constituent has a separate MCL that cannot be exceeded in the water supply or else some action must be taken. An action can be as stringent as taking the source of supply (i.e., groundwater well) immediately out of service. Or it may increase the amount of sampling requirements for a particular constituent. Exceeding an MCL may also require some type of notification to customers. The goal is to protect the public from unsafe levels of potential contaminants in water supplies. Drinking water quality regulations are not the only water quality regulations water utilities must comply with. There are many water quality regulations protecting the environment. These regulations are part of the Clean Water Act (CWA). The CWA regulates and permits the sampling and monitoring of discharges to “navigable waters of the United States.” Navigable waters are defined by the US Army Corps of Engineers as waters that are subjected to the ebb and flow of tide, and those inland waters that are presently used, or have been used in the past or may be susceptible to use in interstate or foreign commerce. This definition can be interpreted by water utility operators as any body of water wet or dry that discharges can flow into. Common water utility discharges include, but are not limited to flows from: • Fire hydrant and dead-end flushing • Water main flushing • Meter testing • Water leaks • Storage tank overflows • Water sample collection Although water utilities are required to discharge water for a number of these activities, they must still comply with the CWA and the various State and Local regulatory agencies responsible for implementing the requirements set forth in the CWA. Much of the requirements involve preventing chlorinated water from entering a water body or preventing debris from gutters and storm drains being washed into a water body. Primary Drinking Water Standards Primary Drinking Water Standards are for contaminants that pose a health threat when detected in water supplies above an MCL. In order to establish an MCL, the EPA will take into consideration several different factors. They will examine the prevalence and exposure of the contaminant in the environment and in water specifically. A contaminant that isn’t found in water supplies often would find a place low on the EPA priority list. However, a contaminant that is widespread would be at the top of the list. The EPA also looks at health effects. If it is wide spread contaminant but has little to no known health effects to humans then an MCL would not be very probable. However, if the contaminant is toxic or a known carcinogen then an MCL would be very likely. Another consideration is in regards to the analytical methodology. There has to be a statistically reproducible laboratory analytical method in order for the EPA to consider an MCL. If a laboratory cannot detect the contaminant readily and statistically accurate, then having an MCL would be very difficult. Lastly, an economic evaluation is completed. Typically the cost benefit analysis looks at all the previously reviewed material. Millions of dollars a year are spent by water utilities in efforts to comply with Primary Drinking Water Standards. It is one of the most important responsibilities of water professionals. There are a host of treatment technologies that are used to inactivate or remove contaminants from water. Thousands of samples are collected and analyzed to determine the level of each contaminant. Reports are prepared and filed with public health agencies to demonstrate compliance with the regulations. Primary Drinking Water Standards are commonly broken up into four (4) main categories: 1. Bacteriological 2. Inorganic Chemical 3. Organic Chemical 4. Radiological Compounds There are multiple constituents within each broad category and it is the utility’s responsibility (with the assistance from the regulatory agencies) to understand the requirements for complying with these contaminants. Below is a brief description of each category, the predominant health effect associated with each, and various treatment methods. Bacteriological This group consists of not only bacteriological contamination, but also viruses, protozoa and various other microorganisms that pose a health threat. Most of the health effects associated with microbiological contamination in water are gastrointestinal. Symptoms include vomiting, diarrhea, headache, fever, etc. Many of the symptoms are similar to influenza. However, to various sub-populations, for example the very young or old or people with compromised immune systems, the health effects can be deadly. Because of the vast number of microorganisms and the difficulty and cost of trying to analyze all of them, an indicator organism group is used for analysis. This group is known as the total coliform group. Coliforms are a group of bacteria that indicate the presence or absence of disease causing microorganisms. The Total Coliform Rule (TCR) is a set of regulations that cover this wide range of contaminants. Although there are various treatment techniques for the removal and inactivation of microbiological contamination, disinfection is the most common method. Drinking water treatment facilities and distribution systems both use disinfectant chemicals (primarily chlorine) for maintaining the health and safety of drinking water from microorganisms. Inorganic Chemicals There are many different chemicals found in drinking water supplies that fall under this broad category. Fortunately most of them are naturally occurring and are considered safe. For example, minerals such as calcium and magnesium are commonly found in drinking water supplies. Although these may pose aesthetic problems for consumers (discussed later in this chapter), they pose no health effects. However, contaminants such as nitrate, arsenic, and chromium can also be found as naturally occurring elements in drinking water and these can pose health problems if ingested at levels above the MCL. In addition to being found naturally in the environment, these and many others are the result of some type of contamination. • Nitrate – The primary source of nitrate contamination is from some type of fecal contamination. Agricultural farms and leaking septic systems both contribute to nitrate contamination. The main health effect is related to infants six (6) months and younger. If nitrate is ingested at levels above the MCL by this sub-population, a condition known as metheglobinemia (Blue Baby Syndrome) can occur. This results in suffocation when nitrogen displaces oxygen in the bloodstream. • Arsenic – Arsenic has been used as a wood preservative resulting in contamination and is also naturally occurring. The primary health effect associated with drinking water containing arsenic at levels above the MCL are cancer-related. • Chromium – This chemical got its spotlight from the movie Erin Brockovich. An oxidized form of chromium known as “Chrome6” or hexavalent chromium was brought to everyone’s attention when Pacific Gas and Electronic was accused of contaminating the groundwater supply in Hinkley, California. This contaminant also causes cancer-related health effects. Inorganic chemicals are not commonly found in drinking water supplies above their respective MCL. However, if they are, there are several treatment techniques that can remove these and many other contaminants from the water supply, ion exchange being one of the most common. Organic Chemicals The most commonly found organic chemicals found in drinking water supplies fall under the category of VOCs. VOC stands for volatile organic compound and are present in drinking water typically from the result of some type of contamination. Some of the more common VOCs found in drinking water include: • Trichloroethylene (TCE) • Tetrachloroethylene (PCE) • Methyl Tertiary Butyl Ether (MTBE) These chemicals come from various sources including degreasing agents, dry cleaners, and fuel additives respectively. These are considered “volatile” because of their propensity to evaporate or sublimate from the liquid or solid form of the compound and enter the surrounding atmosphere. Therefore, one of the more common treatment techniques to remove VOCs from drinking water is granular activated carbon in combination with packed air towers. The primary health effect from drinking water containing VOCs at levels above the MCL is cancer. Radiological Compounds The primary source of radiological compounds in drinking water is from naturally occurring sources. Geologic formations can contain uranium, radium, strontium and other radiological compounds. In rare cases, radiological contamination can result from a nuclear facility accident. However, this is not very common. As with many drinking water contaminants the primary health effect is cancer-related. Common treatment for radionuclides is ion exchange. In addition to the treatment techniques previously mentioned, blending is a type of “treatment” technique that DDW may approve. However, blending is typically only approved for contaminants that do not pose an acute (immediate) health risk. The previous examples are not a complete list of potential contaminants in drinking water, nor is the information provided an exhaustive explanation. It is a glimpse into drinking water quality providing the reader a background overview. Secondary Drinking Water Standards Although Primary Drinking Water Standards are the most important regulations for water professionals, aesthetic quality is still a significant challenge and focus of drinking water providers. Making sure water is safe to drink is critical but if customers do not like the taste, odor, or color of the water they are likely to think that the water is unsafe and not fit for cooking and drinking. Therefore, it is important for water utilities to respond and take seriously all customer complaints, have a good preventive maintenance program, collect samples routinely and comply with all regulatory requirements. However, even the most diligent utilities can experience aesthetic water quality problems. Some aesthetic quality problems can be addressed by routine flushing and preventive maintenance programs, but some are the result of certain naturally occurring conditions and can only be removed through treatment and/or blending. With varying sources of supply, comes varying water quality. Aquifer formations made up of limestone would tend to have higher levels of calcium, while other geologic formations might contribute other minerals such as magnesium, sodium, and potassium to name a few. Therefore, the quality of water in Los Angeles can be completely different than the water quality in Phoenix. However, in the United States all water must meet the minimum federal and state drinking water standards. Common Aesthetic Issues with Drinking Water Although the United States has some of the safest drinking water supplies in the world, sometimes little effort is focused on the aesthetic qualities. A crystal clear glass of water may not be safe to drink because it can have harmful tasteless and colorless contaminants in it. At the same time, discolored water with a bad smell and taste can be perfectly safe to drink. Everyone wants safe water to drink but it is usually the aesthetic qualities that determine if we will drink the water. Many times when people are asked why they drink bottled water instead of tap water, their answer is usually “because it tastes” better. So why does some water look, taste, and smell bad? There are various things that can cause aesthetic issues with drinking water. The following scenarios provide just a few common issues facing water utilities. Please note that each scenario only reflects typical responses to common problems. They are meant as examples only. • Scenario 1 - A customer calls their local utility complaining of a slight yellow color to the water. What can cause this discoloration? What should the utility tell the customer? As mentioned previously, all water quality complaints should be treated with concern and taken seriously. A common first response from a water quality professional might be, “Is the discoloration coming from all the faucets in the home?” This simple question will help determine if the problem is coming from the customer’s internal plumbing system or if it is coming from the water being served by the utility. If the discoloration is coming from all faucets, then the next step would be to check the water coming into the home. Sometimes the utility will send someone out to investigate, while other times the homeowner can be asked to flow the water at the front hose bib to check for discoloration. Usually the answer from the customer is the discoloration is only coming from a certain faucet or area in the home. A common source of the discoloration is from older galvanized internal plumbing systems. Sometimes a bathtub or sink is not used very often and iron from the internal plumbing system can leach out and cause a brown/yellow discoloration. A common suggestion to the homeowner would be to run the faucet for a while until the discoloration clears up. • Scenario 2 - A customer calls complaining of cloudy water. Cloudiness or “milky” looking tap water is commonly entrapped air in the water. A test that water quality professionals ask the customer to try is to fill up a clear glass and set it on the counter. If it is air then the cloudiness will begin to clear from the bottom of the glass up. This is because the air bubbles will rise into the atmosphere. • Scenario 3 - Sometimes customers will call and complain about odors. Customers will often call saying their water smells like a “pool.” Chances are something has changed in the distribution system or with the disinfection process. Drinking water is commonly disinfected with chlorine or chloramines. The switch from one to the other can cause “pool” chlorine type of orders. Or if water usage demands in the system have changed these same odors can be present for a short period of time. No matter what the customer complaint is, all water professionals need to be honest, provide specific detail and help, and if they are ever uncertain of the solution to the customer’s concern, tell them they will need to investigate the issue and will provide them with a response as soon as possible. As you can see, drinking water quality regulatory compliance is a complex and detailed area of the drinking water industry. However, regulations are readily available and government regulators are typically very helpful and responsive to questions from utilities. Water professionals and regulators alike should have the same goal of providing the public with a safe and reliable supply of drinking water.

textbooks/workforce/Water_Systems_Technology/Water_120%3A_Introduction_to_Water_Systems_Technology/1.05%3A_Water_Quality.txt

Drinking water comes from a variety of different sources. As water makes its way through the hydrologic cycle, it comes back to land in the form of precipitation (rain, sleet, snow, etc.). Some of it is captured in lakes and rivers, while some of it percolates into the earth’s surface and becomes groundwater. Groundwater can be pumped back up through groundwater wells and surface water can be treated and delivered to customers. In order for water to continue to flow out of the faucet when it is turned on by customers, it requires a network of pipes, pumps, storage, and other components which make up a distribution system. The water distribution system is the focus of this chapter. We will identify how water enters, travels through, and leaves a distribution system. Some of the focal points for discussion are storage, pipes, pumps, and various appurtenances. Appurtenance is a general term used to describe things such as valves, fire hydrants, meters, among other things. There are various names which refer to a company which distributes water to customers. Some examples include, water retailer, water utility, water district, water agency, water purveyor, and water supplier. These terms may be used throughout this text with the understanding they all virtually mean the same thing. Sources of Supply Water 032 Water Supply is a full semester course covering the details of sources of water supply. For this course, we will touch on some of the general aspects of water supply. As mentioned in the introduction to this chapter, most water supplies come from either surface water sources or groundwater sources. All surface water must go through treatment before it can be used for domestic purposes. A water supplier operating a distribution system must either operate their own drinking water treatment plant or purchase water from a drinking water treatment plant if they intend to use surface water as a source of supply. Let’s look at a couple of local Southern California examples. The Los Angeles Department of Water and Power (LADWP) is one of the largest water suppliers in the country. They are an example of a utility which owns and operates a drinking water treatment plant as well as distributes water to its customers. In contrast, Las Virgenes Municipal Water District purchases all of its water from a water wholesaler. This wholesaler is the Metropolitan Water District (MWD) of Southern California. MWD owns and operates drinking water treatment plants but is referred to as a wholesaler because they do not serve domestic customers directly. They sell water to water suppliers who then sell directly to the end user customer. Surface water is carried through pipelines, aqueducts, and canals to the treatment plants for processing before being delivered to customers. The other primary source of drinking water supply comes from underground aquifers. An aquifer is an underground layer of water-bearing permeable rock or unconsolidated materials from which groundwater can be extracted. Groundwater is extracted using wells. Wells can also be owned and operated by a water supplier or they can be owned and operated by a wholesaler who sells the water to a supplier. Distribution Systems Once the source brings the water to the water supplier, it must make its way through a network of pipes, facilities, and various appurtenances in order for water to get to the customer. Below is a breakdown of the primary components of each of these. Pipelines 1. Transmission Mains 2. Distribution Mains 3. Service Laterals Facilities 1. Storage Structures 2. Pump Stations 3. Pressure Reducing Stations Appurtenances 1. Valves 2. Angle Joints 3. Fire Hydrants 4. Meters This list is by no means exhaustive, but it provides a basic overview of a distribution system. Pipelines Pipelines are arteries and veins of a water distribution system. They are in a variety of lengths and sizes and deliver water throughout a wide range of areas. They are commonly referred to as transmission, distribution, and service mains/pipes. Transmission Mains As water is brought from a surface water treatment plant to a water supplier, or as water is pumped from the ground, it must be connected to piping to begin the distribution process. Many times a surface water treatment plant and sometimes drinking water wells are located outside of the area where customers are being served. If this is the case, then transmission mains play an important role in bringing water to the distribution system. Transmission mains are large diameter pipes, which travel long distances carrying large volumes of water. Some transmission mains can exceed diameters of 10 feet (120 inches) or more. Not all water suppliers have transmission mains of this size and some may not travel long distances. Smaller water suppliers might have transmission mains around 24 inches in diameter and only travel a mile or less. Typically there are no service connections to customers off transmission mains unless they are smaller in size and are located within a distribution system. Transmission mains are commonly welded steel and ductile iron pipe. Distribution Mains As water makes its way into a distribution system the pipe sizes become smaller. Distribution mains typically range in size from 6 inches up to 24 inches in diameter. This is not to say there are never distribution mains larger than 24 inches in diameter, it is merely a general description. Unlike transmission mains, distribution mains have customer services connected to them. There are three common network structures distribution mains are laid out in: arterial, grid, and tree. The “tree” network is typically the least desirable since they result in multiple dead ends. A dead end is a pipeline, which ends without any connections on the end of it. For example, most cul-de-sacs are dead ends. A grid network is usually the most desirable because all the pipelines within the grid are interconnected. Distribution mains are most commonly ductile iron pipe. However, polyvinyl chloride (PVC) is also extensively used. Asbestos cement pipe is often found in older water systems and is not typically installed any more. These network layouts and pipelines in general will be discussed in more detail in Water 040 and 041. Service Laterals In order for water to get to each customer individually, pipes need to be connected to a distribution main and brought to the customers parcel. Service laterals are these pipes. They are typically made of copper or plastic and connect to a distribution main and run to the customer’s parcel, connecting to a water meter. The picture below refers to the “distribution main” as a water main and the “service lateral” as a service line. It is also important to point out in this particular picture there is no water meter or valves connecting the pipes. However, it is a nice reference for illustration purposes. Facilities A water supplier has a variety of facilities to store and move water through the distribution system. The information below is not a complete list of facilities but it is a basic overview of common facilities within a distribution system. Storage structures, pumps, and pressure control valves are common among most water distribution systems. Storage Structures Storage is an important requirement for distribution systems. Storage provides pressure and water demand for daily operations, maximum day demands, and enough flows for putting out fires. In order for water to flow through pipes there needs to be pressure. If pumps are not running, then something else needs to provide the pressure. This is where storage structures come into play. Next time you drive around the Santa Clarita or San Fernando Valleys look up on the surrounding hills and you will see tanks scattered around. These cylindrical shaped tanks are above ground water storage tanks. Above ground storage tanks are not the only type of distribution storage, but they are the most common in California. Depending on the topography of the area, the tanks might be placed at various heights throughout the system. Some might be at lower elevations and others at higher elevations. These varying elevation differences are referred to as “pressure zones.” Pump Stations A pump station is used to pump water from lower elevations to higher elevations. In order for water to get to these storage structures, pumps are needed to do the lifting. If a community were completely flat there might not be a need for pump stations. Groundwater wells could possibly provide enough pressure to lift water to elevated storage tanks. In areas where there are varying elevation differences, pumps are needed to lift water to the different pressure zones. This is not to say pumps are only providing water to storage tanks. However, the level of water in a tank is commonly used to determine when a pump needs to be turned on and off. Look at the example below. Imagine homes scattered around the line between the pump and tank too. When the level in the storage tank gets low, the pump would need to be turned on to refill the tank. While the tank is filling, customers might be connected to the pipe leading to the tank and use some of the water while it makes its way to the tank. Once the tank is full the pump would then be turned off. Pressure Reducing Stations Sometimes, the distance between the storage tank and a customer can be so great that the pressure the customer receives is too high for normal plumbing systems. In this case a pressure reducing station can be installed to reduce the pressure down to acceptable levels. Acceptable pressure values vary from water supplier to water supplier but a general range of 40 pounds per square inch (psi) to 140 psi is very common. These pressure reducing stations are very similar to a “pressure regulator” you might have at your home. Generally speaking, the maximum acceptable pressure inside a home is around 80 psi. Therefore, since water suppliers can have pressures up to 140 psi or more, it is common for customers to also have pressure regulating devices. Water supplier pressure reducing stations can also be designed to allow water to flow from higher pressure areas to lower pressure areas if pressures in the lower pressure area drop below a previously determined set point. Appurtenances Appurtenance is a generic term and commonly used for miscellaneous components throughout a distribution system. They are the “joints” and parts used to hold the distribution system together, monitor flows, allow to flow, and to stop water from flowing. In this section we will briefly discuss valves, angle joints, fire hydrants, and meters. Valves The primary purpose of a valve is to stop the flow of water. These are installed throughout water distribution systems to stop the flow of water especially when there is a break in a pipe. As with pipelines, valves come in various sizes. For example, if a water main is 12” in diameter, then the valve is usually 12” in diameter. There are valves on transmission mains, distribution mains, and service laterals. There are also shut off valves connected to most customer meters. When a repair needs to be made or some modification to an existing system needs to be performed the flow of water needs to be stopped. Therefore, valves are a critical component to a water distribution system. Valves connecting a distribution main to a service lateral are commonly referred to as corporation stops (corp stop). Valves located at meter connections are typically referred to as angle, curb, and meter stops. Below are a couple examples of valves. Valves Figure 6.4 Figure 6.5 Figure 6.6 Angle Joints An angle joint is very similar to a joint in your body. Its use is to allow a pipe to change directions. If a pipe is installed in a street and the street turns to the right, the pipe needs to turn to the right too. If the turn is a 90 degree turn, then the angle joint would be referred to as a 90° elbow. There are a variety of different angle joints. The more common ones are at the following angles: 90°, 45°, and 22 ½°. If pipes coming from different directions need to be connected, then a “tee” or a “cross” would be used. See the examples below. Fire Hydrants Fire hydrants are critical appurtenances in a distribution for putting out fires and keeping insurance costs lower. Fire hydrants allow water to flow at high volumes in order to help fight fires. Fire hydrants are also used to flow water for cleaning out sewers, provide water to trucks for dust control, and as a means to “flush” a distribution system for water quality purposes. Water sitting in pipelines for long periods of times without being used can become stagnant and discolored. Therefore, from time to time fire hydrants can be used to “flush” out a system. If a fire hydrant is broken or for some other reason “out of service”, it is important that it is identified as not working. Therefore, if the fire department needs to put a fire out they are not wasting any time connecting to a not functioning hydrant. Fire Hydrants Figure 6.9 – Fire hydrant. Figure 6.10 – Flushing a fire hydrant. Meters The last appurtenance we will discuss in this text is a water meter. Meters are very important for tracking the amount of water traveling in, out or through a distribution system. Meters are commonly placed on pump stations and wells to track the water being pumped into a distribution system. Or, if the pump station is boosting water to a different zone, it is important to track the amount of water entering a particular zone. The most common location for water meters is at the customer service connection. Especially in areas where water is scarce, it is extremely important to be able to track the amount of water a customer uses in order to accurately charge them for the cost of water. Meters also come in various sizes and types depending on the amount of flow needed for the respective service connection. Water Meters Figure 6.11 – Meter. Figure 6.12 – Meter. The information provided in this chapter (as with all chapters in this text) is a snapshot look into distribution systems. In Water 040 and 041 of the Water Systems Technology program you will take a more in depth look at this and more water distribution information. Careers in Drinking Water Distribution There are a variety of career opportunities working for a water distribution supplier and depending on the size of the organization, there can be multiple levels of each position with multiple departments. A large organization such as Los Angeles Department of Water and Power (LADWP) has over 4,000 employees. They have multiple departments with very specific tasks and responsibilities. For example, they might have a meter reading crew that only reads meters. Whereas in a smaller water utility, a meter reader might also be responsible for leak inspections at the meter service, hanging shut-off notices for non-paying customers, and other functions. In even smaller agencies, an employee might read meters one day, fix a leak the next day, and conduct well and pump maintenance on another day. Below is list of some of the more common job opportunities and a brief description of some of the responsibilities. Meter Reader Responsible for reading water meters for customer billing persons. Typically requires walking from service to service, bending down to lift a meter lid, and making note of the meter read. Customer Service Representative Responsible for assisting with sending out water bills, answering customer calls, processing customer payments, and creating work orders based on customer complaints. Water Quality Technician Responsible for the collection of water quality samples, reading and interpreting water quality results, writing reports, and ensuring the water being served to customers is in compliance with drinking water quality regulations. Well and Pump Maintenance Performs daily visits to well and pump sites to ensure proper operation. Collects meter reads, changes oil, monitors and maintains disinfection systems, keeps sites clean, and various other maintenance responsibilities. Managers and Supervisors There are various department managers and supervisors for both field and office staff. Their responsibilities range from organizing and assigning work tasks, creating and monitoring budgets, report writing, and other specific tasks related to their department. This is only a small snap shot of possible opportunities within a water distribution utility. There are many more areas of specific focus such as engineering, human resources, administration, accounting, and construction, just to name a few. However, it is a good list to give a person some perspective on the operations of a distribution system.

textbooks/workforce/Water_Systems_Technology/Water_120%3A_Introduction_to_Water_Systems_Technology/1.06%3A_Water_Distribution_Systems_and_Operations.txt

Water treatment is one of the most critical steps in the drinking water process. It is critical to remove unwanted particles, inactivate harmful organisms, and treat to a level that complies with the Safe Drinking Water Act (SDWA). Most water treated within drinking water treatment plants comes from surface supply sources. As snow melts and rainfall moves along the ground surface into rivers, streams, and lakes, particles are picked up along the way. Therefore, ALL surface water to be used for domestic drinking water purposes must be treated. Surface water is also more susceptible to contamination because much of this contamination comes from “runoff”. Every time it rains or as snow melts, water is washed down from mountains, hillsides, roads, and other areas, picking up anything along the way. For example, imagine a farm next to a stream that feeds a local lake used as a drinking water storage reservoir. There is a potential for animal waste among other things making its way to the storage reservoir. Just the sediment from a lake’s hillside and the natural organic matter in a lake makes the water not suitable for drinking. Therefore, there are regulations within the Safe Drinking Water Act called Surface Water Treatment Rule (SWTR), which specifically addresses surface water treatment requirements. There have been several iterations of this rule to improve the quality of drinking water. The SWTR is crafted to prevent waterborne diseases caused by microorganisms. The rule requires water systems to filter and disinfect water from surface water sources to reduce the occurrence of unsafe levels of disease causing microbes. One of the primary constituents the SWTR requires treatment and monitoring for is turbidity. Turbidity is the cloudiness or haziness seen in water samples and prevents the performance of filtration systems. Low turbidity requirements are used to protect against certain microbial contaminants, in particularly Cryptosporidium. Cryptosporidium is a protozoan that can cause gastrointestinal illness in humans, which is similar to many disease causing microorganisms. The lower the turbidity levels, the less likely there will be disease causing microorganisms. The SWTR also requires disinfection to protect against these pathogens. Disinfection chemicals, such as chlorine, are used to inactivate (kill) pathogens during the treatment process through a required residual present in the water throughout the distribution system. Surface waters also have to be treated for aesthetic qualities. An aesthetic quality doesn’t typically have an effect on public health. These types of qualities are usually related to the appearance and palatability of the water. Does the water taste good, look good, and smell good? Taste, odor, and color are three qualities surface water quality is treated to improve. Particles in Water Particles in water can be broken into three (3) general categories: suspended solids, colloidal compounds, and dissolved solids. Microorganisms fall under the colloidal compound category. One of the main goals of a surface water treatment plant is to prevent the outbreak of disease from microorganisms. These disease-causing agents are referred to as pathogens. The three main pathogen categories are distinguished as bacteria, virus, and protozoa. In drinking water quality, these organisms are not specifically analyzed in samples. Specific organisms, viruses, and protozoa can be very costly and require extensive sampling techniques. Some of the more common pathogens, which can be found in water, are: • Bacteria – Escherichia coli (E. coli) and Vibrio cholera • Viruses – Enterovirus and Coronavirus • Protozoa – Cryptosporidium parvum and Giardia lamblia Instead of analyzing for these organisms specifically, a class of organisms called total coliforms (TC) is used analyzed instead. TC is referred to collectively as indicator organisms. The presence or absence of TC bacteria indicates the presence or absence of pathogens. The analytical test is easy, inexpensive, and very effective. Microorganisms are one class of “particles” removed or inactivated from water. Microorganisms are difficult to remove from water, therefore they are usually destroyed or inactivated through the treatment process. In contrast to colloidal compounds, suspended solids are more easily removed. Much of the suspended material found in surface water supplies is referred to as turbidity. This turbidity comes from decaying plant material and soil as water runs across land and makes its way to streams and lakes. While suspended solids are not typically associated with disease, they can shield microorganisms from treatment processes and provide an overall poor quality to the water supply. Dissolved compounds are the most difficult to remove because they are dissolved in the water. Think about sugar or salt mixed in a glass of water. Once it dissolves and mixes in the water a treatment process is needed to remove it from the water. These treatment processes are more complex than the standard drinking water treatment plant. There are a variety of processes including things such as ion exchange, membrane filtration, chemical absorption, and others. If the dissolved compounds do not pose a health threat or if they are below their corresponding Maximum Contaminant Level (MCL), they are not typically treated for in the drinking water treatment process. Pre-Storage Prior to entering a drinking water treatment plant, water is typically held in large storage reservoirs. These “reservoirs” (lakes) provide an area for large amounts of water to collect so the treatment plant has a constant source of supply. These reservoirs can also allow for some settling of solids and many double as a recreation space for fishing, boating, and water-skiing, etc. Entering the Treatment Plant As discussed in earlier chapters, surface water used for drinking is commonly stored in above ground lakes. These storage reservoirs are sometimes used for recreation such as fishing, boating, and water skiing. This recreational use is an important part of the economy and public use. However, they can add additional water quality problems for the water treatment plant. Water leaving these storage reservoirs needs to be free of large debris such as plants fish, trash, wood, etc. In order to take water from the storage reservoir and leave the larger debris behind there are “intake” structures. A surface water intake structure is a screened structure to let water through and keep larger items from entering the treatment plant. The screen size can vary depending on the use of the storage reservoir and the quality of the raw water. Raw water is the term used to identify water before treatment. The picture below shows an example. The water entering the intake structure can either be pumped or can flow by gravity to the treatment plant depending on the location of the plant compared to the storage reservoir. Valves can be used to adjust the flow into the plant and the water is sometimes kept in an onsite storage tank leading into the plant. Inside a Water Treatment Plant Pre-Disinfection Once raw water enters a treatment plant there may be a pre-disinfection process. Some plants use a disinfectant to kill pathogens and other microorganisms prior to the water going through the treatment process. This can be done to prevent certain organisms from entering the plant and having an effect on the various treatment processes. Or it can be done to remove precursors, such as total organic carbon, to prevent disinfection by-products from forming. Newer treatment plants will use ozone as the disinfectant primarily because it is an effective oxidizer and it does not leave a residual in the water throughout the treatment process. Ozone is a trivalent form of oxygen. Simply put it is a compound of three (3) oxygen molecules (O3). If you have ever smelled an electrical spark or a lightning strike, chances are it is ozone that you smelled. It must be used at the point of generation. Unlike chlorine, which can be processed at a chemical plant (for example), a treatment plant using ozone must generate it on site. Ozone has a number of benefits over chlorine. Ozone Compared to Chlorine 1. Stronger disinfectant 2. Does not contribute to disinfection by-products 3. Kills a wider range of organisms 4. Achieves removal of unwanted tastes and odors 5. Reactions are more rapid However, as mentioned previously, ozone does not leave a disinfectant residual in the water. This might be a good thing for a treatment plant, but ozone is not used in distribution systems because a residual is needed. Conventional Treatment vs. Direct Filtration There are two main types of drinking water treatment plants. There are conventional treatment plants and direct filtration plants. Each has benefits and drawbacks. All of which will be discussed in this text. It is important to remember that this text is an introductory text for a very general overview of the waterworks industry. Therefore, details of each treatment process discussed may be omitted and are provided in more specialized courses. The basic difference between a conventional water treatment plant and a direct filtration water treatment plant is a sedimentation basin. A conventional drinking water treatment plant has a sedimentation basin and a direct filtration plant does not. So, why would one be used over another? Below is an example of some of the “pros” and “cons” of a sedimentation basin. Sedimentation Basin Pros • Allows solids to settle out of the water prior to entering the filtration process • Reduces the amount and duration of backwashing filters Sedimentation Basin Cons • Sedimentation basins are large and require a bigger treatment plant • The sludge at the bottom of a sedimentation basin needs to be removed from time to time. We will now look at the other processes typically found in a conventional and direct filtration drinking water treatment plants. The photos provided in this section are courtesy of the Michigan Department of Environmental Quality. Coagulation Coagulation is the process of chemical addition such as “Alum” to the water supply in order for small suspended particles to “stick” together forming floc. The chemicals added produce positive charges to neutralize the negative charges on the particles. The particles stick together becoming larger and larger during this process. Flocculation As the particles begin to stick together, the water is then sent through a series of tanks with “paddles.” These paddles are designed to slowly mix the water, bringing the particles together to form larger and larger particles called “floc.” The mixing process must be gentle enough to not break apart the floc back into smaller particles. Sedimentation In conventional drinking water treatment plants the sedimentation process allows for the forces of gravity to allow the floc to “settle” to the bottom of the basin. Not all the floc will settle. As you might expect, the large particles settle more rapidly than small particles. Also, the slower the water moves through the basin the more particles will settle out. Water in a direct filtration plant moves straight from the flocculation tanks to the next step…filtration. Filtration The filtration process is one of the most critical steps. Filters are commonly constructed in concrete boxes and contain sand and gravel. Sometimes other filter media is used, but many times sand is sufficient enough to remove the remaining suspended particles. The purpose of the gravel is to support the sand and prevent it from leaving the filter. Under the gravel is a structure called an “underdrain.” The purpose of the underdrain is to allow clear filtered water out of the filter while supporting the gravel and sand filter media. The process of backwashing will be discussed later. Post-Disinfection Prior to the water entering the distribution system, it is usually disinfected with a chlorine based disinfectant. Chlorine gas was and still is commonly used to provide a “free” chlorine residual throughout the distribution system. However, because of the water quality risk of disinfection byproducts, many water treatment plants are using a “total” chlorine residual by mixing chlorine and ammonia together. This disinfection process is referred to as chloramination. How much disinfectant is required before water can be provided to customers for domestic use? There are two “standards” when it comes to disinfection. There is a maximum residual disinfectant level (MRDL) and a minimum disinfectant level, which should be provided to the furthest areas within a distribution system. The MRDL is 4.0 mg/L and this level should not be exceeded in the water entering a distribution system. Typical free (chlorine) and total chlorine (chloramination) levels in water leaving a treatment plant can vary, but are commonly between 2.5 and 3.5 mg/L. The minimum residual level, which should be maintained in the furthest areas of a distribution system is 0.2 mg/L. Since microorganisms have the ability to multiply, a “residual” helps prevent regrowth and keeps the water free of pathogens. The previously mentioned dosage values typically provide enough disinfectant to kill/inactivate (disinfectant demand) remaining microorganisms and allow for a constant and minimal residual within the distribution system. The previous sentence used three (3) common terms associated with disinfection; dosage, demand, and residual. 1. Dosage – is the amount of a disinfectant added. 2. Demand – is the amount of disinfectant “used up” by the disinfection reducing agents in the water (microorganisms, organic matter, etc.) 3. Residual – is the amount of disinfectant left in the water supply. Therefore, the following formula is commonly used. Dosage = Demand + Residual The amount of disinfectant added to a water supply (dosage) minus the amount “used up” (demand) equals the amount remaining, which is referred to as the residual. Storage In order for treatment plants to provide large quantities of water to distribution systems, a large amount of storage is commonly required and provided at the treatment plant. This “post” storage can and often times be in the millions to tens of millions of gallons. Therefore, treatment plants require large areas of land for the entire treatment process and storage. Additional Treatment Processes If the influent quality of water coming into a treatment plant or if the water supply a distribution system is producing, (often times from groundwater wells), is contaminated and not within drinking water standards, the water will require additional treatment. Some of these processes include but are not limited to, ion exchange, membrane filtration, and air stripping. Ion exchange, for example, is the process of removing ions using water with opposite charged ions. In Water 050 and 052, you will take a more in depth look at each process and analyze the benefits and challenges a water treatment operator might encounter. Careers in Drinking Water Treatment Because many drinking water treatment plants are wholesale water providers, meaning they sell water to various water agencies, the extent of career opportunities and paths can be quite extensive. They can have careers ranging from field technicians, maintenance workers, treatment plant operators, engineers, water resource professionals, as well as a variety of office and policy related opportunities. For example, Metropolitan Water District (MWD) of California deliveries is one of the largest wholesaler water suppliers in the country. MWD provides approximately 1.7 billion gallons of water per day and is the largest contractor of the State Water Project. In addition to the responsibilities associated with operating a water treatment plant, MWD has an extensive distribution system. They also have the important task of securing sources of supply to ensure there is always enough water for the water retailers who purchase water from them. They have additional responsibilities in the areas of water conservation, legal matters, public relations, human resources, finance, administration…the list goes on and on. They employ almost 2,000 people with jobs ranging from laborers to scientists, to engineers and more. As you can imagine, trying to list and discuss the vast amount of opportunities for an organization like this would be a lengthy process. For an introductory course like this one it would be impractical. Therefore, we will just look at a smaller example of a drinking water treatment plant and focus on career opportunities available for students such as you. Treatment Plant Operator Water Treatment Plant Operators (WTPO) typically work various assigned shifts. It is not usually a typical “8 to 5” type of job. After all, treated, safe drinking water needs to be available to customers 24 hours a day, 7 days a week. Therefore, WTPO need to work around the clock to make sure the treatment process is functioning efficiently. Below is a list of some of the more common tasks and responsibilities of a WTPO. • Ensure the treatment plant is operating • Perform biological, chemical, and physical laboratory tests on water • Interpret test results • Monitor and read gauges, meters, charts, and other treatment performance indicators • Monitor and inspect treatment process equipment and instrumentation • Make adjustments and take corrective action on treatment process equipment • Maintain operational and water quality records • Prepare reports • Participate in training programs In addition, other responsibilities may include cleaning and disinfecting storage tanks, flushing pipelines, and conducting public tours of the treatment plant. Often, plants will have a variety of automated processes and the WTPO will monitor these processes on a computer screen making adjustments through a Supervisory Control and Data Acquisition System (SCADA). Experience and educational qualifications will also depend on the size of the facility, but many entry level positions will require a minimum of a Grade 3 Treatment Operator certification (T3) or a Grade 2 Treatment Operator certification with the ability to obtain a T3 within a year of employment. Since treatment plants may also have an associated distribution system to get water to the utilities purchasing water from them, a Distribution Operator certification may also be required. The more education and experience you can obtain will always help your chances in landing a job. An associate’s or bachelor’s degree is sometimes listed as a “desirable” qualification. Water Treatment Plant Maintenance Worker Just as a distribution system needs maintaining, a water treatment plant also requires maintenance. Pumps and motors can malfunction. Pipes can leak. System process and equipment can breakdown requiring repairs or replacement. Therefore, most treatment plants will have a maintenance crew as part of the staff. Water Quality and Laboratory Staff Many water treatment plants will have their own drinking water laboratory to analyze samples throughout the treatment process ensuring proper function and for adjusting chemical doses. The staff might be in charge of collecting samples and running analytical instrumentation in the lab. They might also be responsible for writing reports and keeping track of water quality data for regulatory compliance.

textbooks/workforce/Water_Systems_Technology/Water_120%3A_Introduction_to_Water_Systems_Technology/1.07%3A_Water_Treatment_Facilities_and_Operations.txt

We have already discussed our water supply in several chapters. Remember, the two main sources of supply for use are surface water supplies and groundwater supplies. And, as you will see in Chapter 10 there are other sources of water used to supplement these two main sources. If you recall, surface water receives its supply from precipitation in the form of rain, sleet, snow, etc. Moist warm air rises and condenses on upward slopes. On the west coast, rain falls mostly on the westward facing mountains and as dry air drops a rain shadow effect occurs on the east facing slopes. Much of this precipitation runs off into streams, rivers, and lakes. Evaporation occurs condensing water back into the atmosphere. Some of it percolates into the ground and becomes groundwater. Plant roots also take up some water and transpiration occurs. The process of water transpiring and evaporating back into the atmosphere is referred to as evapotranspiration. When precipitation occurs the entire cycle is continued. This cycle is known as the hydrologic cycle. Most of the water on earth is salt water. In fact 97% of the earth’s water is seawater and only 3% is fresh water. This means of all the water on the planet, we get our fresh water from 3% of it. The story continues. Approximately 69% of all fresh water is in the form of glaciers and icecaps. Groundwater is approximately 30% and surface water is less than 1%. This is fairly startling considering much of the water we use every day comes from a fraction of the fresh water on earth. The vast majority of this small fraction is found in lakes. Some of these lakes are natural and some are manmade storage reservoirs behind dams. Much of the water that supplies California sits in these “manmade” storage reservoirs as the water moves through several aqueduct systems. California Surface Water California’s diverse climate and geography presents an interesting situation when it comes to water supply. Approximately 2/3 of the state’s rainfall occurs in the upper 1/3 of the state, while 2/3 of the usage occurs in the lower 1/3 of the state. In other words, water is used more in areas where it doesn’t naturally fall from the sky. Therefore, surface water supplies are plumbed thousands of miles across California. There are 6 main aqueduct systems providing surface water throughout the state. They include: • State Water Project • L.A. Aqueduct • Colorado River Project • Hetch Hetchy Aqueduct • Mokelumne Aqueduct These aqueduct systems originate in the central to northern portion of the state and are operated by a variety of agencies. State Water Project The California State Water Project (SWP) originates from the tributaries of Lake Oroville, north of Sacramento. It runs a distance of approximately 600 miles and includes twenty-nine (29) dams/storage reservoirs, eighteen (18) pumping plants and five (5) hydroelectric power plants. It passes through the California Bay Delta. The Bay Delta is one of the nation’s largest and most complex water delivery system and is known for its agricultural productivity, ecological diversity, and complexity. The SWP also includes the world’s largest water lift. The Edmonston Pumping Plant at the base of the Tehachapi Mountains pumps (lifts) water 2,000 feet over this mountain range. More than 2/3 of Californians receive water through the SWP. The California Department of Water Resources (DWR) operates the State Water Project. Los Angeles Aqueduct In contrast, the Los Angeles Aqueduct is owned and operated by the Los Angeles Department of Water and Power. In the early 1900s, William Mulholland and Fred Eaton traveled north to find additional sources of supply for Los Angeles. What they discovered was the Owen’s Valley, which had more water than the area knew what to do with. They built an aqueduct approximately 223 miles from the Valley diverting water down to Los Angeles. The unique thing about this aqueduct system is it flows entirely by gravity. The book and movie titled Cadillac Desert documents the vast undertaking by William Mulholland. Colorado River Aqueduct The Colorado River Aqueduct begins at Parker Dam along the Colorado River and travels approximately 242 miles west into California. There are two (2) storage reservoirs along the way and five (5) pumping stations to traverse the desert. The Metropolitan Water District of Southern California holds the priority water rights on the Colorado River Aqueduct. Groundwater Underground aquifers hold a vast amount of water. Pores in the soil and fractures in rock formations hold millions of gallons of water beneath the earth’s surface. As rain falls and snow melts, rivers fill with water and recharge these underground storage basins. There are three (3) main types of aquifers, each with unique geological characteristics. An unconfined aquifer can be very shallow, around 20 feet below the earth’s surface to several hundred feet deep. These aquifers are commonly made of alluvium deposits consisting of porous, water-bearing materials of sand and gravel. These aquifers are capable of yielding large amounts of water and relying on annual recharge to keep them full of water. Beneath unconfined aquifers are confined aquifers. These aquifers are separated by an impermeable layer of soil (commonly clay) with porous sand and gravel beneath the clay. This impermeable layer acts as a barrier between the soil sediments above acting as a protective shield. Confined aquifers are less susceptible to surface contamination because of this impermeable layer. Fractured rock aquifers are not very common, but they can exist in mountain regions where there are cracks or fissures in the underlying rock. Water from precipitation can then make its way into the cracks and can be withdrawn by wells. Most wells require a pump and motor to get the water from below the ground to the surface. However, where recharge zones are higher than the elevation, the water can flow out without any help. These types of aquifers are referred to as artesian. Groundwater banking or aquifer storage and recovery (ASR) is becoming increasingly popular, especially in areas prone to experience drought. Water can be pumped into an aquifer through injection wells or spread across acres of land allowing the water to percolate into the aquifer. This type of water storage is often done using surface supplies when water is plentiful. Instead of allowing the surface water to flow to the ocean, it can be diverted into an underground storage “bank”. What is Water? When discussing water, sometimes we often overlook the very unique qualities of this vital resource. Water is composed of three (3) atoms. There are two (2) hydrogen atoms attached to one (1) oxygen atom. The bonding of these atoms to form a water molecule is what truly gives water its amazing characteristics. A water molecule is a polar compound, meaning it has the hydrogen ion bonds angled away from the oxygen atom. The oxygen atom has an affinity for positively charged ions while the hydrogen atoms attract negatively charged ions. This polarity allows water to bond with a variety of compounds making water a “universal” solvent. Water is found in three different phases; liquid, solid, and gas. The ability of water to attract other water molecules is called cohesion. This characteristic creates surface tension of water. A simple experiment to see surface tension in action is to float a paper clip on water. Fill a glass and gently place a paper clip on the water. The surface tension among the water molecule bonds allows the paper clip to float. Adhesion is ability of water to attract other molecules. This attraction to other molecules can be seen by the meniscus in a cylinder. Water attaches to the sides of the cylinder causing it to “creep” up the sides. Some substances are not attracted to water molecules preventing them from dissolving in water. For instance, fats and oils are considered hydrophobic because they do not dissolve in water. Conversely, hydrophilic substances such as salts and sugars dissolve quite easily in water. Water Rights Does everyone have a right to water? Well, on the surface this seems like an easy answer. Everyone should have the right to a safe, clean, and affordable water. However, this isn’t always the case. Water rights laws are very complex and simply stating everyone has the right to access drinking isn’t always enough. Typically, in highly populated cities, the “right” to water isn’t a big issue. However, accessing a safe, clean, and reliable supply in rural areas isn’t always possible, let alone feasible. In 2012, California enacted Assembly Bill 685 establishing a state policy that every Californian has a human right to safe, clean, affordable, and accessible drinking water. This sounds great, but making this a reality is very difficult to accomplish, especially in very rural areas where the infrastructure doesn’t exist to provide the water. Who actually “owns” the water we use every day? Water rights are held by a variety of different private and public entities. Individual farmers can own water rights as well as large municipalities. Water rights are commonly land-based rights. Rights can be allocated based on land ownership or possession. Another type of water right is termed “riparian” rights. This type of land-based right gives the owner of land adjacent to the bank of a water body the right to the water flowing next to their property. Water rights can be also based on use. Use-based rights grant the user certain rights based on the amount of water previously used. Use is given for certain beneficial uses. This can also be for municipalities serving a certain population. Most water rights are associated with surface water supplies. Groundwater is often left to the people owning groundwater wells and pumping water out of the underlying aquifer system. At times this can be contentious if one entity is considered to be pumping more water than others deem is appropriate for the area and or use. This type of contention can result in something called adjudication. Adjudication is a legal process to determine who has a valid right to the water and how much of it can be used by each entity.

textbooks/workforce/Water_Systems_Technology/Water_120%3A_Introduction_to_Water_Systems_Technology/1.08%3A_Water_Supply.txt

It is amazing what water is used for and how much is used on a daily basis. We tend to not think about all the daily activities we do which requires the use of water. We turn on the faucet in the morning without giving it much thought. We flush the toilet, make coffee, and shower without the consideration of where or how the water comes out of our tap. If we think about the simple and obvious water uses, we might list washing our face and hands, taking showers or baths, brushing our teeth, making coffee, boiling pasta, washing dishes and clothes, flushing toilets. However, the list of water use goes on and on. In addition to the obvious uses (i.e., drinking, bath, irrigation, etc.) millions of gallons are used in the manufacturing and processing of everything from semiconductors to beer and everything in between. Water is a vital resource for public health and safety and plays a significant role in our economy. One of the largest water uses in California is the agriculture industry. According to the Pacific Institute’s 2009 report titled Sustaining California Agriculture in an Uncertain Future, approximately 17.2 million acre-feet of water is used for agriculture annually. In addition, a large portion of the state’s water supply is undeveloped and used for environmental purposes. Water use can be broken down into several different categories: geographic, socioeconomic, availability, reliability, and quality. Geographically where water is plentiful very little is used for outdoor irrigation and sometimes use isn’t even tracked. In contrast, in areas of the world where precipitation is low and water is scarce, it is treated differently and very little is used for outdoor irrigation. In poorer areas of the globe, water is a vital resource for survival. Approximately one (1) billion people lack safe and adequate water. In these regions people are not concerned with keeping a lawn green with water. They are worried about surviving. Availability, reliability, and the quality of water also play an important role in usage patterns. Industrialized countries tend to have water readily available, with reliable infrastructure, and of high quality. However, as we have seen in recent years, in certain areas, such as Australia and California, long droughts can occur, jeopardizing water availability, reliability, and quality. The point of this introduction is not to memorize facts and figures; it is to illustrate the vast amount of water uses and variability of supplies throughout the world. The remainder of this chapter will focus on common water uses primarily in California. As mentioned above, water plays an important role in the manufacturing of items. The following table is an example of how much water is needed to prepare certain items. ITEM GALLONS OF WATER Pair of Jeans 1,800 Cotton T-Shirt 400 Barrel of Beer (32 gallons) 1,500 Single Board of Lumber 5.4 Gallon of Paint 13 Individual Plastic Bottle of Water 1.85 Units of Water Whenever we discuss water we talk in volumes. However, there are various units to measure volumes of water. Each unit has its own purpose and are commonly interchanged with each other. Below is a partial list of units and the common use for reporting. USE UNIT Meter Reads Cubic feet (cf) Hundred cubic feet (HCF / CCF) Groundwater Well Flow Gallons per minute (gpm) Daily Production Million gallons per day (MGD) Annual Production Acre-feet per year (AFY) Per Person Gallons per capita per day (GPCD) Understanding the terminology and units used in any industry is very important. The water industry uses a variety of different units and has a lot of terms not used in any other industry. As you start taking more classes in this field and begin your career in water you will become acquainted with the “language” of the industry. As shown in the above table, the common unit of measure to track water use on a per person basis is “gpcd”, which is gallons per capita (per person) per day. This is the amount of water used by one person per day. It is typically calculated by taking the total water demand (use) for the year and dividing it by the total population served. This will give you the amount of water each person uses for one year. Dividing it by 365 (the number of days in a year) will yield the gpcd, the gallons per person (per capita) per day. This number and unit were not used very often in the industry prior to 2009. In 2009, the governor of California passed legislation for conserving water and one of the parameters used to measure the required amount of conservation required by water suppliers is gpcd. Senate Bill X7-7 requires water suppliers to conserve at least 20% of their water demand by the year 2020. Hence, the bill is commonly referred to as 20x2020 (20 by 2020). In order to conserve water it is important to identify water use. Where is the water being used? This may seem like an obvious statement, but being able to identify where the most water is being used can help in targeting specific areas for conservation. For example, gpcd includes both indoor and outdoor water use from residential customers. As previously stated, it is simply the total amount of water used divided by the total population. However, it doesn’t distinguish between indoor or outdoor water uses. It also doesn’t discern between other uses such as business or industry (these will be discussed later in the text.) In the next section we will analyze and assume the entire population of the first few examples is a residential community. Therefore, the gpcd would be for all residential water use both inside and outside the home. GPCD Water usage varies from person to person, city to city, state to state, and more importantly climate to climate. Geography and socioeconomic status also plays an important role with water use. Little irrigation water is needed in areas with high amounts of precipitation. However, sometimes in areas with very little precipitation, little is used for outdoor irrigation too. For example, the gpcd for someone living in an area where there is a lot of annual precipitation will more than likely have a lower gpcd than compared to someone living in a warmer climate. Socioeconomic status will also have an effect on water use and gpcd. A single person living alone in a small apartment will probably have a lower gpcd than someone living in a Beverly Hills mansion with a large yard. Someone with high efficiency appliances, low flow toilets and faucets would tend to have a lower gpcd than someone with access to these types of things. Below is an example of the differences between geographic regions and the respective gpcd values. Average Daily Per Capita Water Use in Several Major U.S. Cities Metropolitan Area GPCD Phoenix, AZ 115 New York, NY 78 Seattle, WA 52 Sacramento, CA 280 San Diego, CA 143 Before even looking at the actual gpcd values in the above table, you could probably guess which city would have the lower and which would have the higher average gpcd values. The only city which may have tricked a few people could possibly be Phoenix, Arizona. Phoenix is a very hot and arid city and one might expect a very high gpcd. However, the gpcd value is considerably lower to a similarly hot and arid Sacramento community. Why is this? If you have ever traveled to Phoenix and Sacramento, the difference between most of the homes in Sacramento compared to Phoenix is the type of landscaping at an average sized single family home. In Phoenix, many homes have “native” or natural landscaping such as rocks and cactus. In contrast, many Sacramento homes have grass (turf) for landscaping. There are other reasons why Sacramento has a higher gpcd than Phoenix, but this is one of the more obvious reasons. Water use is dependent on availability, reliability, and quality. Let’s now take a look at a hypothetical gallon per capita per day (gpcd) calculation to work with as an example to identify water use. Typically when a gpcd is calculated it is not done based on individual water usage. It is commonly calculated based on total annual consumption divided by the total population served. Assume a population of 5,000 people uses 1,120 acre-feet of water in one year. What would be the gpcd for this hypothetical community? Using the formula “total gallons divided by total population”, converts to a gpcd of approximately 200 (see below). 1 AF = 325,829 gallons 1,120 AFY x 325,829 gallons = 364,928,480 gallons per year 364,928,480 gallons / 5,000 people = 72,986 gallons per person per year 72,986 gallons per person per year / 365 days = 200 gpcd This type of calculation will be discussed in more detail in the Water 031 Advanced Waterworks Mathematics course. Therefore, you will not be required to perform this type of calculation in this course. It is used as an example and to help explain how water use is calculated and identified. Now that we have an example gpcd, let’s break down the actual usage. California Among all the countries in the world, the United States has the highest average daily water use per person. In fact, on average, the U.S. uses approximately 410 billion gallons of water per day. The majority of this water use comes from surface supplies; about 80% and the remaining 20% comes from groundwater. Thermoelectric power is responsible for approximately half of all U.S. water demand. Irrigation (agriculture) and public water supply makes up just about all the remaining. California water use is strongly dependent on the Mediterranean climate throughout much of the state. However, California also has some very tall mountain ranges with subarctic conditions. The lower flatland areas of California consist of long dry summers, cool evenings, and mild rainy winters. This is why so many people flock to areas in Southern California. A summer day in Santa Monica or San Diego is almost the perfect climate condition; warm (not hot) days and cool evenings. Many of the mountain areas throughout the state experience a more traditional four-season year with snow lasting from November to April. However, because California is a coastal state, the climate is also dependent on the conditions of the Pacific Ocean. This means, there can be times of significant drought and also high amounts of rainfall during weather conditions such as El Nino. Because of California’s unique size and location, there are four (4) main climate regions; Central Coast, Mountain, Central Valley, and Imperial Valley. These four (4) regions have very diverse climate conditions. The Central Coast has more mild than hot summers and more mild than cold winters. Think of San Francisco as an example. The summers in San Francisco are not typically too hot and the winters are not extremely cold. The mountainous regions of California also have typically mild summers. However, in contrast the winters can be very cold with high amounts of rain and snow. The Central Valleys usually experience very hot summers and cool winters. The San Joaquin Valley for example can have summer temperatures, which exceed 100F and also see some snow in the winter. The Imperial Valley (e.g. Palm Springs) is very hot and dry in the summer and the winters are typically very mild with little to no rainfall. Most of the rain and snow occurs in the eastern and northern portions of California. While most of the people live along the coast and southern portions of the state. This presents a unique distribution challenge for water professionals. Bringing water from where it is to where most of the people are is something California does quite well. However, during years of drought the ability to distribute water throughout the state can be costly and difficult. Most of the time there are ample supplies of water in California for all of the various uses. During extremely wet years, there is sometimes too much water and not enough storage and a lot of the supply ends up in the Pacific Ocean. Indoor Water Use In this section we will analyze some potential indoor residential water use and compare it to the 200 gpcd we calculated in the previous section. If indoor and outdoor uses are not metered separately, certain assumptions will have to be made to distinguish between the two main areas of use. A lot of research and study has gone on and continues regarding water use. In January 2010, the California Homebuilding Foundation published a document titled “Water Use in the California Residential Home”. Many of the estimates used in this section were collected from this document. However, it is important to note this is a “fluid” topic (pun intended) and regulations and policies are constantly changing when it comes to water use and conservation. Now that we have established a 200 gpcd for this example community, we know how much water each person uses on an average per day. There are a number of variables affecting the actual use per individual, but this is the actual average gpcd for this example. Once the average gpcd is calculated you can break down the usage. First, let’s identify typical indoor uses. There are a number of different indoor water uses. For example, flushing toilets, brushing your teeth, bathing, washing your hands, cooking, cleaning dishes, and cleaning clothes. In addition to these common uses a certain amount of water can be lost through leaks in the plumbing system. There are obvious leaks such as a broken pipe or fixture. However, some leaks can go undetected for days or possibly longer. Toilets are probably some of the more common areas where leaks occur. The slightest little crease or crack in the rubber seal in the toilet tank can cause water to slowly drip into the bowl without being noticed. This is just one example of leaks which can account for a high percentage of water use both indoors and outdoors. The list of indoor water use can be larger, but this is a good start. Look at the table below for some estimated amounts and volumes of indoor water use. USE AMOUNT (%) Volume per Use Time/Quantity of Use TOTAL based on 200 gpcd Bathing 8% 2.5 gpm 8 min 16 gal Toilets 3% 1.6 gpf 4 6.4 gal Faucets (cooking/washing) 6% 2.2 gpm 5.5 min 12.1 gal Clothes Washer 2% 1 load per week 25.5 per load 3.6 gal Other/Leaks 8% 16 gal Total Gallons per Day 54.1 gpd Based on the information in the above table, the indoor usage would account for approximately 27% of a person’s usage with a 200 gpcd. This is to say 54.1 gallons of indoor water use divided by a total water use of 200 gpcd equates to about 27%. If 27% is identified as indoor water use, then the outdoor (or irrigation) usage would account for approximately 73% or 145.9 gallons per day. In the space below, make a list of your various indoor uses and estimate how much water you use per day in your home. Use Time or Frequency Volume Outdoor Water Use Sticking with the same 200 gpcd example, the average outdoor water use equates to approximately 73% or 146 gpcd. In California, the average outdoor residential water use ranges from approximately 60 - 75%. Most of this water is used to keep lawns green. Drive around any single family residential community in California and you’ll see acres and acres of turf. This green lush landscaping requires significant amounts of water to keep it green, especially in some of the dry semi-arid inland communities across the state. However, in 2015, the State Water Resources Control Board (SWRCB) adopted water conservation regulations mandating urban water suppliers to reduce water consumption on average of 25%. In addition, new home building standards are becoming stricter making it almost impossible to install grass as the normal focal point in front and backyards throughout California. As usage patterns change, there are still millions of homes with front and backyards covered in grass. So, how much water is used to irrigate a lawn. New efficient drip, micro-spray, and irrigation systems are coming out every day, but many outdoor irrigation systems use standard “sprinkler heads.” The amount of water sprayed out of a sprinkler head varies, but the average nozzle produces approximately four (4) gallons of water per minute. Let’s look at a hypothetical example. Assumptions: • 1 sprinkler head produces four (4) gallons per minute • 7 sprinkler heads per irrigation station • 5 irrigation stations • Each station operates for 10 minutes per day Based on the assumptions above, let’s calculate how much water this irrigation system produces in one day. 7 sprinkler heads x 4 gallons per minute per head = 28 gallons per minute 28 gallons per minute x 10 minutes = 280 gallons per station 280 gallons per station x 5 stations = 1,400 gallons per day You can see by this example, the amount of water used for outdoor irrigation can add up in a hurry. In fact, based on the 200 gpcd example we used in the above example this would equate to a much higher gpcd. One other thing needs to be mentioned regarding the 200 gpcd. Remember, this is for one person. Someone with the irrigation system used in the above example may be from a family’s home. So, let’s assume the irrigation system is from a family of four (4) and they are not watering daily. Let’s assume they are watering three (3) days per week. How does this look in terms of a gpcd? First, take the 200 gpcd and multiply it by a family of four (4). 200 gpcd x 4 = 800 gpcd for this home Next, take the 1,400 gallons per day, multiply it by three (3) days a week and then divide it by seven (7) days a week to get the per day amount. 1,400 gpd x 3 days = 4,200 gallons per week 4,200 gpw / 7 days in a week = 600 gallons per day The 600 gallons of outdoor water use is for the entire family of four. As a percentage, this equates to approximately 75%, which is consistent to the example given above. Now, divide this by four (4) for the family. 600 gallons per day / 4 people = 150 gallons per person per day Therefore, in this example, one (1) person uses 200 gallons per day with 150 coming from outdoor uses and 50 from indoor uses. If you remember the indoor usage calculated in the earlier example it was 54.1 gallons, similar to the results in this exercise. Please note that this is just one example in a very complex and diverse world, but it should illustrate the point of how indoor and outdoor uses can be estimated. Other Water Uses This section will focus on other uses in California. The California Department of Water Resources (DWR) breaks down California’s total water use into three (3) main broad categories: Urban, Agricultural, and Environmental uses. Urban use includes domestic residential use as previously described. In addition, urban water use includes commercial, industrial, and institutional uses. These three (3) categories make up a component of water use in California and throughout the world. In California, these use categories are defined by the DWR. • Commercial: Water users that provide or distribute a service. • Industrial: Any water users that are primarily manufacturers or processors of materials as defined by the Standard Industrial Classifications (SIC) Code. • Institutional: Any water using establishments dedicated to public service. This includes schools, courts, churches, hospitals, and government facilities. As you can imagine, the use percent for these three (3) categories can vary widely based on the area. For example, the amount of commercial, industrial, and institutional water use in a small “bedroom” community would be quite low. However, in a city such as San Pedro, California, where there are a variety of industries this component of usage can be quite high. In California, these categories only account for a small percentage of all urban water use. Agricultural and Environmental Water Use In California, it is estimated that the agriculture industry accounts for approximately four (4) times as much water use as all urban water uses. This is not surprising since California’s unique geography and Mediterranean climate have allowed the State to become one of the most productive agricultural regions in the world. California produces over 250 different crops and leads the nation in production of 75 commodities. California agriculture irrigates approximately 9.6 million acres of land. Environmental uses are identified as coming from developed and undeveloped water supplies. A developed water supply is one controlled and operated by someone. For example, the State Water Project is a developed water supply controlled and operated by DWR. It comes from natural runoff from precipitation and snow melt runoff, but it has been developed into a supply for specific uses. In contrast, an undeveloped supply would be a “free” flowing stream or river which is not used for specific uses. Both of these supplies are used for and by the environment. Among other things, developed flows are needed to keep salinity levels lower in the Sacramento Bay-Delta area and to help keep cold, clean water needed for salmon migration and spawning. According to DWR, roughly 52 percent is used for agriculture, 14 percent for urban, and 33 percent for environmental uses.

textbooks/workforce/Water_Systems_Technology/Water_120%3A_Introduction_to_Water_Systems_Technology/1.09%3A_Water_Use.txt

Water is one of our most precious and vital resources on earth. Without it, life would not exist. However, at times we all take water for granted. Every time we turn on the faucet at home water comes flowing out. We have learned throughout this text where water comes from, how it is treated, and how it is distributed. We also learned about the hydrologic cycle and how water is transformed from one phase to another. But, what if part of this hydrologic cycle is interrupted? What if it doesn’t rain? What if there is no snow in the mountains? In 2011 – 2015, California was faced with one of the worst droughts in the state’s history. California has seen record low snow pack in the Sierra Nevada Mountains and historically low rainfall throughout the state. In January 2015, San Francisco recorded no rain for the first time in the city’s history. The Governor and the State Water Resources Control Board handed down mandatory conservation regulations in 2015. Some water suppliers were asked to conserve as much as 36%. What if droughts continue for long periods of time? Will conserving water be enough? Conservation is always a prudent approach to saving water, but sometimes it will not be enough to offset the potential loss of water during times of serious drought. Reuse is a term used often in the water industry to identify reusable sources of supply. Recycled (reclaimed) water is one of the most common reuses of water. Recycled Water Recycled Water” can be classified as any water which is reused and has not been processed for drinking purposes. For example, if you have a rain barrel and you collect rain water and use it to irrigate your yard; this can be thought of as a type of recycled water. Storm water runoff can also be looked at as a type of “recycled water.” As it rains and storm water is captured and reintroduced into a groundwater basin to recharge, an aquifer can be considered a form of recycled water. Greywater systems are also a form of recycled water. Grey water is the water collected after uses such as dish and laundry washing machines and reused as irrigation water. Although these previous examples can be thought of as “recycled water”, most people think of recycled water as treated wastewater. Wastewater is solid and liquid discharges from all sources dumping into a municipal sewer system. Sometimes, storm water can enter a sewer system through manholes in a street. However, most storm water makes its way through a storm drain system and eventually flows to the ocean. This water is typically untreated. In contrast, wastewater goes through a series of treatment processes to remove solids, harmful pathogens, and other things to make it acceptable to be discharged back into the environment. The various wastewater treatment stages are referred to as primary, secondary, tertiary, and advanced treatment. Most wastewater used for recycled water purposes goes through at least tertiary treatment. Below is a brief description of each wastewater treatment process. These processes are covered in more detail in the Water 060 and 061 courses. • Preliminary Wastewater Treatment - The removal of large, entrained, suspended or floating objects. The treatment process usually consists of large screens and cutting devices. • Primary Wastewater Treatment - The separation of solids and greases through settling tanks and clarifiers. • Secondary Wastewater Treatment - This step involves the removal of organic matter primarily through biological treatment. • Tertiary Wastewater Treatment - Disinfection chemicals such as chlorine and ultra-violet light are used to remove pathogens (disease causing organisms) from the wastewater. • Advanced Wastewater Treatment - If additional contaminants need to be removed sometimes advanced treatment is employed with the use of membrane filtration and/or additional chemical treatment processes. When discussing recycled water the main purpose is to reduce the burden on fresh water supplies by reusing water such as treated wastewater. Recycled water is commonly discussed in unison with water conservation. The idea is to Reduce the amount of water used, Reuse water supplies for various purposes, and Recycling treated wastewater. The remaining sections of this chapter will discuss these “conservation” related topics and how the three “R”s are incorporated. Groundwater Recharge Groundwater recharge is the process of water from the surface re-entering the ground becoming groundwater. Typically groundwater aquifers are recharged through precipitation. Rain and melted snow makes its way to an aquifer recharge zone and percolates deep into the soil becoming groundwater. However, there are other sources of water which can makes its way to a recharge zone can become groundwater. For example, if a fire hydrant gets hit and water flows into a storm drain which discharges to a dry riverbed with an underlying aquifer can percolate into the soil becoming groundwater. Another example is the treated effluent from a wastewater treatment plant. These types of examples are referred to as “incidental” recharge. Direct Potable Reuse Direct potable reuse is using a source of recycled wastewater directly as potable water. At the time this text was written, this is not an approved source of potable water. There are too many health concerns and unknowns regarding the quality Indirect Potable Reuse Indirect potable reuse is the process of reusing treated wastewater to recharge groundwater basins and aquifers and to augment various surface water supplies. This type of reuse can be something which is termed “incidental” or it can be a planned and constructed use. Anywhere wastewater is treated and discharged back into the environment has the potential to recharge an aquifer. For example, if a wastewater treatment plant is discharging into a dry river bed and this dry river bed has an underlying groundwater aquifer, this would be considered incidental recharge. If there are groundwater wells downstream of this discharge location, this “incidental” recharge would be a potential supply for these wells. Conversely, in Orange County, CA there is the Groundwater Replenishment District which takes highly treated wastewater and pipes it back up into the groundwater basin for recharge. They process enough water to serve approximately 600,000 people. There are however, several challenges when presenting these wastewater reuse strategies. Professionals within the water and wastewater industries have a good understanding of the various treatment and distribution processes of water making it safe and reliable for human use and for the environment. The general public typically has less of an understanding, especially when it comes to reusing wastewater. This lack of understanding usually results in a reluctance of the public. When terms as “toilet to tap” are floated around the media, the public becomes skeptical. In addition to perception, there is a significant cost which goes along with all reuse options. A significant amount of infrastructure is needed to bring water from wastewater treatment plants to the various customers. Many times miles of pipeline is needed as well as pumps and storage. The infrastructure costs can often times be cost prohibitive. However, in new developing communities, the infrastructure costs can be greatly reduce by charging connection fees to developers and because it is much cheaper to install pipe lines in dirt than existing streets in asphalt. There are multiple reasons why recycled water should be used. Since water can be a limited resource in many parts of the world, recycled water can be used for many different non-potable uses where potable drinking water is typically used. For example, an office building can be “dual-plumbed” so the restroom water for toilets is recycled water and the sink water is potable drinking water. By far, the most common use of recycled water is for irrigation. By using recycled water we reduce the reliance of fresh water from sensitive ecosystems, reduce the dependence on importing water, and there is the potential for energy savings by reusing a local resource. These are just a few examples of recycled water uses and benefits from reusing treated wastewater. In addition to the public and costs issues with using recycled water, there are various permitting hurdles with Los Angeles Regional Water Quality Control Board (LARWQCB) and Division of Drinking Water (DDW). The LARWQCB is responsible for promulgating the federal Clean Water Act. As part of this act, it gives the authority of maintaining clean water in what is called “navigable waters of the U.S.” Locally, a navigable water of the U.S. would mean the Los Angeles River and the Santa Clara River. All water discharged into these and other water bodies must meet certain water quality standards known as Basin Objectives. Each watershed can have different water quality objectives depending on the beneficial use of the water in the watershed. Since DDW is responsible for drinking water systems in California, they oversee recycled water use and water used for groundwater recharge. Their requirements involve the quality of the water and how long the water being discharged and subsequently pumped out through groundwater wells for domestic use. In addition, the agency responsible for treating wastewater may also have specific regulatory requirements. In Los Angeles, this would be the Los Angeles County Sanitation District. LA County Sanitation District has permits with the Regional Water Quality Control Boards for discharges and they have also set up specific requirements to use their treated wastewater as recycled water. These and other rules and regulations are not limited requirements, but they do require time for research, analysis, and permitting before recycled water can be used. Below is a list of some of the approved recycled water uses. • Groundwater Recharge – certain LARWQCB and DDW rules and regulations apply. For example, the quality of the water used must meet certain LARWQCB Basin Water Quality Objectives and the quality and distance before the water is pumped out of the ground for domestic use must adhere to certain DDW regulations. • Lavatory Facilities – if the plumbing system of a building is “dual-plumbed”, meaning there are pipes specific for different uses, recycled water can be used for toilets, drainpipe priming, etc. There are specific DDW rules and regulations that apply. Currently (2015) dual-plumbed systems are not allowed in residential homes. • Industrial and Commercial – certain business processes can use recycled water for non-potable purposes. Various regulations apply. In addition to the regulatory requirements mentioned above, some of the specific requirements imposed on water suppliers before they can began using recycled water are the following: • Users must have a Site Supervisor. The water supplier is required to coordinate with the user training and assignment of an onsite supervisor. • Annual visual inspections must be conducted. The Site Supervisor and the water supplier must coordinate these inspections. • Pressure test inspections are also required every four (4) years. In addition to the Site Supervisor and water supplier, a State or County Health Department usually provides an inspector. Locally in the greater Los Angeles area Valencia Water Company, Burbank Water and Power, and Los Angeles Water and Power serve recycled water. Conservation Why should we conserve water? There are a number of reasons why someone would conserve water. During times of drought there may be regulatory requirements for water conservation. Some people may think it is just the right thing to do since water can be a limited resource in certain parts of the world. Or, maybe you just want to try and save a little money. Water rates are always getting higher and higher and the less you use, means the less you will pay. Reusing water, whether it is recycled water for irrigation or recycled water used to recharge groundwater aquifers, is a prudent approach when it comes to water resources. However, water conservation or reducing the amount of water used is also an important tool when it comes to water supply resources. Reducing the amount of water we use will help ensure the availability of water in the future. As the cost of water continues to rise, it is also economically prudent to reduce the amount of water used. In 2009, the governor of California signed into law Senate Bill x7-7. This bill is also known as 20x2020 and requires all water suppliers to reduce their water demand by 20% by the year 2020. The 20% reduction is calculated using the water suppliers average customers daily use or gallons per capita per day (gpcd). Gpcd is calculated by taking the total water production and dividing it by the total population. Daily Production = 9,600,000 gallons Total Population = 40,000 9,600,000 gallons / 40,000 people = 240 gpcd A 20% reduction for this example would equate to a 192 gpcd. In this example, you might be thinking that this is a lot of water for one person to use in one day. However, if you recall from the Water Use chapter, the amount of water used can add up quickly. Regardless of the reasons you decide to conserve water, the bottom line is you will save money. Let’s go back to the 20% savings example above. A 20% daily savings of 48 gpcd for a family of four (4) will equate to over 70,000 gallons a year. Let’s take a look. 48 gpcd x 4 people = 192 gallons per day. 192 gallons per day x 365 days = 70,080 gallons per year Most utilities bill in hundred cubic feet (HCF or CCF) billing units 1 CCF = 748 gallons 70,080 gallons / 748 = 94 CCF Now, we need to make an assumption how much a water supplier would charge for a CCF. Water rates vary, but averages in the southern California area range between \$1.60 - \$3.50 per CCF. Therefore, using the low and high of this range, this family of four (4) would save 94 CCF x \$1.60 = \$150.40 per year 94 CCF x \$3.50 = \$329 per year I don’t think anyone would turn down \$150 a year let alone \$329! So, regardless of the reason you might decide to conserve, there is the potential to save a lot of money. How Do Water Suppliers Get Customers To Conserve? Sometimes people are not aware of how much water they use. They might look at their monthly water and if it looks similar to the month before they do not think twice before paying their bill. Communication is the number one tool water suppliers have at their disposal to promote water conservation. Bill inserts, flyers, social media, and all good ways to communicate to the public about conservation. Some water suppliers may also use billboards and radio and television advertisements. Getting the word out is the first step. Many water suppliers offer a variety of incentive rebates to help people conserve water. Low flow toilets, efficient appliances, drip irrigation nozzles, and “turf” buyback programs are just a few rebate programs water suppliers use. Sometimes water suppliers need to take a more aggressive approach, especially if there is a drought and regulations require conservation. If the public does not respond to outreach programs or rebates, utilities will often resort to increasing water rates and/or issue fines. This is not the most popular approach among customers, but sometimes it is a necessary tool to force customers to conserve water. It is also important to note that sometimes water suppliers will have to increase water rates because of conservation. The less water used means the amount of revenue a utility collects will decline. This is probably one of the most difficult things to communicate to customers. Water suppliers tell customers to use less water and then the water rates are increased anyway. One of the last things a water supplier will use to get customers to use less water is to shut off their water service. This is not usually advisable, because a minimal amount of water is needed to maintain health and safety, but at times, people might have their water service discontinued for a certain period of time until they decide to use less water. Water Rates There are various different rates structures water suppliers use. They include; flat rates, uniform single quantity rates, tiered rates, and water budgets. The type of water rate a utility will use is dependent on a number of factors and vary for area to area. Flat Rate Flat rates are the simplest rate design. The rate is the same or flat for every customer regardless of water use. This type of water rate is common in areas where use is relatively the same for everyone. For example, an area where outdoor irrigation is not needed because of ample amounts of precipitation and indoor use is the predominant use a flat rate might be used. However, some people might deem this type of rate unfair because a large family would essentially pay the same amount as a single person living in a home. This is a very easy rate structure for utilities. No meters are needed and the revenue amount every year is relatively constant. Uniform Single Quality Rate This type of rate structure is considered a more fair way to charge for water and the services associated with treatment and delivery. There is a single rate price for one unit of water. Therefore, if you use one unit (CCF) you only pay for one unit of water. Whereas if you use 100 CCF of water you pay for the 100 CCF you used. It is probably the most common rate structure. Each utility with this rate structure must make sure they review the income revenue often since a large reduction in use will translate to a large reduction in revenue. The amount of money a utility needs to operate is referred to as revenue requirements. This will be reviewed later in this chapter. Tiered Rate Tiered rates are becoming more common, especially in areas where use patterns can fluctuate, such as areas affected by drought. This type of rate structure can be used to encourage conservation. The cost of a unit of water increases the more you use. There can be as few as two tiers and some agencies have up to five tiers. A tier rate structure might look something like this; Tier 1 = \$1.50 per CCF up to 10 CCF (1 – 10 CCF) Tier 2 = \$2.00 per CCF for each unit over 10 CCF up to a certain amount (11 – 20 CCF) Tier 3 = \$3.00 per CCF for anything used over 20 CCF (21 and up) Let’s see how this type of rate structure works. The following example is based on a monthly water usage of 30 CCF. The first 10 CCF of the monthly 30 CCF usage would be billed at the \$1.50 per CCF rate. Therefore, you would multiply 10 CCF by \$1.50. 10 CCF x \$1.50/CCF = \$15 The remaining CCF would be 20 (30 CCF - 10 CCF). The next 10 CCF of water used (11, 12, 13…20 CCF) would be billed at the second tier rate of \$2.00 per CCF. 10 CCF (11 - 20 CCF) x \$2.00/CCF = \$20 The remaining usage up to 30 CCF is another 10 CCF. These remaining 10 CCF (21, 22, 23…30 CCF) would be billed at the third tier rate of \$3.00 per CCF. 10 CCF (21 – 30 CCF) x \$3.00/CCF = \$30 All three total charges would be added together for a total monthly bill amount of \$65. \$15 + \$20 + \$30 = \$65 This is a very simplistic look at a tiered rate structure, but it should illustrate how the cost of water increases based on the amount used. You can see how this type of rate structure might encourage conservation. Water Budgets The last rate structure we will look at in this text is called water budgets. It is a similar structure to tiered rates. However, unlike tiered rates, water budgets provide a more fair and equitable way of charging for water use. In a straight tiered rate structure many people complain because of the subsidization issue. Large use customers pay much more and in some instances subsidize smaller users. This is because a traditional tiered rate structure is blind to parcel size. Water budgets are different. A water budget is an individualized rate structure based on each customer’s specific parcel. For example, a customer with a large yard and multiple people living in their home will have a larger budget than a single person living in an apartment with no outdoor landscaping. Both customers would have a monthly allocation specific to their needs. Water budgets usually classify an indoor allocation of 50 - 60 gpcd and then specify an outdoor allocation based on actual landscape measurements or perhaps a percentage of the parcel size. All this information gets input into a formula to calculate the monthly budget. The formula typically includes a monthly evapotranspiration rate (ETo) and a coefficient for the specific type of landscape material. The evapotranspiration rate is the amount of water needed to sustain plants based on the current weather. For example, the ETo rate is higher in summer months than during the winter. Although this is a more equitable rate structure, it does require additional work by the water supplier and can sometimes be confusing for customers to understand. Regardless of the rate structure, the utility must demonstrate that their rates are truly the cost of providing service. There have been lawsuits in the past and will continue in the future, challenging various rates structures and the amount being charged. Utilities must adequately identify why their rate structure is the needed amount for their specific revenue requirements. Service Charge One last rate component should also be discussed. A service charge is a monthly (or bi-monthly) charge placed on each customer regardless of the amount of water used. This charge is a flat rate and covers some specified percentage of the water supplier’s revenue requirement. It is sometimes referred to as a “readiness to serve” charge. It guarantee’s a certain amount of revenue every billing period allowing the utility to continue basic business functions without worrying about usage fluctuations. Revenue Requirements This term has been mentioned several times in the preceding sections. A revenue requirement is nothing more than the amount of money (revenue) a utility must collect to maintain their basic day-to-day service. Water rates and service charges are the primary source of revenue water suppliers receive. Well, what is a “revenue requirement”? A water supplier has certain expenses, which cannot be avoided. For example, water treatment is required in order to provide a safe drinking water supply to customers. For each gallon of water served it requires a certain cost for treatment. Likewise, there are electrical costs for pumping water, maintenance costs, salaries and benefits for employees, and costs for replacements and improvements to infrastructure. There a many expenses to operate a water utility, but this doesn’t mean there is no room to reduce costs to keep rates low. Each water supplier must determine what is necessary and what can be reduced or cut in order to maintain an efficient operation. Water is a vital resource and the availability of fresh water varies throughout the world and is dependent on weather patterns. An El Niño weather pattern can bring much needed rain to parts of the world while creating devastating droughts in other parts. Understanding the use and need of water will help us all use it a little more wisely and will help professionals manage this important resource. There will always be a need for water professionals as long as clean, safe, and reliable drinking water is needed.

textbooks/workforce/Water_Systems_Technology/Water_120%3A_Introduction_to_Water_Systems_Technology/1.10%3A_Recycled_Water_Reuse_and_Conservation.txt

Fractions are portions of whole numbers consisting of a numerator (or the top number of the fraction) and the denominator (or the bottom number of the fraction.) They are numbers that represent parts of a whole. Fractions are broken down into three classifications: • Proper - \(\dfrac{3}{4}\) - Where the numerator is smaller than the denominator • Improper - \(\dfrac{5}{2}\) - Where the numerator is larger than the denominator • Mixed - \(1\dfrac{6}{7}\) - Where a whole number precedes the fraction Exercise 1.1 Identify the following as a proper fraction, improper fraction, or mixed number. Identify the correct word. \(\dfrac{1}{2}\) Proper Improper Mixed \(\dfrac{10}{12}\) Proper Improper Mixed 3. \(10 \dfrac{1}{2}\) Proper Improper Mixed \(\dfrac{11}{3}\) Proper Improper Mixed \(\dfrac{101}{13}\) Proper Improper Mixed \(130 \dfrac{10}{13}\) Proper Improper Mixed \(\dfrac{1,000}{1,111}\) Proper Improper Mixed \(\dfrac{12}{7}\) Proper Improper Mixed \(\dfrac{1}{7}\) Proper Improper Mixed \(13 \dfrac{1}{7}\) Proper Improper Mixed 1.02: Reducing Fractions Fractions can be reduced (expressed) in their lowest terms. This simply means that the fractions can no longer be divided by any other number. In proper fractions, if the numerator and denominator can be divided by the same number, the fraction can be reduced. Example: \(\dfrac{2}{4}=\dfrac{1}{2}\) In the example above, this is accomplished by dividing the numerator and denominator by the number 2. Two fourths and one half represent the same number. They are just expressed differently. One half is a reduced form of two fourths. Example: \(\dfrac{2}{4} \div \dfrac{2}{2}=\dfrac{1}{2}\) At times a fraction can be divided multiple times in order to reduce it. Example: \(\dfrac{8}{12} \div \dfrac{2}{2}=\dfrac{4}{6} \div \dfrac{2}{2}=\dfrac{2}{3}\) This can also be performed in one step as follows. Both solutions provide the same answer. Example: \(\dfrac{8}{12} \div \dfrac{4}{4}=\dfrac{2}{3}\) In reducing improper fractions the denominator is divided into the numerator to create a mixed number. The remainder is written as a fraction. Example: Remember: The resulting mixed number may also need to be reduced further. Example: Exercise 1.2 Reduce the following fractions to their lowest terms. 1. \(\dfrac{7}{2}\) 2. \(\dfrac{10}{4}\) 3. \(\dfrac{18}{4}\) 4. \(\dfrac{20}{4}\) 5. \(\dfrac{6}{5}\) 6. \(\dfrac{100}{3}\) 7. \(\dfrac{39}{6}\) 8. \(1\dfrac{8}{12}\) 9. \(2\dfrac{9}{4}\) 10. \(\dfrac{4}{3}\) 11. \(\dfrac{14}{3}\) 12. \(\dfrac{140}{200}\) 13. \(\dfrac{10}{20}\) 14. \(7\dfrac{30}{40}\) 1.03: Why Fractions Fractions are very common in waterworks mathematics. You may not see them in their “typical” form, for example: $\dfrac{3}{4} \qquad \dfrac{2}{3} \qquad \dfrac{1}{5}\nonumber$ You may see them as percentages: $75 \% \qquad 66 \% \qquad 20 \% \nonumber$ Or you may see them as words: Three quarters two thirds one fifth However, these examples can also be expressed as fractions. We will discuss these later in the text. By understanding fractions, you can also understand how units are used to express things in terms of fractions. For example, if you drive a car at a velocity of 55 miles per hour, this is a form of a fraction. $\dfrac{55 \text { miles }}{\text { hour }}\nonumber$ Fifty-five miles per hour is in fact a fraction. It is just expressed in a “per unit” example. It can be read as 55 miles per one unit of hour. What if you had an example of 110 miles per 2 hours? This could be written as: $\dfrac{110 \text { miles }}{2 \text { hours }}\nonumber$ Similar to reducing fractions such as: $\dfrac{2}{4}=\dfrac{1}{2} \nonumber$ The previous example of “55 miles per 2 hours” can be reduced as below: $\dfrac{110 \text { miles }}{2 \text { hours }}=\dfrac{55 \text { miles }}{1 \text { hour }} \text { or } \dfrac{55 \text { miles }}{h r} \nonumber$ The concept of “units” will be discussed in more detail later in this text, but understanding the concept is important to learn the process of solving waterworks mathematics problems. Since “adding” and “subtracting” fractions is not a common process in water-related math problems we will skip directly to multiplication and division of fractions.

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/01%3A_Mathematical_Review-_Fractions/1.01%3A_Understanding_Fractions.txt

Multiplying and dividing fractions is a common practice when solving water related math problems. However, the process may not appear to be the multiplication and division of fractions and is commonly referred to as “unit conversion” or unit dimensional analysis. The example below demonstrates this process and will be discussed in more detail later in this text. $\dfrac{2 \text{sqft}}{1} \times \dfrac{3 \text{ft}}{1 \text{sec}}=\dfrac{6 \text{cf}}{\text{sec} } \nonumber$ For now, ignore the “units” and focus on solving the math. “Unit Dimensional Analysis” is a section we will spend a significant amount of time covering. Just look at the above problem as a fraction multiplication problem. Yes, both 2 over 1 and 3 over 1 are simply 2 and 3, but it helps to illustrate the process by looking at them as fractions. $\dfrac{2}{1} \times \dfrac{3}{1}=\dfrac{6}{1} \nonumber$ When multiplying fractions the numerators are multiplied by each other and the denominators are multiplied by each other. In other words, the numbers are multiplied straight across. So, in the example above, 2 x 3 = 6 and 1 x 1 = 1. The resulting answer is 6 over 1 or more simply put 6. However, when “units” are introduced, you can’t just say the answer is “6”. Always remember to reduce as necessary. Look at a couple other examples below: Example $1$ $\dfrac{1}{2} \times \dfrac{1}{2}=\dfrac{1}{4}$ Example $2$ $\dfrac{2}{3} \times \dfrac{4}{6}=\dfrac{8}{18} \div \dfrac{2}{2}=\dfrac{4}{9}$ In the first Example $1$, if you multiply the numbers across as before, you would multiply 1 times 1 and then 2 x 2. The resulting answer would be 1 over 4 or one forth. In the next Example $2$ you can do the same thing. Multiply the 2 and 4 to get 8 and then multiply the 3 and 6 to get 18. The resulting answer is 8 over 18 or eight eighteenths. However, remember to always reduce if necessary. In order to reduce you need to find a number, which will go into both 8 and 18. Since 2 will go into both of these numbers, you can reduce the answer to 4 over 9 or four ninths. Cross canceling is also something you can do. Cross canceling is nothing more than reducing before you multiply. Look for any number that goes into both a numerator and a denominator. In the example below, 2 goes into both the 2 in the first fraction and the 6 in the second fraction. Example $3$ $\dfrac{2}{3} \times \dfrac{4}{6}=\dfrac{\not{2}}{3} \times \dfrac{4}{\not{6}}=\dfrac{1}{3} \times \dfrac{4}{3}=\dfrac{4}{9}$ In the Example $3$, when you cross cancel, you reduce the two-thirds times four sixths to one third times four thirds. Then you multiply the 1 and 4 (numerators) and the 3 times 3 (denominators) to get an answer of four ninths. When multiplying whole numbers and fractions you must first convert the whole number into an improper fraction and then, multiply. Be sure to cross cancel if possible and reduce if necessary. Placing a whole number over a 1 is an important step not only in solving these types of fraction problems, but will also be a helpful tool later in this text. Example $4$ $5 \times \dfrac{3}{5}=\dfrac{5}{1} \times \dfrac{3}{5} \rightarrow \dfrac{\not{5}}{1} \times \dfrac{3}{\not{5}}=\dfrac{3}{1}=3$ The same rules apply when multiplying mixed numbers. Convert to improper fractions and multiply. In order to convert mixed numbers into improper fractions you must multiply the denominator by the whole number. Then add the numerator to the product and put that number over the denominator. Be sure to cross cancel if possible and reduce if necessary. Note: Never leave an answer as an improper fraction. Example $5$ Exercise 1.4 Multiply the following and reduce if necessary. Remember to cross cancel if possible. If you are multiplying a whole number by a fraction, place the whole number over 1. 1. $\dfrac{1}{2} \times \dfrac{2}{4}$ 2. $8 \times 3 \dfrac{2}{5}$ 3. $\dfrac{18}{4} \times \dfrac{12}{9}$ 4. $1 \dfrac{10}{9} \times 4 \dfrac{4}{7}$ 5. $5 \dfrac{9}{3} \times 7 \dfrac{3}{5}$ 6. $\dfrac{21}{24} \times \dfrac{4}{7} \times \dfrac{6}{3}$ 7. $\dfrac{1}{100} \times \dfrac{10}{20}$ 8. $\dfrac{13}{33} \times \dfrac{13}{33}$ 9. $10 \dfrac{12}{15} \times 10 \dfrac{12}{15}$ 10. $8 \dfrac{1}{3} \times 5 \dfrac{3}{5}$ 11. $\dfrac{3}{4} \times \dfrac{6}{9} \times \dfrac{10}{12} \times \dfrac{12}{20}$ 12. $\dfrac{100}{200} \times \dfrac{10}{20}$ 13. $\dfrac{4}{5} \times \dfrac{5}{4}$ 14. $15 \times 7 \dfrac{1}{5}$ 1.05: Dividing Fractions When dividing fractions you invert (flip upside down) the fraction on the right side of the equation (the dividend). Then it becomes a multiplication problem. Invert and multiply! Example $1$ $\dfrac{2}{5} \div \dfrac{1}{2} \rightarrow \dfrac{2}{5} \times \dfrac{2}{1}=\dfrac{4}{5}$ Example $2$ $\dfrac {\dfrac{4}{9}}{\dfrac{8}{9}}$ This example reads $\dfrac{4}{9}$ divided by $\dfrac{8}{9}$. However, after you “invert and multiply,” it becomes: $\dfrac{4}{9} \times \dfrac{9}{8} \rightarrow \dfrac{1}{1} \times \dfrac{1}{2}=\dfrac{1}{2} \nonumber$ After inverting the fraction, the same rules apply as previously mentioned when multiplying fractions. You need to change mixed numbers into improper fractions; you can cross cancel, and always remember to reduce if necessary. Example $3$ $\dfrac{3}{8} \div \dfrac{12}{6} \rightarrow \dfrac{3}{8} \times \dfrac{6}{12} \rightarrow \dfrac{\not{3}}{\not {8}} \times \dfrac{\not {6}}{\not {12}}=\dfrac{1}{4} \times \dfrac{3}{4}=\dfrac{3}{16}$ In the Example $3$ above the 3 divided into itself once and into the 12 four times. Similarly, 2 divided into 6, three times and into 8, four times. Can you see a different way to cross cancel? If the dividend is a whole number write it as a fraction before inverting. Always remember to cross cancel and reduce if necessary. Example $4$ $\dfrac{5}{8} \div 10 \rightarrow \dfrac{5}{8} \div \dfrac{10}{1} \rightarrow \dfrac{5}{8} \times \dfrac{1}{10} \rightarrow \dfrac{\not{5}}{8} \times \dfrac{1}{\not {10}} \rightarrow \dfrac{1}{8} \times \dfrac{1}{2}=\dfrac{1}{16}$ Exercise 1.5 Divide the following and reduce if necessary. 1. $\dfrac{1}{2} \div \dfrac{2}{4}$ 2. $\dfrac{5}{22} \div 7 \dfrac{2}{4}$ 3. $\dfrac{6}{8} \div \dfrac{9}{12}$ 4. $3 \dfrac{1}{3} \div 10$ 5. $5 \dfrac{1}{4} \div 8 \dfrac{1}{2}$ 6. $\dfrac{8}{16} \div \dfrac{16}{8}$ 7. $4 \div 3 \dfrac{2}{3}$ 8. $\dfrac{2}{5} \div 5 \dfrac{6}{9}$ 9. $\dfrac{9}{13} \div 9$ 10. $\dfrac{11}{22} \div \dfrac{1}{2}$ 11. $2 \dfrac{9}{20} \div 5 \dfrac{2}{5}$ 12. $3 \dfrac{1}{2} \div 9 \dfrac{1}{2}$ 13. $5 \div 25$ 14. $\dfrac{10}{3} \div \dfrac{1}{6}$ 15. $\dfrac{13}{33} \div \dfrac{39}{3}$ 16. $100 \dfrac{1}{2} \div 10 \dfrac{5}{6}$

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/01%3A_Mathematical_Review-_Fractions/1.04%3A_Multiplying_Fractions.txt

Numbers written with decimals is another way of expressing fractions. However, decimals have a distinct differentiation with fractions in that decimals are based on 10. In that, one decimal place to the right of the whole number indicates tenths, two decimal places to the right of the whole number indicates hundredths, three decimal places to the right of the whole number indicates thousandths, etc. Example $1$ 0.1 = tenths place 1.01 = hundredths place 0.001 = thousandths place 1.01 = ten thousandths place Decimals can easily be written as fractions by using the number to the right of the decimal point as the numerator and then using a 10, 100, 1,000, 10,000, etc. as the denominator. Determining which “base-ten” number to use as the denominator is determined by the number of digits there are to the right of the decimal point. Example $2$ $\begin{array}{ll} 0.1 \rightarrow \dfrac{1}{10} & 1 \text { tenth } \ 0.01 \rightarrow \dfrac{1}{100} & 1 \text { hundredth } \ 0.001 \rightarrow \dfrac{1}{1,000} & 1 \text { thousandth } \ 0.0001 \rightarrow \dfrac{1}{10,000} & 1 \text { ten-thousandth } \end{array}$ Exercise 2.1 Write the following decimals as fractions and reduce if necessary. 1. 0.2 = 2. 0.103 = 3. 0.13 = 4. 0.02 = 5. 0.1234 = 6. 0.0023 = 7. 0.0101 = 8. 0.1010 = 9. 0.020 = 10. 0.0202 = 11. 0.1000 = 12. 0.4500 = Exercise 2.1.1 Write the following expressions as decimals and fractions. Decimal Fraction 7 tenths 1,000 ten-thousandths 475 thousandths 32 hundredths 12 thousandths 2,345 ten-thousandths 3 hundredths 10 thousandths 132 ten-thousandths 4,002 ten-thousandths Digits to the left of the decimal indicate a whole number. Whenever there is a whole number with a decimal fraction the expression is pronounced using “and.” Example: 12.3 = Twelve and three tenths = $12 \dfrac{3}{10}$ 100.07 = One hundred and seven hundredths = $100 \dfrac{7}{100}$ 3,005.023 = Three thousand five and twenty-three thousandths = $3,005 \dfrac{23}{1,000}$ Exercise 2.1.2 Write the following expressions as a decimal and a fraction. Remember to reduce if necessary. Decimal Fraction Two and five hundredths Thirteen and two hundred thousandths One thousand three and two ten-thousandths Fifty-five and fifty hundredths One and fourteen hundredth Eleven thousand four and twelve thousandths Ten and two tenths Four hundred one and four ten-thousandths Five thousand two hundred eight and one thousand ten-thousandths 2.02: Multiplying and Dividing Decimals Multiplying and dividing decimals is simple enough if you use a calculator. When multiplying decimals, there is no certain order you need to type the numbers in your calculator. Example $1$ 0.255 × 0.23 = 0.05865 25 × 35 = 875 100.5 × 12.75 = 1,281.375 Exercise 2.2 Multiply the following problems 1. $\begin{array}{r} 5 \ \times 0.35\ \hline \end{array}$ 2. $\begin{array}{r} 65 \ \times 0.2\ \hline \end{array}$ 3. $\begin{array}{l} 0.515 \ \times 0.15\ \hline \end{array}$ 4. $\begin{array}{l} 20.54 \ \times 5.01\ \hline \end{array}$ 5. $\begin{array}{l} 0.002 \ \times 1.07\ \hline \end{array}$ 6. $\begin{array}{r} 0.9 \ \times 0.8\ \hline \end{array}$ 7. $\begin{array}{r} 8.5 \ \times 0.2\ \hline \end{array}$ 8. $\begin{array}{r} 52 \ \times 0.11\ \hline \end{array}$ 9. $\begin{array}{r} 0.4 \ \times 0.04\ \hline \end{array}$ 10. $\begin{array}{r} 4.23 \ \times 2\ \hline \end{array}$ 11. $\begin{array}{r} 0.2 \ \times 0.45\ \hline \end{array}$ 12. $\begin{array}{r} 2.68 \ \times 0.298\ \hline \end{array}$ When dividing decimals, the denominator (or the divisor) is divided into the numerator (or the dividend). The resultant answer is termed the quotient. In the example below, 25 is divided into 125. On your calculator, you would type in the 125 first and then the 25. It is read as 125 divided by 25. Example $2$ $\begin{array}{ll} \dfrac{125}{25}= & 5 \ \dfrac{1.25}{25}= & 0.05 \ \dfrac{1.25}{0.25}= & 5 \end{array}$ Exercise 2.2.1 Divide the following problems. 1. $0.6 \div 5=$ 2. $28 \div 7=$ 3. $14 \div 20=$ 4. $0.54 \div 12=$ 5. $75 \div 40=$ 6. $1.44 \div 12=$ 7. $0.48 \div 2.4=$ 8. $156 \div 0.78=$

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/02%3A_Decimals/2.01%3A_Understanding_Decimals.txt

Rounding is another important process to understand and properly use mathematics. As we discussed in Section 2.1, decimal places can be carried out to the ten-thousandths place and further if needed. However, there is a practical rule to follow and in waterworks mathematics we seldom carry decimal places much further than the hundredths place, unless we are working in the area of water quality. The rule to follow is to “round” the decimal to the furthest decimal place in the question. Look at the examples below. Example \(1\) 2 × 2 = 4 Since both numbers you are multiplying are whole numbers, then you would leave the answer as a whole number. 2.0 × 2.0 = 4.0 Now, upon first glance, the answers may look like they are the same. After all, doesn’t 4 and 4.0 equal the same number? The short answer is yes. However, 4.0 is actually more accurate than 4. Why? Because 4.0 is rounded to the tenths place and is saying the value is no more than 4 and 0 tenths. When we “round” the first answer “4” can be 4.1, 4.2, 4.3, or 4.4. We don’t know, since the whole numbers are expressed as whole numbers and not round to the nearest tenth. Since both numbers being multiplied are rounded to the nearest tenth, then we round the answer to the nearest tenth. 2.0 × 2 = 4.0 This answer is also rounded to the nearest tenth since one of the numbers being multiplied is rounded to the nearest tenth. However, the second example is still the most accurate. Why? Now let’s look at how we round. The rule is simple. If the preceding number you are rounding to is </=4 (0, 1, 2, 3, or 4) you round down, which is to say you round to the preceding number. If the number is >/= 5 (5, 6, 7, 8, or 9), then you round up, which is to say the preceding number goes up by one. See the examples below. Example \(2\) Round to the nearest whole number 1.2 = 1 1.24 = 1 1.25 = 1 Since we are rounding to the whole number, we look at the tenths place or the number to the right of the place we are rounding to. In these examples the number is 2, which is </= 4. Round to the nearest tenths place 1.2 = 1.2 1.24 = 1.2 1.27 = 1.3 We now need to look at the hundredths place or the number to the right of the tenths place. Since there is no hundredths place in the first example, the number stays at 1.2. In the second example you would round down since the preceding number is </= 4 and in the third example, you would round up since the preceding number is >/= 5. Exercise 2.3 Round the following numbers Round to the nearest whole number. 1. 29.05 2. 135.9 3. 0.4 Round to the nearest tenth place. 1. 20.045 2. 0.98 3. 200.03 Round to the nearest hundredth place. 1. 1.234 2. 0.976 3. 345.095 Round to the nearest thousandth place. 1. 3 2. 1,367.0982 3. 0.9855 Did any of the questions above give you difficulty? Let’s look at number 5. The question said to round to the nearest tenth place. Therefore, we need to look at the preceding number or the hundredths place. The number was 0.98, so we need to look at the 8. Since 8 is >/= 5 we must round the number in the tenths place up. However, in this case the number to be rounded up is a 9. Look at the example below: 0.98 the 9 becomes 10, but since it is a 0.9, it becomes 1.0 What about number 10? In this question, you need to round a whole number (3) to the thousandth place. Therefore, you need to add zeros until you get to the thousandths place. See below: 3 = 3.000 In this text we will typically round to the nearest whole number, tenths, or hundredths places.

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/02%3A_Decimals/2.03%3A_Rounding.txt

Percentages and decimals are commonly used in waterworks mathematics. Whether you are working with financial budgets, chemical percent concentrations, or water quality results, decimals and percentages are used often. Therefore, knowing how to convert to percentages from decimals is important and vice versa. When expressing numbers as a percent they need to be whole numbers or decimals. Therefore, fractions must be converted first. Percent (%) simply means per hundred. Understanding that percent means per hundred indicates that 2 decimal places are involved. When a number needs to be converted to a percent you multiply the number by 100 and put a percent sign (%) at the end. Example $1$ The number 1 written as a percent is 1 × 100 = 100% The number 5 written as a percent is 5 × 100 = 500% When a decimal is written as a percent do the same thing. 1.4 × 100 = 40% Note that the decimal moves two places to the right. When a percent is written as a decimal, you simply divide the number by 100. Dividing by 100 moves the decimal two places to the left. Example $2$ If 100% is to be written as a number, divide by 100. $100 \% \div 100=1\nonumber$ $8.25 \% \div 100=0.0825\nonumber$ $2,500 \% \div 100=25\nonumber$ Exercise 3.1 Convert the following numbers to percentages and percentages to numbers (round all numbers to the nearest hundredth place. 1. 1 = 2. 30 = 3. 0.5 = 4. 0.75 = 5. 1.02 = 6. 35.5 = 7. 0.004 = 8. 5.005 = 9. 102% = 10. 2.3% = 11. 0.45% = 12. 1,570% = 13. 8% = 14. 0.9% = 15. 65% = 16. 12.5% = 3.02: Word Problems Word problems tend to give people some difficulty. Especially in problems where there is a lot of information that is not needed to solve the actual problem. However, most of the problems we deal with involve words. How much money did I pay in taxes last year? How many pounds of chemical do I need to add to this water supply? How many gallons of water were sold last month? What is the flow rate of water through that pipeline? What is the area of the filter bed? Yes, the questions posed above do not have any information to be able to solve for the answer, but these are some very common questions water operators are asked to solve. In word problems, there is always an underlying question that must be answered. Narrowing down the problem to the question you are trying to solve is an important step. Another important step is being able to pull out the information (numbers) in the question to help you solve for the answer. In word problems with percentages, there are a couple of things you should take note of. The word “is” should be treated as an equal (=) sign and the word “of” as a multiplication ($\times$) sign. You must also remember to convert the percent to a decimal prior to solving. 4.01: Solving Equations Equations are a vital component to solve many mathematical questions. In fact most of all water related mathematical questions would require the use of one if not several equations. An equation is a mathematical statement that both sides of an “equal sign” are in fact equal. Example $1$ $3 + 1 = 4$ or $5 - 3 = 4 - 2$ Mathematical equations involve solving for an unknown or a variable. A variable is typically represented with a letter. That “letter” is what you are trying to solve. Example $2$ $3+X=4$ What number must X be in order to make this equation correct? Obviously, the answer is 1. Now, this is a very simple example, but it will allow you to begin the process for solving more complex equations. How did you solve the example above? Did you simply look at the equation and intuitively know that the answer was 1? Or did you use some mathematical process to solve for the variable? Let’s break it down. Steps to solving equations; 1. Get the unknown or unknowns on one side of the equation. 2. Get the numbers on the other side of the equation. 3. Try and follow these helpful tips. 1. If the problem is an addition problem, you will need to subtract 2. If the problem is a subtraction problem, you will need to add 3. If the problem is a multiplication problem, you will need to divide 4. If the problem is a division problem, you will need to multiply Depending on the type of problem, this will involve adding, subtracting, multiplying, or dividing. Perhaps several steps will need to be done to solve for the variable. Since we will not be adding or subtracting in this course, we will focus on multiplication and division problems. If the variable is next to a fraction or directly next to a number, solving for the variable will require either multiplying or dividing. These next two examples are using multiplication and division to get the variable by itself. In order to prevent confusion, the variable of choice will be something other than an “X.” Example $3$ $2N=10$ What multiplied by 2 equals 10? In order to solve for “N” you will need to divide both sides of the equation by 2. $\dfrac{2N}{2}=10$ By dividing the left side of the equation by 2, you isolate the variable. However, since you divided one side of the equation by a number you must do the same to the other side of the equation. $N=\dfrac{10}{2}$ $N=5$ In this next example, a fraction of a variable will equal a number. Example $4$ $\dfrac{2}{3} N=14$ In order to isolate the variable in this type of problem, you will need to multiply and divided. First, divide both sides of the equation by 2 and then multiply both sides of the equation by 3. $\dfrac{2}{(2) 3} N=\dfrac{14}{2}$ The two cancels out on the left side of the equation leaving N over 3 and 14 divided by 2 becomes 7. $\dfrac{N}{3}=7$ Now, multiply both sides of the equation by 3. $\dfrac{(3) N}{3}=7 \times 3$ Here, the 3 cancels out on the left and the right side of the equation becomes 21, which is the answer. $N=21$ How can you prove (or show) that 21 is the correct answer in the above example. Exercise 4.1 1. $2 X=10$ 2. $3 N=15$ 3. $\dfrac{3}{4} G=9$ 4. $4 H+2=10$ 5. $\dfrac{1}{5} J+4=5$ 6. $13=\dfrac{3}{6} K-1$ 7. $3 B-5=2 B+8$ 8. $10 C-7=3 C+14$ 9. $\dfrac{4}{3} S-3=5$ 10. $14=2F+2$ 11. $7 X+2=9 X-10$ 12. $15=5+\dfrac{2}{5} P$

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/03%3A_Percentages/3.01%3A_Expressing_Numbers_as_Percentages.txt

Solving ratios and proportions is similar to the previous two exercises. It is simply just looking at the question a little differently. Instead of looking at it as numbers we will assign UNITS (or items) to the numbers, for example, 3 valves to 6 valves or 3 hours to 5 hours. However, the real comparisons of interest will be discussed in the next section when we compare different UNITS to each other, for example, 40 hours to 1 week, or 12 inches to 1 foot. Example $1$ $\dfrac{2}{3}=\dfrac{F}{9}\nonumber$ You can read this as, 2 is to 3 as F is to 9. In order to solve the above ratio or proportion is by cross multiplying. $9 \times 2=3 \times F \nonumber$ This would equate to $18=3 F \nonumber$ Then using the method as previously used in the Equation Section, you would divide both sides of the equation by 3. Three would then cancel on the right side of the equation isolating the variable and 18 divided by 3 would give you 6. Therefore, F equals 6. $\dfrac{18}{3}=\dfrac{3 F}{3} \quad \rightarrow \quad 6=F \nonumber$ Exercise 4.2 1. $\dfrac{D}{7}=\dfrac{27}{9}$ 2. $\dfrac{28}{L}=\dfrac{32}{8}$ 3. $\dfrac{4}{8}=\dfrac{J}{64}$ 4. $\dfrac{H}{5}=\dfrac{28}{70}$ 5. $\dfrac{K}{100}=\dfrac{1}{3}$ 6. $\dfrac{L}{12}=\dfrac{12}{3}$ 7. $\dfrac{9}{4}=\dfrac{K}{12}$ 8. $\dfrac{7}{F}=\dfrac{5}{15}$ 9. $\dfrac{H}{3}=\dfrac{20}{6}$ 10. $\dfrac{2}{5}=\dfrac{Q}{35}$ 11. $\dfrac{13}{F}=\dfrac{32}{64}$ 12. $\dfrac{1}{7}=\dfrac{11}{J}$ Not all proportional problems are exactly as they seem. The previous problems were directly proportional and can be solved with relative ease. However, sometimes you will encounter indirectly proportional or more properly termed “inversely” proportional. Example $2$ It takes 3 employees to flush 8 hydrants in 6 hours. How long would it take 5 employees to do the same job? Solution If you attempt to solve this problem as if it were directly proportional it would look like. $\dfrac{3}{6}=\dfrac{5}{W} \quad \rightarrow \quad W=\dfrac{30}{3} \quad \rightarrow \quad W=10 \nonumber$ By this result it would take 5 employees 4 hours longer to do the same job. Inversely proportional problems need to be solved as follows. It is the product of the values not the ratio that you need to equate. 3 employees × 6 hours = 5 employees x W hours $\begin{array}{l} 18=5W \ W=\dfrac{18}{5} \ W=3.6 \text { hours } \end{array} \nonumber$ Exercise 4.2.1 1. A safety catalog sells dust masks. They are $4.50 per dozen. How much would 4 dust masks cost? 2. An operator conducted a laboratory experiment by adding 1.5 pounds of chlorine to 5 gallons of water to get a certain chlorine dosage. If the operator wanted to disinfect 1,200 gallons of water to the same dosage, how many pounds of chlorine would she need? 3. Six water utility operators were able to exercise 75 valves in one work week. If 9 operators were assigned to do the same task, how long would it take them? (Assume 34 hours equates to a work week) In the previous problem, you ended up with a fraction (expressed as a decimal) of an hour. What would be a better way to express this answer? 1. A water utility needs to install 2,375 feet of 16” diameter pipe. The pipe costs$25.80 per foot. How much will all the pipe cost? 2. In the problem above, the pipe is manufactured in 20 foot sections. How many sections would need to be purchased? 3. A water storage tank needs to be recoated. A contractor gave an estimate that it would take 5 of his employees a total of 39 hours to complete the job. How sooner can the job be completed if 8 employees were to do the work? In word problems with percentages, the first thing is to convert the percent to a decimal. Then, view the word “of” as a multiplication sign and the word “is” as an equals sign. Then, solve the problem Example $3$ 10% of 100 is 10% × 100 = 0.10 × 100 = 10 Exercise 4.2.2 Solve the following percent problems. 1. 30 is 20% of what number? 2. 10 is 45% of what number? 3. 12% of is 84. 4. What percent of 75 is 225? 5. 56% of is 182. 6. 35 is what percent of 500? _________________ 7. 100% of 2,000 is ______________ 8. What percent of 40 is 10? ____________ Word problems give people fits! However, most of the problems that present themselves in practical situations are in fact word problems, we just don’t always think of them that way. For example, if you are buying something from the store and you want to figure out how much the tax will be on a certain item, you probably just multiply the cost of the item by the sales tax. You can though look at this problem as a word problem. Exercise 4.2.3 Solve the following word problems. 1. A water utility executive earned \$85,000 last year and received a 22% bonus. How much was her bonus? 2. A worker can paint a fire hydrant in ½ hour. How many hydrants can she paint in 4 hours? 3. A 5 gallon jug of bottled water is labeled 60% spring water. How many gallons in the jug is spring water? 4. On a state certification treatment exam you must score at least 70% to pass. If there are 65 questions on the test how many must you get correct to pass?

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/04%3A_Equations_and_Word_Problems/4.02%3A_Ratios_and_Proportions.txt

“Units” are the single most important component of many mathematical problems especially in the waterworks industry. If you are reporting a flow rate of 1,000, what does this mean? 1,000 gallons per minute? 1,000 cubic feet per second? Or, 1,000 acre feet per year? It is strongly recommended that you get in the habit of writing down the units for all the problems you are solving. Most of the problem solving in waterworks mathematics requires the conversion of units. Cfs gpm MGD AFY Therefore, Unit Dimensional Analysis (UDA) is the key to solving a majority of water related mathematical problems. UDA is the process of converting units of one type (e.g. gallons) to another similar type (e.g. cubic feet). Setting up your UDA problem is the most important step conversion problems. By “stacking” your units you create a visual representation of the problem where units can be canceled. This cancellation of units is very similar to cross canceling or reducing of fractions. Example $1$ Convert seconds to days using UDA $\dfrac{\text {sec} }{1} \times \dfrac{\text {min} }{\text {sec} } \times \dfrac{\text{hour}}{\min } \times \dfrac{\text { day }}{\text { hour }} \nonumber$ Solution If we break the problem up into segments you can see how the canceling of units occurs. $\dfrac{\not {\text {sec}}}{1} \times \frac{\min }{\not {\text {sec}}}=\min \nonumber$ In the above example, if we just do the first step you can see that canceling seconds will yield minutes as the result. By continuing the same process you can end up with the unit the question is asking. $\dfrac{\not {\sec}}{1} \times \dfrac{\not {\min}}{\not {\sec}}=\dfrac {\not {\text {hour}}}{\not {\min }} \times \dfrac{\text {day}}{\not {\text {hour}}} = \text {day} \nonumber$ The reason seconds is set up over a “1” is because it is the units you are wanting to convert from and remember anything over 1 is that value. Multiple units can be converted in a single problem too. However, convert one unit at a time. A common waterworks mathematics problem is the conversion from cfs to gpm. Cubic feet needs to be converted to gallons and seconds needs to be converted to minutes. Example $2$ Convert cfs to gpm. $\dfrac{\text{cf}}{\text{sec}} \rightarrow \dfrac{\text{gal}}{\text{min}} \nonumber$ Solution An important thing to note is that you will be converting “like” units. This means that you will be converting cubic feet to gallons which are both a measurement of volume and converting seconds to minutes which are both a measurement of time. There are two conversion factors that need to be used to perform this conversion. You need to ask yourself…How many seconds are in a minute? How many gallons are in a cubic foot? There are 60 seconds in every minute. There are 7.48 gallons in every cubic foot. $\dfrac{\text{lcf}}{\sec } \times \dfrac{60 \text{sec}}{\min } \nonumber$ The expression 60 sec per minute is a conversion factor that is an equality. The conversion factor is deliberately written with the 60 sec on top of the equality because it needs to cancel the unit sec from the 1 cfs. $\dfrac{1 \text{cf}}{\not {\sec}} \times \dfrac{60 \not{\sec} }{\min }=\dfrac{60 \text{cf}}{\min } \nonumber$ Since the sec cancel we end up with cubic feet per minute (cfm). Now let’s look at converting cubic feet to gallons. Remember that there are 7.48 gallons in every cubic foot. $\dfrac{1 \text{cf}}{\sec } \times \dfrac{7.48 \text{gal}}{\text{cf}} = \dfrac{1\not{\text{cf}}}{\sec} \times \dfrac{7.48 \text{gal}}{\not{\text{cf}}}=\dfrac{7.48 \text{gal}}{\sec} \nonumber$ If you combine both of the examples above you can see how cfs is converted to gpm. $\dfrac{1\not{\text{cf}}}{\not{\sec}} \times \dfrac{60 \not {\sec}}{\min } \times \dfrac{7.48 \text{gal}}{\not{\text{cf}}}=\dfrac{448.8 \text{gal}}{\min } \nonumber$ Exercise 5.1 Solve the following problems using UDA 1. Convert 5 cfs to gpm. 2. Convert 1,500 gpm to cfs. 3. Convert 4 MGD to gpm. 4. Convert 2.5 cfs to MGD. 5. Convert 7 fps to mph. 6. A hose is flowing at a rate of 1.5 cfs. How many gallons will flow through it in one minute? 7. A well pumps 2,000 gallons per minute. How many million gallons of water will it pump in one day? 8. A water utility sold 10 million gallons of water. They need to report this in one hundred cubic feet (CCF or HCF). How many HCF is this? 9. A water utility operator is filling up a storage tank at a rate of 1,000 gallons per minute. How long will it take until the tank has 1.5 MG of water? 10. Water is moving through a pipe at a velocity if 5.75 feet per second. Express the velocity in miles per hour. 11. Last year a water utility delivered 2.35 million gallons per day. How many acre feet did they deliver in one year? 12. A water tank was being drained at a rate of 750 gallons per minute. If the tank holds 5 MG of water, how long will it take for the tank until the tank is empty? (Express your answer as Days, Hours, Minutes – ex 2 days, 3 hours, and 10 minutes)

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/05%3A_Unit_Dimensional_Analysis/5.1%3A_Units.txt

In the waterworks industry geometric shapes are prevalent. For example, a pipe is a cylinder with the opening of a circle, a sedimentation basin can be a rectangle, and an aqueduct might be a trapezoid. These are a few of the shapes that we will cover in this text. It is important to understand how to work with these shapes to be able to calculate areas, volumes, perimeters, and circumferences. We will first look at geometric shapes and how to calculate the corresponding area of these shapes. The answer when determining the area of a geometric shape should always be given in square feet (sqft or ft\(^2\)). Other units can be used such as, square meters or square inches, but these are not typically used in the waterworks industry. Remember though that the units you are given in a question (or in “real life” for that matter, may not be the units you need to calculate square feet. Therefore, you should always convert the “given units” to feet before calculating the area. The first shape we will look at is the CIRCLE. Pipes are the backbone to water distribution systems and can also be found in treatment plants. Pipe lines carry raw water to the treatment plant, transmission lines can carry water from treatment plants to storage tanks, and distribution pipe lines delivery water to customers. 06: Geometric Shapes Circle Area of a circle = $0.785 \times D^2$ Typically, you will know the diameter of a circle, for example the diameter of a pipe or a storage tank. You may have learned the following formula ($\pi \times r^{2}$) for calculating the area of a circle. However, in this text we will only use the previous formula. Both formulas work, but in the water industry diameters are most commonly used. Much of the time you will be asked to calculate the area of the opening of a pipe. However, the unit given to you will typically be given in inches. There are two ways to go about solving this type of problem. Example $1$ What is the area of a 12” diameter pipe? Solution If you were to plug 12” into the formula (0.785 \times D^2\) you would end up with square inches and then you would most likely need to then convert to square feet. So, the easiest way to solve all area problems where “feet” are not given is to convert to feet first and then plug the numbers into the formula. A 12” diameter pipe equals a 1 foot diameter pipe. $\dfrac{12 \not{\text { inches }}}{1} \times \dfrac{1 \text { foot }}{12 \not{\text { inches }}}=1 \text { foot } \nonumber$ By converting to feet before starting the problem you will avoid getting into units you are not familiar with. Rectangles Area of a rectangle = $L \times W$ Rectangles are common shapes of storage reservoirs, sedimentation basins, and even room in an office. Calculating the area for these types of structures is simple if you know how the length and width of the structure. Remember, the area of a square is calculated the same way. These types of dimensions are typically given in feet. Trapezoid Area of a trapezoid = $\dfrac{b1+b2}{2} \times H$ Trapezoids are not as common as circles, rectangles, and squares, but they are still found in the waterworks industry. Typically open channels and aqueducts are shaped like a trapezoid. In calculating the area of a trapezoid, you need to know the width across the aqueduct and the height of the water level. Now the width changes from the bottom of the trapezoid to the top. For example, the distance across the bottom of the trapezoid is a shorter distance then it is at the top of the trapezoid. The other point that needs to be addressed is the distance across the top of the trapezoid that is needed is the distance across the top of the water level. See the diagram below for an example of the base 1. Once you know the distance across the trapezoid at the water level, then add it to the distance across the bottom of the trapezoid and divide that number by 2. Doing this finds the average distance across the trapezoid. Multiply this number by the height of the water level and you know have the area of the trapezoid. Exercise 6.1 Calculate the following areas. 1. What is the area of a circle with a 2 foot diameter? 2. What is the area of a 36” diameter pipe? 3. What is the area of a sedimentation basin that is 30 feet wide and 10 feet deep? 4. What is the area of an aqueduct that is 5 feet across the bottom, 10 feet across the top and 7 feet deep? 5. The roof on an above ground storage tank has a 130 foot diameter. What is the area? 6. A filter is 25 feet long and 20 feet wide. What is the area? 7. A water aqueduct is 10 feet wide at the bottom and 20 feet wide at the top. If it is 20 feet deep what is the area?

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/06%3A_Geometric_Shapes/6.01%3A_Areas.txt

Cylinder Volume of a cylinder = $0.785 \times D^{2} \times H$ The volume of a cylinder uses the area formula of a circle with the addition of a third dimension. Notice that a cylinder can have either a depth or a height. They are one and the same. It all depends on your perspective. In fact all 3 dimensional structures can have a depth or a height. Rectangle Volume of a rectangle = $L \times W \times H$ Trapezoid Volume of a trapezoid = $\dfrac{b1+b2}{2} \times H \times L$ There is something to keep in mind when calculating volumes. Most units in waterworks are given in “feet.” The length of pipe, the height of water tanks, the depths of aqueducts are all typically measured in feet. Therefore, calculating the volume for these geometric shapes result in cubic feet as the unit of measure. However, sometimes measurements are given in “inches” and will need to be converted to feet before solving a problem. Exercise 6.2 Solve the following 1. What is the area of a circle with a 10 foot diameter? 2. What is the area of a circle with a 10 inch diameter? 3. What is the area of a rectangle with a depth of 10 feet and a width of 20 feet? 4. What is the area of a trapezoid that has a distance across the base of 5 feet and a distance across the top of the water level of 7 feet. The water depth is 4 feet. 5. Calculate the volume of a pipe that has a 12” diameter and is 10 feet long. 6. How many gallons of water can fit in a storage tank that is 40 feet tall and has a 90 foot diameter? (Remember one cubic foot equals 7.48 gallons) 7. A rectangular basin is 100 feet long, 40 feet wide and has a depth of 25 feet. If the water level is 3 feet from the top, how much water is in the basin? 8. A one mile long water aqueduct is 10 feet deep and is half full. The width across the water level is 7 feet and the width at the base is 5 feet. How much water is in the aqueduct? (Remember that one mile equals 5,280 feet) 9. A 75 foot tall water tank is ¾ full and has a 30 foot diameter. How many gallons of water are in it? 10. What is the capacity of a water basin that is 200 feet long, 40 feet wide, and 30 feet deep? 11. A water tank is being emptied at a rate of 1 foot per hour. If the tank has a diameter of 100 feet, how many gallons will be emptied in 4 hours? 12. A reservoir with the following dimensions (75 feet long, 20 feet wide, 10 feet deep) is 35% empty. How many gallons of water are in the reservoir? 6.03: Circumference The last geometric shape formula we will look at is the circumference of a cylinder. The circumference is the distance around a closed curve. It is the distance around the length around a circle. The importance of this formula in waterworks mathematics displays itself in questions regarding the painting or coating of a cylinder. The picture below illustrates the circumference. If you “slice” open a cylinder and unravel it, it becomes a rectangle. The length of this rectangle is the circumference of the cylinder. In order to calculate the surface area of a cylinder, use the following formula. Area of a cylinder = $H \times(\text { Diameter } \times \pi)$ Where ($\text { Diameter } \times \pi$) is the length around the cylinder. Exercises 6.3 Solve the following 1. What is the area of the wall of a 20 ft tall tank with a 30 ft diameter? 2. What is the area of the walls of a 1,000 ft section of 24” diameter pipe? 3. You have been asked to calculate how many gallons of paint would be needed to paint a 30 ft tall tank with a 100 ft diameter. You need to paint the inside roof, floor, and walls. One gallon of paint covers approximately 200 ft2. How many gallons of paint are needed?

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/06%3A_Geometric_Shapes/6.02%3A_Volumes.txt

Hydraulics is a fundamental theory in waterworks mathematics. Hydraulics involves the mechanical properties of liquids. In this text we look at two different hydraulic principles, pressure and flow. 07: Water Hydraulics Pressure is related to the vertical distance from the surface of water to a reference point somewhere below the water surface typically expressed in feet. For example, a water storage tank has a certain water level inside of it. The reference point below could be a water faucet a certain distance in feet below the water level. This distance in feet is the head pressure (in feet). The other common unit for pressure is POUNDS PER SQUARE INCH, (psi). You can convert back and forth between feet and pounds per square inch using one of the following conversion factors. $1 \text { foot }=0.433 \mathrm{psi} \quad \text { or } \quad 1 \mathrm{psi}=2.31 \text { feet } \nonumber$ To stay consistent with UDA, view the following conversion factors as $\dfrac{1 \text { foot }}{0.433 \text { psi }} \quad \text { or } \quad \dfrac{1 \text { psi }}{2.31 \text { feet }} \nonumber$ Remember, as with all conversion factors, these can be written as the inverse. $\dfrac{0.433 \mathrm{psi}}{1 \mathrm{foot}} \quad \text { or } \quad \dfrac{2.31 \text { feet }}{1 \mathrm{psi}} \nonumber$ Example $1$ 1. Assume both cylinders above are filled with water, which one has a greater pressure at the base of it? 2. What is the pressure at the base of each cylinder? Solution 1. The answer is neither! The pressure at the base of each cylinder is the same because the height of the water is the same. 2. $\dfrac{30 \text { feet }}{1} \times \dfrac{1 \mathrm{psi}}{2.31 \mathrm{feet}}=12.98 \mathrm{psi}$ or (if you round) $13 \mathrm{psi}$ Exercise 7.1 Calculate the following pressure problems 1. What is the pressure in psi at the bottom of a 30 foot tall tank if it is full? 2. What is the pressure in feet if the psi is 130? 3. A storage tank is 45 feet tall and half full. What is the pressure in psi? 4. A water tank sits on a 50 foot hill and is 25 feet tall. Assuming the tank is full, what is the pressure in psi at the bottom of the hill? 5. A fire hydrant was hit and water is spraying up approximately 75 feet. What is the approximate pressure in psi? 7.02: Force Pressure is the force applied over a specific area. It is the weight of water expressed as pounds divided by the area expressed as inches squared (in$^2$). Therefore, the resulting unit is pounds per square inch (psi). However, in the previous section we looked at pressure based on the height or elevation of a column of water and compared it against a conversion factor. Recall the following conversion factors: 0.433 psi = 1 foot and 1 psi = 2.31 feet Let’s take a look at what 1 psi is actually saying. One (1) pound of force per square inch of surface area. Therefore, if you have one (1) pound of water and place it on one (1) square inch of area, the resulting pressure would be 1 psi. The definition of force can be explained as the push or pull which an object can change the velocity of the object on which it is applied. If the pressure is known and the area of which the pressure is being applied, the force can be calculated. See the example below: A pressure of 100 psi exerts how much force against an area of 1 in$^2$? In this example, there is $\dfrac{100 \text {lbs}}{\text{in}^{2}} \times \text{in}^{2} \nonumber$ This would equate to 100 lbs of force because the in$^2$ would cancel. This says that 100 pounds of force is being exerted. Another example of calculating the force in pounds would be by calculating the entire volume of water and then converting to the water of the volume of water. Look at the example below. If a tank with a 100 ft diameter and is 20 ft tall, what is the force at the bottom? In this example, the dimensions of the tank can be used to calculate the volume of water. $V=0.785 \times(100 \mathrm{ft}) 2 \times 20 \mathrm{ft} \times 7.48=1,174,360 \mathrm{gal} \nonumber$ This volume can now be converted to pounds. $1,174,360 \text { gal } \times 8.34 \text { lbs/gal }=9,794,162 \text { lbs } \nonumber$ This is the force exerted. Exercise 7.2 1. Calculate the force exerted on a 6” diameter valve with a pressure of 90 psi. 2. What is the force at the base of a 100 ft tall tower filled with water and a diameter of 10 ft? 3. A water tank is 50 feet tall and half full. If the diameter is 75 feet, what is the force exerted at the bottom? 4. A fire hydrant with a 2 ½” opening has a pressure of 130 psi. What is the corresponding force?

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/07%3A_Water_Hydraulics/7.01%3A_Pressure.txt

Flow is the path that a certain liquid (water) takes for a specific time. It is commonly referred to as Flow Rate. A garden hose, a water main, an aqueduct, a gutter, have flow rates. You must know the area of the vessel or container that is flowing the liquid and you must also know the velocity that the liquid is moving. Flow Rate is simply expressed as volume over time. $\dfrac{\text { Volume }}{\text { Time }} \nonumber$ The volume can be gallons, million gallons, cubic feet or any other volume unit. The time can be any time such as, seconds, minutes, hours, etc. However, when solving Flow Rate ALWAYS use the UNTIS – CUBIC FEET PER SECOND, where Q represents Flow Rate. Expressed as $\mathrm{Q}=\dfrac{\text { Volume }}{\text { Time }}=\dfrac{\text { cubic feet }}{\text { second }} \nonumber$ In order to calculate a Flow Rate, you need to know the Area of the vessel that the liquid is traveling through and the Velocity in which the liquid is traveling. The formula for Flow Rate is $\mathrm{Q}=\mathrm{A} \times \mathrm{V} \nonumber$ Where the Area is expressed as – $0.785 \times D^2$ (for circles) - $L \times H$ (for rectangles) and $\dfrac{b 1+b 2}{2} \times H$ (for trapezoids) And Where Velocity is expressed as – $\dfrac{\text { Distance }}{\text { Time }}$ The UNITS for AREA should always be in SQUARE FEET and the UNITS for VELOCITY should always be in FEET PER SECOND. Therefore, the equation should look like this $\dfrac{\text { cubic }}{\text { feet }}=\dfrac{\mathrm{ft}^{2}}{1} \times \dfrac{\mathrm{ft}}{\text { second }} \quad \rightarrow \quad \dfrac{\mathrm{ft} \times \mathrm{ft} \times \mathrm{ft}}{\text { second }}=\dfrac{\mathrm{ft} \times \mathrm{ft}}{1} \times \dfrac{\mathrm{ft}}{\text { second }} \nonumber$ If you like using the “Pie Wheel” the following can be applied for Flow Rate. Exercise 7.3 1. What is the pressure in pounds per square inch at the bottom of a 45 foot tall water storage tank? 2. An 80 foot tall standpipe is ¾ full. What is the pressure in psi at the bottom? 3. A 30 foot water tank has a pressure gauge installed 2 feet from the bottom of the tank. If the pressure gauge reads 11 psi, what is the level in the tank? 4. A 12” pipeline is flowing water at a velocity of 3.5 fps. What is the corresponding flow rate? 5. A 36” diameter pipe is flowing water at a velocity of 5 fps. How many gallons of water will flow through it in 2 hours? 6. An 18” pipe is flowing 1,500 gpm. What is the velocity? 7. What is the area of a box culvert that is flowing 4.5 MGD at a velocity of 2.45 fps? 8. An 8” diameter pipe is flowing water at a velocity of 7.65 fps. What is the flow rate in gallons per minute? 9. A 28 foot tall water tank is sitting on a 75 foot tall hill. What is the pressure in a home at the bottom of the hill? (Assume the pressure gauge is 3 feet from the bottom of the home and the tank is full) 10. What is the velocity through a 20” diameter pipe that flows 2.5 MGD? 11. A home that is receiving water from a water tank that is on top of a 115 foot hill has a pressure of 57 psi. What is the water level in the tank? 12. What is the area of a pipe that flows 2,550 gpm at a velocity of 5 fps?

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/07%3A_Water_Hydraulics/7.03%3A_Flow_Rate.txt

One of the most common and useful formulas in waterworks mathematics is one in which you use to calculate the amount of chemical needed to add to water. It is commonly known as the Pound Formula. The “pound” formula, because it is a calculation for the weight of a chemical that is being added to water. Typically this chemical is chorine or a chlorine related compound. However, it can be also used to calculate alum, ferric chloride, or any other type of chemical dosage. Wastewater has several treatment processes to help breakdown the sewage as it moves through a wastewater treatment plant. In addition to adding chemicals, bacteria and microorganisms are used to establish adequate balances during the treatment process to remove organic material and reduce ammonia. 08: Chemical Dosage Analysis and Waste Water Treatment When solving the “Pound” formula the following two formulas are used. The first formula is used when you are calculating chemical dosage on a volume of water, for example a tank, reservoir, or pipeline. $\dfrac{\mathrm{MG}}{1} \times \dfrac{8.34 \mathrm{lbs}}{\mathrm{gal}} \times \dfrac{\text { parts }}{\text { millionparts }}=\dfrac{\mathrm{lbs}}{1} \nonumber$ The second formula is used when you are calculating chemical dosage on a flow rate, for example through a pipeline, in a channel, or through a treatment facility. $\dfrac{\mathrm{MG}}{\mathrm{D}} \times \dfrac{8.34 \mathrm{lbs}}{\mathrm{gal}} \times \dfrac{\text { parts }}{\text { millionparts }}=\dfrac{\mathrm{lbs}}{\mathrm{day}} \nonumber$ Note that the only difference between the two formulas is the unit for time. It is also important to note that the formula uses specific units for volume and flow…MILLION GALLONS and MILLION GALLONS PER DAY. Therefore if you are given a volume in cubic feet, gallons, acre-feet or some other unit, you must convert to million gallons. The same holds true for flow rates. If you are given a flow rate in cubic feet per second, gallons per minute, acre-feet per year or some other unit, you must convert to million gallons per day. The following charts are helpful in illustrating how to use the pound formula. Look at the horizontal line as a division sign. Anything above the line is divided by anything below the line. Everything below the line (that are next to each other) would be multiplied together. Here is an example. Example $1$ MG(D) and ppm are the two variables below the line. Therefore, they would be multiplied by each other and multiplied by 8.34 lbs./gallon. Since lbs or lbs/day are above the line then you would divide the product of the values below the line. In this class we will assume that any chemical we are using is in its pure form. In other words there is no adjustment for a lesser concentration form of a chemical. When chlorine is used, it is 100% chlorine. In addition to drinking water treatment, wastewater treatment uses this same formula to calculate the chemical dosage needed to add certain chemicals to wastewater. Also, this formula is used to determine the amount of “waste” present in wastewater. A common way to measure the amount of organic waste is by the Biochemcial Oxygen Demand (BOD) test. Wastewater has a large amount of organic material that would put a certain demand on an aquatic system by depleting the available oxygen. The results of the test are typically expressed as mg/L or ppm and can be used in the “pound formula.” The following questions cover both drinking water and wastewater treatment processes. Exercises 8.1 1. How many pounds of chlorine are needed to dose 1 MG of water to 2 ppm? 2. How many pounds of chlorine are needed to dose 2,200,000 gallons of water to a concentration of 3.5 mg/L? 3. Dry Alum is added at a rate of 150 lb/day in a treatment plant operating at a rate of 16 MGD. What is the dosage in milligrams per liter? 4. How many gallons of water can be treated to a dosage of 10 ppm with 150 pounds of chlorine? 5. A wastewater treatment plant has a primary tank that can hold 2.5 MG. If the BOD test results are 450 mg/L, how many pounds of BOD are in the tank? 6. An operator added 75 pounds of chlorine to a water storage tank that has a 100 foot diameter and is 30 feet tall. The tank was only half full. What was the dosage? 7. A wastewater treatment plant treats 37,500 lbs of BOD per day. If the average daily flow is 8 MGD, what is the BOD concentration? 8. A well is flowing at a rate of 1,600 gpm and requires a dosage of 0.5 mg/L. How pounds of chlorine are needed per day? 9. An aeration tank receives a flow rate of 4,500 gpm. If the BOD concentration is 210mg/L, how many pounds of BOD are loading the aeration tank? 10. A treatment plant operates at a rated capacity of 15 MGD and maintains a constant 1.25 mg/L chlorine dosage. How many pounds of chlorine are needed per year? 11. In question 10, what is the annual budget for chlorine if the cost is \$1.65 per pound? 12. A wastewater treatment plant receives an average daily flow of 9.5 MGD. If the BOD test results are 320 mg/L, how many pounds of BOD does the treatment plant receive in a single day? 13. A water tank has a 150 foot diameter and is 35 feet tall. If 200 pounds of chlorine were added to it, what is the dosage? 14. How pounds of ferric chloride are needed to treat a basin that is 120 feet long, 30 feet wide, and 15 feet deep to a dosage of 3.25 mg/L?

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/08%3A_Chemical_Dosage_Analysis_and_Waste_Water_Treatment/8.01%3A_The_Pound_Formula.txt

Wastewater treatment relies on a biological process to treat the large amounts of organic material found in sewage. Bacteria consume the organic material (measured as BOD) and thus removes it from the wastewater. BOD can be thought of as food available to the bacteria. The amount of bacteria in the system can also be measured by a test called the Mixed Liquor Suspended Solids (MLSS). The ratio of how much food (BOD) in pounds is available to the population of microorganisms (MLSS) in pounds, is critical to the proper operation of a conventional wastewater treatment plant. This ratio is a baseline to determine how much food a single pound of organisms will eat every day. In aerobic wastewater treatment, operators supply bacteria with air in aeration tanks, so they can breathe. Typically, there is food available in the incoming wastewater for the bacteria. Under these conditions the microorganisms thrive and actually grow their population. If operators did not periodically “waste” the excess microorganisms from the system the MLSS would become too high and alter the F/M ratio. To calculate the Food to Microorganism ratio (F/M) we need to determine the amount of BOD in pounds, being sent to through the treatment system as well as the amount of available MLSS in pounds, in the system. The equation for F/M is: F/M = Pounds of BOD per day/Pounds of MLSS in tanks Typical Food to Microorganism ratios are between 0.2 and 0.5. A low F/M ratio means there are many microorganisms and a limited food supply. Conversely, a high F/M ratio means there is much more food available compared to microorganisms. Therefore, a very high or low ratio would result in a dispersed floc that will not settle well in the secondary clarifier. Exercise 8.2 1. A wastewater treatment plant receives an average flow of 5 MGD and the influent BOD is 260 mg/L. If the MLSS test shows there are 1,800 mg/L in the aeration tank that has a volume of 1.5 MG, what is the F/M ratio? 2. The primary effluent flow of wastewater treatment plant is 3.8 MGD and has a BOD concentration of 295 mg/L. The aeration tank is 150 feet long, 10 feet wide, and 8 feet deep. What is the F/M ratio if the MLSS is found to 2,600 mg/L? Influent BOD = 425 mg/L Primary Effluent BOD = 272 mg/L MLSS = 2,100 mg/L Aeration Volume = 2,890,000 gallons 8.03: Mean Cell Residence Time (MCRT) As we just learned with the F/M ratio, bacteria and microorganisms are essential to a properly functioning wastewater treatment plant. Another operational control parameter is the mean cell residence time (MCRT). This estimates how long a single bacteria or microorganism stays in the treatment process. The treatment process takes a certain amount of time to effectively remove the organic material and reduce the high amounts of ammonia. If the MCRT is to low then treatment will be insufficient. If the MCRT is too high then there is excess MLSS in the system which adds to the cost of operation. The equation to find out the MCRT is based on how much MLSS is in the system and how much MLSS is leaving the system through wasting. There are other equations and terms very similar to MCRT such as the Solids Retention Time (SRT). Some textbooks include the pounds of solids available in the secondary clarifiers as well as the final effluent suspended solids that are leaving the system. For this introductory class we will use the following equation: MCRT = Lbs under aeration/Lbs per day wasted The pounds under aeration is exactly the same as in determining the “M” in the F/M ratio. To determine the pounds wasted we need to know the flow rate of the waste activated sludge (WAS) and the concentration. Most treatment plants waste from the return activated sludge (RAS). The RAS is the microorganisms that have been settled out in a secondary clarifier. Therefore, the concentration of RAS is typically higher than MLSS. The MCRT will depend on the type of wastewater treatment system. Extended air plants will generally have MCRTs greater than 30 days. Conventional activated sludge plants generally have MCRTs between 5 to 10 days. Biological nutrient removal plants typically operate with a MCRT between 12 and 20 days, and high rate oxygen plants between 1 and 3 days. However, it is important to note that there are plenty of case studies showing plants operating outside these ranges while still achieving optimal treatment. Each plant is different and will develop their own optimal operating range. Exercise 8.3 1. A wastewater treatment plant has a total of 35,000 lbs of MLSS and has 2,900 lbs/day leaving the system. What is the MCRT in days? Influent flow = 10.5 MGD Primary Effluent BOD = 285 mg/L Aeration Volume = 5 MG MLSS = 2,280 mg/L WAS Q = 115 gpm WAS Conc. = 8,110 mg/L 1. An aeration tank has a volume of 375,000 gallons. The MLSS test results show there is 2,860 mg/L in the aeration tank. If a total of 2,100 lbs/day are wasted from the system, what is the MCRT of the facility?

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/08%3A_Chemical_Dosage_Analysis_and_Waste_Water_Treatment/8.02%3A_Food_to_Microorganism_Ratio.txt

Detention Time is the amount of time it takes for a molecule of water to travel a certain distance. In a sedimentation basin it is the time it takes for a particle to travel across the basin. Water treatment operators calculate detention times for settling basins, flocculation basins, or rapid mixing chambers. The term “Contact Time” can also be applied using this formula. Contact Time is not to be confused with CT (Concentration Time). Contact Time is best described as the time a certain chemical is in contact with water. For instance, if you add chlorine to a water supply you can ask yourself “how long is it in contact with the water before a customer drinks the water?” For reference, Detention Times are commonly expressed in hours. However, as you will see when solving for Detention Time the resulting answer will not be in hours and will have to be converted. The following formula is used for calculating detention times. $\mathrm{Dt}=\dfrac{\text { Volume }}{\text { Flow }} \nonumber$ The “Pie Wheel” for Detention Time looks like this. “Units” are extremely important with this formula. There are three variables in this formula; Detention Time, Flow, and Volume. Here are some examples for each. Detention Time – seconds, minutes, hours, days Flow – cubic feet per second, gallons per minute, million gallons per day Volume – cubic feet, gallons, million gallons Take note at the above examples. If the units are similar (matching) then dividing volume by flow will yield a time (Detention Time). However, simply dividing a volume by a flow will not result in a time. For example, if you divide gallons by cubic feet per second there is no resulting answer. This is because “gallons” and “cubic feet” will not cancel each other. When solving for Detention Time, the units for Volume and Flow must match. Solving for Detention Time is not the only variable to solve for with this formula. If Detention Time and Volume are given then you will be solving for Flow. Similarly, if Detention Time and Flow are given then you will be solving for Volume. In all of these examples, the units must be similar in order to cancel out and yield your answer. Using the “unit” examples above, list all possible matches of units in order to cancel and yield an answer. Volume Flow Detention Time Remember, using the above examples will not provide any answer in HOURS. Always remember to convert your answer to the units specified in the question. Exercise 9.1 1. What is the detention time in minutes of a 400,000 gallon sedimentation basin with an average flow rate of 5,000 gpm?An 80 foot tall standpipe is ¾ full. What is the pressure in psi at the bottom? 2. What is the detention time in hours through a 100,000 gallon reservoir with a flow rate of 750 gpm?A 12” pipeline is flowing water at a velocity of 3.5 fps. What is the corresponding flow rate? 3. It has been determined that a basin has a detention time of 2 hours and 10 minutes. If the flow through the basin is 2.67 cfs, what is the volume of the basin in gallons?An 18” pipe is flowing 1,500 gpm. What is the velocity? 4. What is the flow rate (in gpm) through a 40 foot wide, 10 foot deep, 50 foot long basin if the detention time is 1 hour and 55 minutes?ng 4.5 MGD at a velocity of 2.45 fps? 5. A 25 foot tall reservoir with a 120 foot diameter has a detention time of 3 hours and 22 minutes. What is the daily flow (in MGD) through the reservoir?A 28 foot tall water tank is sitting on a 75 foot tall hill. What is the pressure in a home at the bottom of the hill? (Assume the pressure gauge is 3 feet from the bottom of the home and the tank is full) 6. A 75 foot long, 30 foot wide, and 20 foot deep basin has a flow of 2.25 MGD. What is the detention time? (Express as hours, minutes, seconds – ex. 5 hours, 3 minutes, and 2 seconds)A home that is receiving water from a water tank that is on top of a 115 foot hill has a pressure of 57 psi. What is the water level in the tank? 7. A series of tracer studies determined that the detention time through a 2,350,000 gallon basin is 2 hours and 12 minutes. What is the daily flow (in MGD)? 8. If a flow of 4.45 cfs is moving through 2 miles of 36” diameter pipe, what is the detention time? 9. A treatment plant has a daily flow of 30 MG. There are two 200,000 gallon sedimentation basins. What is the detention time through the plant. 10. What is the volume of a reservoir that has a detention time of 29 minutes and a flow of 5.4 cfs? 9.02: Weir Overflow Rate Another calculation is one that measures the flow of water over a structure called a “weir.” A weir is an obstruction used to raise the level of flow and evenly disperse it. It allows the measurement of flow to be easily calculated. In a treatment plant process weirs are commonly used to “skim off” the flow of water from the sedimentation process before the water travels to the filters. Weir overflow rates are typically expressed as gallons per minute per foot of weir. They can also be expressed as million gallons per day per foot of weir. The important thing with this formula is that you determine the actual length of the weir and express it using the flow rate specified in the problem. This formula is used: $\text { Weir Overflow Rate (gpm/ft) }=\dfrac{\text { Flow (gpm) }}{\text { Weir Length (ft) }} \nonumber$ Exercise 9.2 1. What is the weir overflow rate of a 100 foot long weir with a flow of 3,450 gpm? 2. A weir over flow rate is 28 gpm/ft with a flow rate of 2,300 gpm. What is the length of the weir? 3. A 75 ft weir has a daily flow 1.25 MG. What is the weir overflow rate? 4. A circular weir with a diameter of 85 feet has a weir overflow rate of 17.5 gpm/ft. What is the flow rate in MGD? (Note: you will need the formula for circumference in this problem) 5. A 8.5 MGD treatment plant has a calculated weir overflow rate of 32 gpm/ft. How long is the weir?

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/09%3A_Water_Treatment_Mathematics/9.01%3A_Detention_Time.txt

Filtration is the last stage in the treatment process for removing particles from the water. The filtration media can vary from sand to gravel to anthracite coal to garnet or a variety of materials layered to trap the remaining suspended solids in the water. Filtration rate is the measure of how much water passes through a certain sized filter over a specific time. Typically filtration rates are expressed in gallons per minute per square foot of filter area (gpm/ft$^2$). It is the flow of water through the surface area of a filter. In the picture below a filter is 5 ft by 5 ft and divided into 1 ft by 1 ft sections. This is done to demonstrate how filtration rates are expressed (in 1 ft$^2$ sections). As flow enters a filter it travels down through the media and then out to either a finished water clear well for distribution or perhaps disinfected prior to delivery. This is the formula used for Filtration Rates: $\mathrm{FR}=\dfrac{\text { Flow }}{\text { SurfaceArea }} \nonumber$ Since Filtration Rates are expressed as gpm/ft$^2$ then it only makes sense to convert the flow rate to gpm prior to dividing by the filter surface area. However, in this equation it is not necessary to do so prior to dividing. The “Pie-Wheel” for Filtration Rates looks like this: Remember that the units for the flow and area will determine the unit for filtration rate. Example $1$ A water treatment plant with a 100 ft2 filter has a flow of 1,650 gpm. What is the filtration rate expressed in gpm/ft$^2$. Solution $\dfrac{1,650 \mathrm{gpm}}{100 \mathrm{ft}^{2}}=16.5 \mathrm{gpm} / \mathrm{ft}^{2} \nonumber$ This is a straight forward example with the units given in the same units requested to be expressed in the answer. Let’s try another. Example $2$ A water treatment plant has an average daily flow of 10.5 MGD. The filter at the end of the treatment process is 22 ft by 15 ft. What is the filtration rate expressed as gpm/ft$^2$? Solution In this question you need to calculate the area of the filter and determine if you want to convert the daily flow to gpm before or after you divide it by the area. Both ways of solving are explained below. $\dfrac{10.5 \mathrm{MGD}}{22 \mathrm{ft} \times 15 \mathrm{ft}}=\dfrac{10.5 \mathrm{MGD}}{330 \mathrm{ft}^{2}}=0.032 \mathrm{MGD} / \mathrm{ft}^{2} \nonumber$ Note that the units are million gallons per day per square feet and need to be converted to gpm/ft$^2$. $\dfrac{0.032 \mathrm{MG}}{\text { Day }}=\dfrac{32,000 \mathrm{gal}}{\text { Day }} \times \dfrac{1 \text { day }}{24 \text { hours }} \times \dfrac{1 \text { hour }}{60 \mathrm{min}}=22.2 \mathrm{gpm} / \mathrm{ft}^{2} \nonumber$ Another way to solve this is to convert the flow to gpm before you divide it by the area. $\dfrac{10,500,000 \text { gal }}{\text { day }} \times \frac{1 \text { day }}{24 \text { hours }} \times \frac{1 \text { hour }}{60 \text { min }}=\frac{7,291.7 \text { gallons }}{\text { minute }} \nonumber$ Then plug this into the filtration rate formula. $\dfrac{7,292 \text { gal }}{22 \mathrm{ft} \times 15 \mathrm{ft}}=\dfrac{7,291 \mathrm{gal}}{330 \mathrm{ft}^{2}}=22.1 \mathrm{gpm} / \mathrm{ft}^{2} \nonumber$ Take note that the answers are slightly different (0.1 off.) This is only due to rounding. If both solutions for this problem are rounded to the same number of digits you would get the exact same answer. Exercise 9.3 (Express all filtration rates as gpm/ft$^2$) 1. A water treatment plant has a typical flow through a 175 ft$^2$ filter of 755 gpm. What is the filtration rate? 2. A circular filter with a diameter of 74 feet receives a flow of 2,200 gpm. What is the filtration rate? 3. A three-hour test revealed that 75,000 gallons passed through a filter with dimensions of 10 ft by 20 ft. Find the filtration rate. 4. A water treatment plant has a total of 4 filters. The plant is designed to treat a daily flow of 7.25 million gallons. The target filtration rate is 2.25 gpm/ft$^2$. Assuming that all 4 filters are identical in size, what is the area of each filter? 5. What is the rated capacity in MGD of a rapid sand filter that is 25 ft long and 16 feet wide when operated at a filtration rate of 1.75 gpm/ft$^2$? 6. It was determined that the optimum filtration rate of a filter with the dimensions of 12 ft wide and 18 feet long is 2.45 gpm/ft$^2$. What is the maximum flow rate in cfs? 7. A water treatment plant treated 70 million gallons through 3 identical filters in one week. If the average filtration rate was 3.15 gpm/ft$^2$, what is the area of each filter? Periodically, filters will need to be cleaned. Cleaning is done through a routine process called backwash. As filters remove particles, the efficiency decreases and the flow rates slow. At predetermined intervals, treatment operators will backwash the filters. Backwashing is nothing more than reversing the flows. However, backwashing rates are typically 10 or more times greater than filtration rates. 1. After 6 hours in operation a 20ft by 30 ft filter required backwashing. Assuming a flow rate of 10,000 gpm, what was the backwash rate? 2. A 15 ft by 17 ft filter was backwashed at a rate of 22.5 gpm/ft$^2$ for 20 minutes. How many gallons were used for the backwashing process? 3. It was determined that a filter with a surface area of 725 ft$^2$ needs to be backwashed for 12 minutes using 94,500 gallons. What would the corresponding backwash rate be in gpm/ft$^2$?

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/09%3A_Water_Treatment_Mathematics/9.03%3A_Filtration_Rate.txt

There are a number of different treatment and distribution water utility careers ranging from laborer to skilled technicians. Each has a very important function in making sure the water system is properly maintained and operates efficiently. Something that is often overlooked in many operator certification courses is a discussion on how a system is planned, designed, constructed, and repaired. While this section of the text will focus on several key aspects of introductory concepts of engineering and construction waterworks mathematics, the following paragraphs will highlight a general overview of the planning, design, construction, and repair processes. 10: Engineering and Construction Planning is important in many aspects of ones life. From planning out your day to planning out a career path, planning is an important step before tackling many different projects. Just as there are various simplicities and complexities to planning in your personal life, the same can be said in the business world. An example of this is building a water treatment plant. This is one of the more complex examples requiring many different phases of planning. A simpler project, which still requires planning, is the construction of a pipeline installation. Let’s take a closer look at several planning steps to a small pipeline installation project. Pipeline Installation Project Planning Budget Any project requires a budget process. There are many different expenses for water utility jobs such as labor, equipment, material, traffic control, disposal, and a variety of other types of costs. Before proceeding with any project, a budget needs to be prepared and staff needs to determine if there is enough money for the project. Environmental Any time a construction project is planned there are various environmental review procedures that must be followed. Will there be any environmental impacts such as air, water, noise, or biological species. Some projects are considered small enough to be exempt, while other larger projects may require extensive environmental impact reports. Timing When will the project be started and completed? Are there enough staff resources available? Water utility operators are very busy and each project needs to have a protect timeline identifying the required resources and expected start and end dates to avoid conflicts. Design In order to properly construct a project there needs to be a minimum amount of engineering work. Some projects, such as water system repairs can require little to no engineering work. While other projects might require extensive engineering design and oversight. Most pipeline construction projects require at least some type of engineering work. The above examples are by no means an exhausted list. However, it does give a good example of the complexities of water utility construction projects. Stationing Stationing is a process to measure distances on construction plans. A “station” is the horizontal measurement distance along a surveyed centerline of a project. Station numbers typically increase from the beginning of a project to the end point of a project. They usually reference points from south to north or from west to east. Station intervals are expressed in 100-foot sections. A half station is 50 feet and is expressed as +50. In order to understand sectioning, take a look at a few examples below: Example \(1\) If a station begins at “0” it is expressed as 0+00. One hundred feet from this station would be expressed as 1+00. One foot sections increase as 0+01. Therefore, after ten feet, it would look like this 0+10. The difference between station 101+00 and 100+00 is 100 feet. If the beginning of a set of construction water plans start at station 100+00 and a valve is located at station 100+99 means the valve is located 99 feet from the start of the plans. The following is an example of someone calculating the distance between two fire hydrants on a set of construction water plans. Example \(2\) Fire hydrant A is located at station 530+50 Fire hydrant B is located at station 527+00 What is the distance between fire hydrant A and B? Solution 53,050 – 52,700 = 350 feet As previously stated, stations typically reference points from south to north and from west to east. However, streets sometimes curve and change directions. An “above” segment on a road simply means a direction toward a higher station. A segment below or behind means a direction toward a lower station number. Exercise 10.1 1. A set of construction water plans shows stationing to mark locations. The start of the plans has a station number of 01+50. The first fire hydrant on the plans is located at station 01+25. How many feet is the fire hydrant located from the start of the plans? 2. A water utility requires fire hydrants to be located 350 feet apart in residential areas. If a street is 1,500 feet long, begins at station 101+55 and the first fire hydrant is located at the start, how many fire hydrants will be installed? 3. A water valve is located at station 345+03 and another at 350+08. What is the distance between the two valves? 4. A domestic water service is located at station 102+45. Two more services need to be installed, one 75 below and one 75 above this station. What is the station of these two new services? Fire hydrant located at 534+00 Valve located at 534+45 Water service located at 532+99 What is the total distance between these items?

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/10%3A_Engineering_and_Construction/10.1%3A_Planning.txt

This text provides a basic look in to water related math problems. Various concepts are introduced and several formulas to apply to those concepts are presented. However, sometimes there are water related math questions, which are basic in nature, but are not part of the framework of the core concepts in this text. This section will attempt to introduce some of those questions and delve into simple math problems presented in questions you may not have seen before. 11: Using What You Learned and Preparing for Certification Exams Let’s start with a simple question: Example $1$ The diameter of a circle is? Solution Upon first examination, the answer appears to be rather obvious. It is “b”, twice the radius. However, whenever a multiple choice question uses an answer such as “e”, both a and b, you need to take a deeper look. In order to rule out answers, you need to have a good understanding of the question. Both of these answers require you to know the formula for circumference to make an educated guess as to whether or not either of these are correct. $\text { Circumference }=\pi \times \mathrm{D} \nonumber$ Knowing this equation allows you to easily rule out both of these possible answers. This was a fairly easy example. Now let’s take a look at something a little more deceiving and requires additional work to solve. Example $2$ One acre-foot of water contains? Solution Upon first glance, most of you might say “b” is the correct answer. You would be correct, because one acre-foot does contain 325,829 gallons. However, there is a better answer. If your next instinct tells you “d” is correct, then you would also be right. Remember, one acre of land is equal to 43,560 square feet. If you fill this land one foot deep, then it becomes 43,560 cubic feet. Therefore, both “a” and “b” are correct answers. However, 1,233,263 liters is a large number and it might actually be equivalent to one acre-foot. Here is where you need to know how many liters are in a gallon. 1 gallon = 3.785 liters Therefore, $325,829 \text { gal } \times 3.785 \mathrm{L}=1,233,262.7 \mathrm{L}$ So, the best answer is “e” all of the above. Meter reading is a common task for both water distribution and treatment operators. Mechanical equipment such as, meters, pumps and motors require maintenance and have a certain operating life. In addition, knowing how much water a utility pumps and sells is critical to a utilities revenue stream. There are flow meters and hour meters at various facilities in a water system. Understanding some of the terminology is critical to understanding how to solve some very basic math problems. Example $3$ A water treatment operator had a start read of a certain pump on January 1 and an end read on January 31. If the start read was 1,200,425 gallons and the end read was 6,342,076 gallons how much water flowed through this pump? Solution This is a relatively simple subtraction problem but you need to know what “start” and “end” reads are. Flow meters can be read daily, weekly, monthly, etc. A “start” read is nothing more than the beginning read of a certain period. In this example a monthly read. The “end” is then the last read of a certain period. So in this example, letter “c” is the correct answer, 5,141,651 gallons flowed through this pump in the month of January. Do you notice anything else interesting with this question? All the answers have similar numbers, just an order of magnitude different. The certification exams often do this to try and confuse test takers. Sometimes people get confused and might see a comma as a decimal and will select the incorrect answer. These are only a few examples of some very basic problems and some test taking tips when you finally begin taking operator certification exams. Below are a series of questions to further illustrate the subtle differences in ways of asking questions. Exercise 11.1 1. You are to excavate a pipe trench that is 300-feet in length, 6-feet deep, and 3-feet wide, and export all of the soil removed. Your dump truck holds 10 yards. How many trips will your truck need to make to complete the job? 1. 5 2. 10 3. 15 4. 20 5. 25

textbooks/workforce/Water_Systems_Technology/Water_130%3A_Waterworks_Mathematics_(Alvord_and_Blasberg)/11%3A_Using_What_You_Learned_and_Preparing_for_Certification_Exams/11.1%3A_Examples.txt

“Will I ever use UDA in real life?” This sort of question usually pops into the heads of students in all subjects, but in math, it happens quite often. In a practical sense, UDA can be looked at as converting between currencies. If you travel to Europe for example, you will want to know how many Euros equal a dollar. Or you may want to figure out how fast you are driving, in which case you would need to convert kilometers per hour into miles per hour. However, in the “world” of water, converting of units is commonplace. The following few questions are written with the perspective of “real world” scenarios. Exercises A water utility manager has been asked to prepare an end of year report for the utility’s Board of Directors. The utility has 4 groundwater wells and two connections to a surface water treatment plant. Complete the table below. Source of Supply Flow Rate (gpm) Daily Operation (Hrs) Total Flow (MGD) Annual Flow (AFY) Well 1 800 10 Well 2 1,000 8 Well 3 650 16 Well 4 2,250 11 SW Pump 1 1,750 7 SW Pump 2 1,500 9 Using the information from the above problem, fill in the table below. Source of Supply Annual Production (AFY) Cost per AF (\$/AF) Total Annual Cost (\$) Well 1 60 Well 2 60 Well 3 95 Well 4 95 SW Pump 1 450 SW Pump 2 450 Total Annual Cost Connection Type Number of Connections Average usage per day per connection (gallons) Average Monthly Usage per Connection Type (CCF) Residential 835 Commercial 1,370 Industrial 2,200 2.01: The Shapes of Things In order to transport water from the source to treatment, to the distribution system, and, eventually, to the customer, it needs to flow through geometric shapes. An aqueduct brings water from Northern California to Southern California. Reservoirs and tanks store water before it enters the treatment process. Pipes flow water throughout the treatment plant and through the distribution system. Above ground storage tanks and elevated storage tanks hold water and provide pressure to the distribution system. This is a crude description of the path water takes, but it illustrates the point of different structures and shapes that water must transfer through. Areas Calculating areas is the first step in working with geometric shapes. Areas are used to determine how much paint to buy, how much water can flow through a pipe, and many other things. A circle, a rectangle, and a trapezoid are probably the most common shapes you will encounter in the water industry. However, a sphere, a triangle, a half circle with a rectangle can also be found. These are the structures we will focus on in this chapter. $0.785 \mathrm{D}^{2} \quad \mathrm{LW}\left(\frac{b_{1}+b_{2}}{2}\right) H$ $\frac{\left(0.785 \mathrm{D}^{2}\right)}{2}+\mathrm{LW} \quad 4\left(0.785 \mathrm{D}^{2}\right) \quad \pi \mathrm{DH}$ Circles To calculate the area of a circle, multiply 0.785 by the diameter squared. This means to multiply the diameter times 0.785. If you recall from the 030 course, we use 0.785 in the “area” formula. $A = 3.14 \times r^2$ or $A = 0.785 \times d^2$ 0.785 replaces $\pi$ and diameter replaces radius. Diameter squared is four times greater than radius squared and 0.785 is one-fourth of $\pi$. Take special note of the units for the diameter. Many times (especially when talking about pipes) the diameter will be given on some other unit besides feet (e.g. inches). Converting the diameter to feet as your first step will avoid ending up with squared units other than square feet. Sometimes the diameter of a pipe might be given in metric units. This is common when working with the California Department of Transportation. Examples What is the area for each of the following diameters listed below? Given Diameter Conversion Formula Answer 24 in 24 in / 12 in = 2 ft 0.785 x (2 ft)2 3.14 ft2 130 in 130 in / 12 in = 10.8 ft 0.785 x (10.8 ft)2 91.5 ft2 813 mm 813 mm / 304.5 mm = 2.67 ft 0.785 x (2.67 ft)2 5.6 ft2 Rectangles Calculating the area of a rectangle or a square simply involves multiplying the length by the width. If you are painting the walls, ceiling, or floors of a room the perspective changes slightly. For example, the dimensions of a wall might look like a width and height when you are standing looking at it. A floor might look like a width and a length. Regardless of the perspective, the area formula is the same. Examples What is the area for each of the following rectangles listed below? • Length = 30 ft, width = 10 ft 30 ft x 10 ft = 300 ft2 • Height = 15 ft, width = 7 ft 15 ft x 7 ft = 105 ft2 Trapezoids Trapezoids are most commonly the shape of an aqueduct. Aqueducts are typically miles and miles of trapezoidal shaped concrete channels. They have flat narrow bottoms that slope up to wider distances at the top. In order to calculate the varying distances across a trapezoid, add the distance (width, b2) across the bottom to the distance (width, b1) across the top and divide by 2. This gives the average width. Then multiply the average width by the height or depth of the trapezoid to calculate the area. Examples • Widths = 5 ft and 7 ft, height = 6 ft • (5 ft + 7 ft) / 2 x 6 ft = 36 ft2 • Widths = 8 ft and 12 ft, depth = 10 ft • (8 ft + 12 ft) / 2 x 10 ft = 100 ft2 Spheres and Other Shapes As previously stated, circles, rectangles, and trapezoids are the most common shapes in the water industry. However, large standpipes shaped like a cylinder with a sphere on top or an elevated storage tank shaped like a sphere can be very common in the mid-west. Half circles and rectangles can also be found as reservoirs or sedimentation basins. Therefore, understanding how to calculate the area for these types of structures is also important. The distance around the cylinder is calculated as Pi (3.14) multiplied by the diameter. Pi is a unitless constant. It can also be looked at as the “length” around a cylinder. Once the “length” is calculated multiply this number by the height or depth to get the area. Examples • D = 100 ft, height = 20 ft • 3.14 x 100 ft = 314 ft (which is “L”) • 314 ft x 20 ft = 6,280 ft2 When the area is calculated for a sphere, it is the entire surface area of a “ball.” Spheres can be commonplace in the mid-west as elevated storage structures. The formula for the area of a sphere is 4 times 0.785 times the diameter squared. Examples D = 50 ft 4 x 0.785 x (50 ft)2 = 7,850 ft2 D = 35 ft 4 x 0.785 x (35 ft)2 = 3,845 ft2 Volumes In order to calculate the volume inside a structure, a third dimension needs to be included in the “area” formula. For example, if a circle is given a length or height, it becomes a cylinder and a volume can be calculated. If a trapezoid or a rectangle has a length it becomes a three-dimensional structure with a volume that can be calculated.

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/01%3A_Unit_Dimensional_Analysis_(UDA)/1.01%3A_Applying_the_Math_of_UDA.txt

As with all mathematical computations, there is an element of “Will I ever use this outside of the classroom?”. The answer is most likely “sometimes.” An operator might calculate the volume of water in a storage structure or pipeline to determine how much chlorine is needed to disinfect the structure. A contractor might calculate the internal surface area of a tank to determine the amount of coating that is required. Or, you might be asked to paint the interior walls of a room. Putting practical use to mathematical equations can help in the student’s overall understanding. The following problems are some “real-world examples” you might find working as a water utility operator. 3.01: It's All About the Weight Water is essential for the survival of all life forms. It makes up approximately 60% of our total body weight and as much as 75% of the earth’s surface. So, how much does water actually weigh? There are a few variables, such as temperature, that determine the weight of water, but for all practical purposes in waterworks mathematics, water weighs 8.34 pounds per gallon. The density (mass per unit volume) of water is 1.00. This is also referred to as specific gravity. When discussing specific gravity, many things are compared to water. For example, if something has a specific gravity less than water (<1), then the substance will float on water. Conversely, if a substance has a specific gravity greater than 1, it will sink in water. The table below lists common specific gravities/densities and weight of substances used in the waterworks industry. Remember, these are only examples and should not be put to memory. On any State exam, you will be given the specific gravity or corresponding weight of the substance in the question. Substance Specific Gravity Weight Crude Oil 0.815 6.80 lbs/gal Water 1.00 8.34 lbs/gal Chlorine (g) 2.49 20.77 lbs/gal Calcium hypochlorite 2.35 19.60 lbs/gal Alum 1.16 – 1.40 9.67 – 11.68 lbs/gal Ferric chloride 1.43 11.93 lbs/gal Examples Since water is the reference, then a specific gravity (SG) of 1 and a weight of 8.34 lbs/gal are the numbers needed to calculate the SG and weight of other substances. What is the weight of a substance in lbs/gal if it has a SG of 1.25? Remember, anything that has a SG >1 will weigh more than 8.34 lbs/gal. • 8.34 lbs/gal1 SG x 1.25 SG1 = 10.43 lbs/gal What is the SG of a substance that weighs 5.75 lbs/gal? Remember, anything with a weight <8.34 lbs/gal will have a SG <1. • 1 SG8.34 lbs/gal x 5.75 lbs/gal1 = 0.69 SG Exercises Solve the following density related problems. 3.02: Parts Per Hundred vs. Parts Per Million It is important to understand the relationship between percentage and parts per million (ppm). Most of the time, chemical concentrations are expressed in percentages (parts per hundred, pph.) However, in chemical dosage related problems, concentrations are expressed in ppm. Therefore, it shouldn’t be too difficult to convert percentage to ppm and ppm to percentage. It is simply a difference of 10,000. If you divide 1,000,000 or 1 ppm by 100 or 100% you get the following. 1,000,000 ÷ 100 = 10,000 This translates a 1% solution concentration to 10,000 ppm. 1% = 10,000 ppm In other words, just multiply the percent solution by 10,000 to calculate ppm. See the table below for other examples of percent concentration to ppm equivalents. Percent Concentration ppm 1% 10,000 ppm 2% 20,000 ppm 3% 30,000 ppm 10% 100,000 ppm Another concept that needs to be addressed is the difference between ppm, parts per billion (ppb), and parts per trillion (ppt.) As water quality regulations become more stringent and laboratory analysis techniques get better and better, contaminants are being identified at lower and lower levels. Most water quality standards are expressed in ppm or milligrams per liter (mg/L), but many are expressed in ppb or micrograms per liter (ug/L), and a few are expressed in ppt or nanograms per liter (ng/L). A simple exercise can help with understanding the different ways to express the amount of contaminant in water supplies. 1,000,000 – million 1,000,000,000 – billion 1,000,000,000,000 – trillion 1 ppm = 1,000 ppb = 1,000,000 ppt The expression above says that 1 part of a small number (ppm) equals 1,000 parts of a smaller number (ppb) which equals 1,000,000 parts of an even smaller number (ppt.) Exercises Solve the following problems. Think of the “%” symbol as “pph” (parts per hundred) Constituent ppm ppb ppt Arsenic 10 Chromium 0.05 Nitrate (NO3) 45 Perchlorate 6,000 Vinyl chloride 0.5

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/02%3A_Geometric_Shapes/2.02%3A_Applying_the_Math_of_Geometric_Shapes.txt

It's pretty easy to calculate how many pounds of chlorine are needed to provide a certain dosage if we are using 100% gas chlorine. Most operators in the water industry have put to memory the “Pound Formula” by multiplying the flow or volume of water in MG or MGD by 8.34 pounds per gallon and then by the dosage in ppm, the pounds of chlorine needed is calculated. $MG \times 8.34\, lbs/gallon \times ppm = lbs \label{eq1}$ or $\dfrac{MG}{Day} \times 8.34\, lbs/gallon \times ppm = lbs/day \label{eq2}$ However, in many treatment plants and at treatment sites within distribution systems, the use of gas chlorine is in decline, unless the plant is of considerable size. The reduction in chlorine gas usage is primarily due to safety concerns and other forms of chlorine being more cost-competitive. For example, groundwater wells are commonly disinfected with solid (calcium hypochlorite) or liquid (sodium hypochlorite) forms of chlorine. In addition, other chemicals such as Alum, ferric chloride, sodium hydroxide are used in varying concentration strengths at treatment plants in addition to chlorine. Most often these chemicals are not in the pure 100% form. When solving dosage problems with chemicals of different strength the following two statements are helpful in remembering whether you need to multiply or divide by the percent concentration. “If you are solving for pounds you divide by the percent concentration.” “If pounds are given you multiply by the percent concentration.” Therefore, if you are calculating for the amount of pounds needed you divide by the decimal equivalent of the percent concentration. You need more of the chemical since it is not 100% and dividing by a number less than one yields a larger number. If the amount of pounds is known, then by multiplying by the decimal equivalent of the percent concentration you will calculate how much of that chemical is available in the total pounds of the substance. Multiplying by a number less than one yields a smaller number. Once you understand the concept behind the problem it makes solving them easier. Think of it this way... it takes much more 10% ferric chloride in the coagulation process than let's say ferric chloride at 75% strength. The same is true if you are using calcium hypochlorite as opposed to gas chlorine, because gas is a greater strength than calcium hypochlorite. Similarly, if you have 100 pounds of 65% calcium hypochlorite, you don’t have 100 pounds of chlorine. Only 65% or 65 pounds of the substance is actually chlorine. As opposed to 100 pounds of gas chlorine which is 100 pounds of available chlorine. When using chemicals of different strengths, the pound formula can be looked at like this: % concentration ___________ MG x 8.34 lbs/gallon x ppm = lbs % concentration ___________ MG/Day x 8.34 lbs/gallon x ppm = lbs/day Placing the decimal equivalent of the percent concentration of the chemical being used under the left side of the equation will allow the appropriate amount of chemical needed to be calculated. In addition, if MG or ppm are the unknowns, the percent would be multiplied by the weight of the chemical in pounds. Examples are provided later in this section. The last chemical dosage concept we need to look at is when the chemical being used is in the form of a liquid. Since the Pound Formula is after all measuring chemicals in “pounds,” then the chemical needs to be expressed as pounds. In Section number 3, we learned about specific gravity and how it affects the weight of a substance. You will need to use that information when presented with a pound formula question where the chemical used is a liquid. Finally, a general understanding of chlorine dosage is needed. The concept is straightforward. The reason drinking water is disinfected is to prevent pathogenic organisms from contaminating the supply causing illness to the population drinking the water. The amount of disinfectant added is not always what is measured later by a water utility operator. Typically the amount of disinfectant measured after the original dosage occurs is lower than the dosage measured which is referred to as the residual. What happens to the disinfectant? The chlorine that “disappears” is the chlorine demand. It is the amount of chlorine that is inactivating the pathogens. Once the demand is satisfied, the remaining chlorine is termed the residual. This formula is provided below. $\text{Dosage} = \text{residual} + \text{demand}$ Example $1$ How many pounds of chlorine are needed to dose 2 MG of water to a dosage of 3.25 ppm? Solution We use Equation \ref{eq1} to solve this. \begin{align*} MG \times 8.34\, lbs/gallon \times ppm &= lbs \[4pt] 2\, MG \times 8.34\, lbs/gal \times 3.25 ppm &= 54.21\, lbs \end{align*} In the example above, it is a straightforward chemical dosage problem. Example $2$ How many pounds of 10% Alum are needed to dose a treatment flow of 5 MGD to a dosage of 10 ppm? Solution We use Equation \ref{eq2} to solve this (5 MG/Day x 8.34 lbs/gallon x 10 ppm)/0.1 = lbs/day 417/0.1 = 4,170 lbs/day It takes 417 lbs of Alum to dose 5 MGD to 10 ppm. However, in this problem, the Alum being used is only a 10% concentration. Therefore, you need to divide by 10% (or 0.1) to calculate the total amount of this form of Alum that is needed. Example $3$ How many gallons of 15% strength sodium hypochlorite are needed to dose a well flowing 1,500 gpm to a dosage of 1.75 ppm? (Assume the sodium hypochlorite has a specific gravity of 1.42) Solution First, the flow rate needs to be converted to MGD. 1,500 gpm x 1440 = 2,160,000 GPD or 2.16 MGD (2.16 MG/Day x 8.34 lbs/gallon x 1.75 ppm)/0.15 = 210 lbs/day 210 lbs of 15% sodium hypochlorite are needed to dose 1,500 gpm to 1.75 ppm. Now the 210 lbs need to be converted to gallons. 210 lbs/day x gallons/(8.34 lbs x 1.42) = 17.75 gal/day Exercises Solve the following chemical dosage problems. Be sure to account for the differences in chemical percent concentrations. 1. Sodium hypochlorite = $2.45 per gallon 2. HTH =$1.65 per pound

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/04%3A_Chemical_Dosage_Analysis/4.01%3A_It%27s_a_Pound_Formula.txt

• 5.1: What's a Weir? A weir is an overflow structure that is used to alter flow characteristics. A weir meters flow to a specific rate known as the Weir Overflow Rate (WOR.) WORs are expressed as the flow of water by the length of the weir, typically as MGD per foot (MGD/ft) or gpm per foot (gpm/ft). 05: Weir Overflow Rate A weir is an overflow structure that is used to alter flow characteristics. In the example below, the water is flowing from left to right. The black triangular-shaped structure is the weir. It is impeding the flow of water causing the water to flow over the weir structure. It raises the level of flow to evenly disperse the water. A weir meters flow to a specific rate known as the Weir Overflow Rate (WOR.) WORs are expressed as the flow of water by the length of the weir, typically as MGD per foot (MGD/ft) or gpm per foot (gpm/ft). Weir Overflow Rate Formula Weir Overflow Rate (gpm/ft) = Flow (gpm)/Length of Weir (ft) Calculating the length of the weir is required in order to calculate the WOR. Sometimes the weir can be a circular structure requiring the circumference to be calculated in order to find the actual length. Other times it is a linear structure, in which case the length would be known. Weirs can either be sharp-crested or broad-crested. Broad-crested weirs are flat-crested structures and are commonly used in dam spillways. Sharp-crested weirs (most common are “V” notch) allow the water to fall cleanly away from the weir and are typically found in water treatment plants. Exercises 1. What is the weir overflow rate through a 7 MGD treatment plant if the weir is 30 feet long? (Express your answer in MGD/ft and gpm/ft). 2. A drainage channel has a 10-foot weir and a weir overflow rate of 7 gpm/ft. What is the daily flow expressed in MGD? 3. What is the length of a weir if the daily flow is 8.45 MG and the weir overflow rate is 28 gpm/ft? 4. A 60 ft diameter circular clarifier has a weir overflow rate of 15 gpm/ft. What is the daily flow in MGD? 5. A treatment plant processes 15 MGD. The weir overflow rate through a circular clarifier is 29.5 gpm/ft. What is the diameter of the clarifier? 6. An aqueduct that flowed 36,000 acre-feet of water last year has a weir overflow structure to control the flow. If the weir is 250 feet long, what was the average weir overflow rate in gpm/ft? 7. A 75-mile aqueduct is being reconstructed to widen the width across the top. The width across the bottom is 10 feet and the average water depth is 15 feet. The aqueduct must maintain a constant weir overflow rate of 25 gpm per foot with a daily flow of 0.63 MGD. What is the length of the weir? 8. An engineering report determined that a minimum weir overflow rate of 15 gpm per foot and a maximum weir overflow rate of 20 gpm per foot were needed to meet the water quality objectives of a certain treatment plant. The existing weir is 80 feet long. What is the daily treatment flow range of the plant? 9. A circular clarifier processes 12.5 MGD with a detention time of 2.35 hours. If the clarifier is 50 feet deep, what is the diameter? 10. A water treatment plant is in the process of redesigning its sedimentation basin. The plant treats 4.5 MGD with an average detention time of 1.85 hours. Portable storage tanks will be used when the basin is under construction. The portable storage tanks are 25 ft tall and 20 ft in diameter. How many tanks will be needed?

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/05%3A_Weir_Overflow_Rate/5.01%3A_What%27s_a_Weir.txt

Detention Time is an important process that allows large particles to “settle out” from the flow of water through gravity, prior to filtration. It is the time it takes a particle to travel from one end of a sedimentation basin to the other end. Conventional filtration plants require large areas of land in order to construct sedimentation basins and employ the detention time process. Not all treatment plants have the available land and may decide that direct filtration is suitable. Therefore, in direct filtration plants, the sedimentation process is eliminated. However, in direct filtration plants, the filters have shorter run times and require more frequent backwashing cycles to clean the filters. A term used that is interchangeable with detention time is contact time. Contact times represent how long a chemical (typically chlorine) is in contact with the water supply prior to delivery to customers. For example, contact time can be measured from the time a well is chlorinated until it reaches the first customer within a community. Or, it could be how long the water mixes in a storage tank before it reaches a customer. Calculating the Detention Time and Contact Time requires two elements, the volume of the structure holding the water (sedimentation basin, pipeline, and storage tank) and the flow rate of the water (gallons per minute, million gallons per day, etc). Since detention times and contact times are typically expressed in hours, it is important that the correct units are used. When solving Dt problems be sure to convert to the requested unit of time. As with all water math-related problems, there are other parameters that can be calculated within the problem. For example, if the detention time and volume are known, then the flow rate can be calculated. Or, if the flow rate and detention time are known, the volume can be calculated. Sometimes the flow rate and the desired detention time is known and the size of the vessel holding the water needs to be designed. In this example, the area or dimensions of the structure can be calculated. The chart above shows a simple way of calculating the variables. If the variables are next to each other (Dt and Flow Rate) then multiply. If they are over each other (Volume and Dt or Volume and Flow Rate) then divide. The Detention Time formula is: $\text{Detention Time (Dt)} = \dfrac{\text{Volume}}{\text{Flow}}$ • When solving this equation make sure the units are correct Take a look at the examples below. • $\text{Dt}$ = Volume/Flow • gallons/(gallons/minute) • cubic feet/(cubic feet/second) • gallons/(million gallons/day) In the first two examples above, the terms can be divided. However, in the third example, they cannot. Dt should be expressed as a unit of time (i.e., sec, min, hours). If you divide the first two examples (gal/gpm and cf/cfs), you will end up with minutes and seconds, respectively. However, in the third example, gallons and million gallons cannot cancel each other out. Therefore, if you had 100,000 gallons as the volume and 1 MGD as the flow rate: 100,000 gallons/1 MGD Then you would need to convert 1 MGD to 1,000,000 gallons per day in order to cancel the unit gallons. The gallons then cancel leaving “day” as the remaining unit. 100,000 gallons/(1,000,000 gallons/1 day) = 0.1 day Converting to hours from days is easy, simply multiply by 24 hours per day. 0.1 day/x = 24 hours/1 day = 2.4 hours Sometimes, this can be the simplest way to solve detention time problems. However, people can be confused when they get an answer such as 0.1 days. There are other ways to solve these problems. One way is to convert MGD to gpm. Using the above example, convert 1 MGD to gpm. 1,000,000 gallons/1 day x 1 day/1,440 minutes = 694.4 gpm Now solve for the Detention Time. 100,000 gallons/(694.4 gallons/min) = 144 minutes x 1 hour/60 minutes = 2.4 hours If the question is asking for hours there still needs to be a conversion. However, 144 minutes is more understandable than 0.1 days. Exercises Solve the following problems. Be sure you provide the answer in the correct units.

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/06%3A_Water_Treatment_Math_Detention_Time/6.01%3A_It%27s_a_Lag_in_Time.txt

One of the most important processes in a water treatment plant is filtration. It is the last barrier between the treatment process and the customer. Filters trap or remove particles from the water further reducing the cloudiness or turbidity. There are different shapes, sizes, and types of filters containing one bed or a combination of beds of sand, anthracite coal, or some other form of granular material. Slow sand filters are the oldest type of municipal water filtration and have filtration rates varying from 0.015 to 0.15 gallons per minute per square foot of filter bed area, depending on the gradation of filter medium and raw water quality. Rapid sand filters, on the other hand, can have filtration rates ranging from 2.0 to 10 gallons per minute per square foot of filter bed area. Typically rapid sand filters will require more frequent backwash cycles to remove the trapped debris from the filters. Backwashing is the reversal of flow through the filters at a higher rate to remove clogged particles from the filters. Backwash run times can be anywhere from 5–20 minutes with rates ranging from 8 to 25 gallons per minute per square foot of filter bed area, depending on the quality of the pre-filtered water. Filtration and backwash rates are calculated by dividing the flow rate through the filter by the surface area of the filter bed. Typically these rates are measured in gallons per minute per square foot of filter bed area. • Flow Rate (gpm)/Surface Area (sq.ft) = Filtration Rate Although filtration rates are commonly expressed as gpm/ft2 they are also expressed as the distance of fall (in inches) within the filter per unit of time (in minutes). During backwashing it is expressed with the same units only per “rise” in the filter. See the example below. • Filtration Rate = Fall (inches)/Time (min) • Backwash Rate = Rise (inches)/Time (min) Examples Express 2.5 gpm/ft2 as in/min. First, convert gpm to cfm. The purpose of this is to begin matching the unit of “inches” in in/min to the “cubic feet in cfm. • (2.5 gal/min)/sq.ft x 1 cf/7.48 gal = 0.33 cfm/sq.ft • 2.5 gpm/sq.ft x 1 cf/7.48 gal = 0.33 cfm/sq.ft If you look at the above answer of (0.33 cf/m)/sq.ft more closely you can see that it can also be expressed as 0.33 ft/min since the sq.ft and cf cancel each other to feet. Once you have “feet per min” you can easily convert to “inches per min” by multiplying by 12. • 0.33 ft/min x 12 in/1 ft = 4 in/min Let’s try another example: What is the filtration rate through a 20’ by 20’ filter if the average flow through the treatment is 2.5 MG? First, convert 2.5 MGD to gpm. To do this divide 2.5 MGD by 1,440. • 2,500,000 gal/day x 1 day/1,440 min = 1,736 gpm Then divide the flow by the area of the filter (20’ x 20’ = 400 sq.ft). • 1,736 gpm/400 sq.ft = 4.34 gpm/sq.ft Now, calculate the inches per minute. Instead of 7.48 gallons per cubic foot and 12 inches per foot, there is a conversion factor that can also be used. • 1.6 in/min = 1 gpm/sq.ft

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/06%3A_Water_Treatment_Math_Detention_Time/6.02%3A_Filtration_Rates.txt

CT stands for Concentration and Time. As soon as a disinfectant is added to water it begins the disinfection process. What is the concentration of the disinfectant and how long is it in contact with the water? It takes “time” to complete the disinfection process. In addition, there are other variables that can delay the disinfection process such as, pH, water temperature, turbidity, and the amount of pathogens in the water among other things. Therefore, knowing the CT (concentration of the disinfectant and the time the disinfectant has to do its “work”) is very important in ensuring that the water is properly disinfected and safe for human consumption. 07: CT Calculations As part of the Safe Drinking Water Act, there are a set of regulations known as the Surface Water Treatment Rule (SWTR.) The first version of the SWTR enacted in 1989 required inactivation percentages for Giardia of 99.9% and for viruses of 99.99%, among other things. In 1998, the Interim Enhanced Surface Water Treatment Rule (IESWTR) was introduced adding the 99% inactivation of Cryptosporidium to the list. In 2002, the Long Term 1 Enhanced Surface Water Treatment Rule was announced with the Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) following soon after in 2003. This text focuses on the basic elements of CT calculations and the inactivation of Giardia and viruses. In order to be in compliance with the SWTR, drinking water treatment plants must meet the following inactivation requirements: • Giardia lamblia – 3.0 Log or 99.9% Inactivation • Viruses – 4.0 Log or 99.99% Inactivation • Cryptosporidium parvum – 2.0 Log or 99% Inactivation The table below compares the Log and Percent Inactivation values. Table 7.1. Log Percent and Inactivation Values Log Inactivation Expressed as Log Log Value Percent Inactivation 0.5 100.5 3.162 68.38 1.0 101.0 10 90.00 2.0 102.0 100 99.00 3.0 103.0 1,000 99.90 4.0 104.0 10,000 99.99 5.0 105.0 100,000 99.999 6.0 106.0 1,000,000 99.9999 7.0 107.0 10,000,000 99.99999 Updated versions of the act were published in 2002 and 2003 as the LT1ESWTR and LT2ESWTR respectively. A simple calculation can be used to determine the percent inactivation or the log inactivation if one or the other is known. The following formula can be used to calculate the percent inactivation if the log inactivation is known. Converting from Log to Percentage Example • 0.5 Log • (1 - (1/10log inactivation)) x 100 • (1 - (1/100.5)) x 100 • (1 - (1/3.16)) x 100 = 68% • 3.0 Log • (1 - (1/10log inactivation)) x 100 • (1 - (1/103)) x 100 • (1 - (1/1000) x 100 = 99.9% The following formula can be used to calculate the log inactivation if the percent inactivation is known. Converting from Percentage to Log Example • 68.38% • 100/(100 - Percent Inactivation) = Log Inactivation • 100(100 - 68.38) = 3.162 • 3.162 = 100.5 = 0.5 Log Use the Log or exponent function on your calculator to solve 100.5 to get 3.162. • 99.9% • 100/(100 - Percent Inactivation) = Log Inactivation • 100(100 - 99.9) = 1,000 • 1,000 = 103 = 3 Log Although the above formulas can be used, we typically only deal with Giardia (3 Log or 99.9%), viruses (4 Log or 99.99%), and Cryptosporidium (varies) so you only need to remember a few values. Cryptosporidium will not be discussed in this class due to the complexities of the LT2ESWTR regulations. Surface water must go through some type of treatment. Disinfection can be used as the sole means of meeting the CT requirements. However, various treatment processes account for some of the inactivation or removal of pathogens. Therefore, the SWTR provides “credits” toward the inactivation of Giardia and viruses. For example, the CT requirement for viruses is 4 Log. If a treatment process received 1 Log credit, then the disinfection requirement for viruses would be 3 Log (4 – 1 = 3.) The table below shows the various credits and resulting disinfection requirements. Table 7.2. Treatment Credits and Log Inactivation Requirements Treatment Log Inactivation Requirements Removal Credit Logs Required Log Inactivation from Disinfection Giardia Viruses Giardia Viruses Giardia Viruses Conventional 3 4 2.5 2 0.5 2 Direct Filtration, DE, or Slow Sand 3 4 2 1 1 3 As previously mentioned CT stands for Concentration and Time. Concentrations are expressed in mg/L and Time in min, therefore CT is expressed as (mg/L · min). When solving CT problems, the concentration of the disinfectant is typically provided in the question. However, there may be times when the chemical dosage formula is needed. In order to calculate the time (contact time to be exact), the detention time or “plug flow” formula will be needed. Time is defined as the time the disinfectant is in contact with the water to the point where the Concentration is measured. These times are easily calculated through pipelines and reservoirs, but sometimes they can be difficult to calculate through various treatment processes. In this case, Tracer Studies are sometimes conducted. T10 represents the time for 10% of an applied tracer mass to be detected through a treatment process or, the time that 90% of the water and pathogens are exposed to the disinfectant within a given treatment process. Some problems will require the calculation of the contact time while others will provide T10 values. Once the actual CT values have been calculated, the final step in the CT calculation process involves CT Tables. The U.S. Environmental Protection Agency (USEPA) as part of the SWTR, created a series of tables that list the type of disinfectant, the pH of the water, the concentration of the disinfectant, the contact time, and the pathogen in question. Using all this information, the required CT (mg/L · min) values can be found. For your reference, the CT Tables are provided at the end of this text. They can be confusing at first, but once you understand what information you need to look for, the CT values can be easily found. In the paragraph above, two terms were used; “actual CT” and “required CT.” Actual CT is the actual concentration through the treatment process and the actual time the disinfectant is in contact with the water. For example, if the contact time is 10 minutes and the concentration is 0.2 mg/L then the actual CT is 0.2 mg/L times 10 minutes which equals 2 mg/L · min. The CT Tables give you the required CT, the required concentration time needed to inactivate either Giardia or viruses. The ratio of the actual CT and the required CT is then calculated. If the actual CT is equal to or greater than the required CT then the ratio is equal to or greater than 1.0 and CT is met. If the actual CT is less than the required CT then the ratio would be less than 1.0 and CT would not be met. The following examples show how to calculate CT problems from start to finish. Example A typical question will provide the pH, the temperature, the pathogen of interest, the type of disinfectant, the dosage or a way to calculate the dosage, and the type of treatment. An example of this data is provided below. • pH – 7.5 • Temperature – 10°C • Disinfectant – Free chlorine • Dosage – 0.2 mg/L • Pathogen – Giardia • Treatment – Direct Filtration Use this information to find the appropriate CT Table to use. You should discover that Table C-3 is the correct table to use for this data set. For a quick reference, this table is presented on the next page. Finding Required CT The title of the table tells you which CT value the table will provide. This table is for Giardia, with free chlorine as the disinfectant, at a temperature of 10°C. Now you need the other information (pH and dosage concentration.) There are seven (7) boxes in the table each with different pH values. Look for the one that says pH = 7.5. On the far left of the table, you can find the varying disinfectant concentrations, starting with less than or equal to 0.4 mg/L going up to 3 mg/L. Since the problem states a dosage of 0.2 mg/L, you’ll need to use the first row of the table. You now need the last bit of information, the treatment process. In this instance, it is Direct Filtration. Remember, Giardia has an inactivation requirement of 3 Log. If there was no treatment process you would be looking at the last column under pH of 7.5. However, referring back to Table 7.1 you can identify the Log credit and resulting disinfection inactivation requirements. You should come up with a required inactivation from disinfection of 1 Log. Using the first row for disinfectant concentration and the second column from the 7.5 pH portion of the table, you should come up with a required CT of 42 mg/L · min. Calculating Actual CT There can be multiple locations where a disinfectant is added to the water during the treatment process. Sometimes the water is pre-chlorinated in the raw water pipeline leaving a storage reservoir prior to entering the treatment facility. Sometimes the water is disinfected before the coagulation flocculation process and many times the water is disinfected after filtration prior to delivery to customers. Every time chlorine is added to the water supply it counts towards the inactivation of pathogens. Each step of the way CT will need to be calculated. The example information below will help illustrate this concept. Free chlorine is added at a concentration of 0.2 mg/L in a 12” diameter 5,000-foot long pipeline leaving a storage reservoir prior to entering the treatment plant. The flow through the pipeline is 2 MGD. Using this information, the time 0.2 mg/L of free chlorine is in contact with the water can be determined using the Detention Time formula. • Dt = Volume/Flow • Volume = 0.785 x D2 x L • Volume = 0.785 x 1’ x 1’ x 5,000’ x 7.48 gal/ft3 = 29,359 gallons • Flow = 2 MGD = 1,389 gpm • Dt = 29,359 gal/1,389 gpm = 21 minutes Multiply the detention time by the concentration and you get CT. • 0.2 mg/L x 21 minutes = 4.2 mg/L · min So, the actual CT through the pipeline is 4.2 mg/L · min. Tracer studies (T10) have determined that a free chlorine concentration of 1.2 mg/L through the treatment plant is 20 minutes. With this information, you can calculate the CT through the plant. $1.2\, mg/L \times 20\, minutes = 24 \,mg/L \cdot min$ Since both sections are disinfected with the same chemical, the two CT values can be added together. $4.2\, mg/L \cdot min + 24\, mg/L \cdot min = 28.2\, mg/L \cdot min$ The following table is used to organize the data. Location and Type of Disinfection Actual CT Required CT CT Ratio Pipeline + Plant (free chlorine) 28.2 mg/L · min 42 mg/L · min 0.67 Since the ratio of actual to required CT is less than 1.0, then CT is not met. If a treatment plant does not meet CT it can either increase the detention time through the pipeline or plant or it can increase the dosage. In a situation where two different disinfection chemicals are used, the required CT values would be different and you would not add the different disinfecting locations together. The next example illustrates this scenario. Example A conventional water treatment plant receives water with a 0.4 mg/L free chlorine residual from 9,000 feet of 3-foot diameter pipe at a constant flow rate of 10 MGD. The water has a pH of 7.5 and a temperature of 10°C. Tracer studies have shown a contact time (T10) for the treatment plant to be 30 minutes. The plant maintains a chloraminated residual of 1.2 mg/L. Does the plant meet CT compliance for Giardia? The first step should be setting up the table and identifying the CT Tables to use to find the required CT values. This particular problem uses CT Tables C-3 and C-10 (your instructor should hand these out in class). Remember to subtract out the 2.5 Log credit for conventional treatment. Location and Type of Disinfection Actual CT Required CT CT Ratio Pipeline (free chlorine) 21 mg/L · min Plant (chloramines) 310 mg/L · min Now, the actual CT needs to be calculated. Volume of the 9,000 feet of 3-foot diameter pipe. • Volume = 0.785 x 3ft x 3ft x 9,000ft x 7.48 gal/ft3 = 475,616 gallons • Flow rate = 10 MGD = 6,944 gpm • Dt = 475,616 gal/6,944 gpm = 68.5 minutes • 0.4 mg/L x 68.5 minutes = 27.4 mg/L · min (this is the CT through the pipeline) CT for the plant is: • 1.2 mg/L x 30 minutes = 36 mg/L · min (this is the CT through the plant) Now finish populating the table: Location and Type of Disinfection Actual CT Required CT CT Ratio Pipeline (free chlorine) 27.4 mg/L · min 21 mg/L · min 1.3 Plant (chloramines) 36 mg/L · min 310 mg/L · min 0.12 The sum of the CT ratios equals 1.42 mg/L · min. Therefore, CT is met. You may have noticed that CT was achieved through the pipeline only and the chloramination through the plant is not needed. This is true. So, when solving one of these problems, once you meet the ratio of 1.0 or greater, CT is met and you can stop solving the problem.

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/07%3A_CT_Calculations/7.01%3A_How_Much_For_How_Long.txt

Pressure Pressure is the amount of force that is “pushing” on a specific unit area. Well, what does this mean? When you turn on your water faucet or shower you feel the water flowing out, but why is it flowing out? Water flows through pipes and out of faucets because it is under pressure. It could be that a pump is turned on in which case the pump and motor are providing the pressure. More commonly, the pressure is being provided by water being stored at a higher elevation. Pressures are usually expressed as pounds per square inch (psi), but they can be expressed as pounds per square foot or pounds per square yard as well. The key is that the force is expressed per unit area. Typically, water operators will measure pressures with gauges and express the unit answer as psig. The “g” is this case represents gauge. However, it is also common to express pressure in feet. Feet represent the height of the water in relation to the location that the pressure is being measured. There are two commonly used factors to convert from feet to psi and vice versa. For every foot in elevation change, there is a 0.433 change in psi. Conversely, for every one psi change, there is a 2.31 foot in elevation change. 1 foot = 0.433 psi 2.31 feet = 1 psi As previously discussed, the density or weight of water is approximately 8.34 pounds per gallon. Using this conversion factor, the actual force exerted by the water can be calculated. Example The pressure at the bottom of both tanks in this example is the same. This is due to the fact that the heights are equivalent and pressures are based solely on elevation. However, the force exerted on the bottom of the tanks is dramatically different. The “force” is based on the actual weight of the water. • Pressure = 30 ft x 0.433 psi/ft = 13 psi or 30 ft ÷ 2.31 ft/psi = 13 psi • Force = the volume of water (in gallons) in each tank multiplied by 8.34 lb/gal • Left Tank = 0.785 x 10 ft x 10 ft x 30 ft x 7.48 = 17,615 gallons • 17,615 gallons x 8.34 lb/gal = 146,912 pounds of force • Right Tank = 0.785 x 40 ft x 40 ft x 30 ft x 7.48 = 281,846 gallons • 281,846 gallons x 8.34 lb/gal = 2,350,599 pounds of force Exercises Solve the following pressure and force related problems. 8.02: Head Loss As water travels through objects including pipes, valves, and angle points, or goes up hill, there are losses due to the friction. These losses are called “friction” or head loss. There are published tables listing head loss factors (also termed C factor) for pipes of differing age and material, different types of valves and angle points, etc. However, in this text, we will focus on the theory more than the actual values. Example If water is traveling through 10,000 feet of pipe that has head loss of 3 feet, passes through 4 valves that have head loss of 1 foot for each valve, and passes through 2 angle points that have head loss of 0.5 feet each, calculate the total head loss. • Answer: 3 feet + 1 foot + 1 foot + 1 foot + 1 foot + 0.5 feet + 0.5 feet = 8 feet Summing all of the head loss values yields the answer. In distribution systems, water is pumped from lower elevations to higher elevations in order to supply customers with water in different areas termed zones. Water is also pumped out of the ground through groundwater wells and from treatment plants throughout the distribution system. As water makes its way through the distribution system head loss is realized (as mentioned in the previous paragraph) and pumps must also overcome the head loss from the elevation changes. The diagrams below help illustrate the differences between suction lift and suction head. Suction lift requires more work by the pump to move the water from point A to point B. Suction head provides some help (head pressure) to get water from point A to point B. Exercises Solve the following problems.

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/08%3A_Pressure_Head_Loss_and_Flow/8.01%3A_Are_You_At_a_Loss.txt

Flow rate is the measurement of a volume of liquid (i.e., water) which passes through a given cross-sectional area (i.e., pipe) per unit in time. In the waterworks industry, flow rates are expressed in several different units. The most common ones are shown below. • Flow Rates • cfs = cubic feet/second • gpm = gallons/minute • MGD = million gallons/day Depending on the application, flow rates are expressed in these or potentially other units. For example, the flow rate from a well or booster pump is commonly expressed as gpm, whereas annual production might be expressed as acre-feet per year (AFY). However, when solving a problem for flow rate the common unit of expression is cfs. The reason for this is in part due to the measurement of unit area of the structure that the water is passing through (i.e., pipe, culvert, aqueduct, etc.) The areas for these structures are typically expressed as square feet (ft2). In addition, the speed (distance over time) at which the water is flowing is commonly expressed as feet per second. The flow rate formula and how the units are expressed are shown in the example below. • Flow Rate = Area x Velocity • Flow Rate (Q) = Area (A) x Velocity (V) • Q = A x V • Q (cubic feet/sec) = Area (ft2) x Velocity (feet/sec) Understanding flow rates and velocities can help with the design on pipe sizes for wells, pump stations, and treatment plants. With the understanding that velocities are typically in the range of 2 – 7 feet per second and the known flow rate, pipe diameters can be calculated. For example, if a new well is being drilled and the pump test data determines that the well can produce a specific flow, let’s say 1,500 gpm, and you do not want the velocity to exceed 6.5 fps, the required diameter of the pipe can be determined (see below). Example Q = A x V or for this example A = Q/V since the flow rate (Q = 1,500 gpm) and velocity (V = 6.5 fps) are known. The first step is to make sure the “known” values are in the correct units. Velocity given at 6.5 fps is in the correct unit. However, the flow rate given in gpm needs to be converted to cfs. • 1,500 gpm ÷ 448.8 = 3.34 cfs Now that both values are in their correct unit, divide the two to get the unknown value, in this case, the Area (A). • 3.34 cfs/6.5 fps = 0.51 ft2 Knowing that the Area is 0.51 ft2 and that the formula for Area is 0.785 x D2, the diameter of the pipe can be calculated. • 0.51 ft2 = 0.785 x D2 • D2 = 0.51 ft/20.785 • D2 = 0.66 ft2 In order to find the value of the diameter (D), you must take the square root of D2. • D2 = 0.66 ft2 • D = 0.81 ft Since pipe diameters are typically expressed in inches, multiply the answer by 12. • 0.81 ft x 12 in = 9.7 or 10 inches Exercises Solve the following problems. 9.01: It's All Underground Well Yield Well Yield is the amount of water a certain well can produce over a specific period of time. Typically well yield is expressed as gallons per minute (gpm). During the drilling of a well, pump tests are performed to determine if the underlying aquifer has the ability to supply enough water. A well yield test involves a comparison of the maximum amount of water that can be pumped and the amount of water that recharges back into the well from the surrounding aquifer. Continuous pumping for an extended period of time is usually performed and the yield is calculated based on the amount of water extracted. Well yields are typically measured in the field with a flow meter. Water levels in the well are then measured to determine the specific capacity and drawdown of the well. Specific Capacity Specific Capacity is helpful in assessing the overall performance of a well and the transmissivity (horizontal flow ability) of the aquifer. The specific capacity is used in determining the pump design in order to get the maximum yield from a well. It is also helpful in identifying problems with a well, pump, or aquifer. The specific capacity is defined as the well yield divided by the drawdown, expressed as gallons per minute per foot of drawdown. • Specific Capacity = gpm/ft Drawdown In order to understand the term drawdown, you must also understand static water level and pumping water level as these measurements provide valuable information regarding the well and underlying aquifer. The static water level is defined as the distance between the ground surface and the water level when the well is not operating. The pumping level is defined as the distance between the ground surface and the water level when a well is pumping. Therefore, the pumping water level is always deeper than the static water level. The difference between these two levels is the drawdown. Depending on the aquifer, static water levels can be 20 feet below ground surface (bgs) or several hundred feet bgs. The diagram above shows a well casing penetrating into the ground, the relationship between static and pumping water levels, and the drawdown. Examples Calculating Drawdown • Pumping Water Level – Static Water Level = Drawdown • 50 ft – 20 ft = 30 ft • Drawdown + Static Water Level = Pumping Water Level • 30 ft + 20 ft = 50 ft • Pumping Water Level – Drawdown = Static Water Level • 50 ft – 30 ft = 20 ft Since static and pumping water levels are field measurements, drawdown is typically the calculated value. Calculating Specific Capacity Once you have the drawdown, the specific capacity of the well can be calculated, as long as you know the well yield. Flow Rate = 1,000 gpm Drawdown = 30 ft Specific Capacity = 1,000 gpm/30 ft = 33.3 gpm/ft Exercises Solve the following problems.

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/08%3A_Pressure_Head_Loss_and_Flow/8.03%3A_Flow_Rate.txt

Previously in this text, we discussed the theory of pressure in both feet (head pressure) and psi (pounds per square inch.) In this chapter, we will look at the “power” requirements to move water with pumps and motors. How does water get to the customer’s home? Water pressure is typically provided to customers from elevation (above ground tanks, reservoirs, elevated storage tanks, etc.) But, how does the water get to these storage structures? This is where the concept of horsepower comes in. Historically, the definition of horsepower was the ability of a horse to perform heavy tasks such as turning a mill wheel or drawing a load. It wasn’t until James Watt (1736‐ 1819) invented the first efficient steam engine that horsepower was used as a standard to which the power of an engine could be meaningfully compared. Watt's standard of comparing “work” to horsepower (hp) is commonly used for rating engines, turbines, electric motors, and water‐power devices. In the water industry, there are three commonly used terms to define the amount of hp needed to move water: Water Horsepower, Brake Horsepower, and Motor Horsepower. Water Horsepower is a measure of water power. The falling of 33,000 pounds of water over a distance of one foot in one minute produces one horsepower. It is the actual power of moving water. $\text{Water hp} = \dfrac{(\text{flow rate in gallons per minute})(\text{total head in feet})}{3,960} \label{hp}$ The above equation is used to calculate the power needed to move a certain flow of water a certain height. The constant 3,960 is the result of converting the 33,000 ft-lb/min with the weight of water flow. For example, instead of using gallons per minute, pounds per minute would be needed because 33,000 is in foot-pounds. Water horsepower is the theoretical power needed to move water. In order to actually perform the work a pump and motor are needed. However, neither the pump nor the motor are 100% efficient. There are friction losses with each. The horsepower required by the pump (brake horsepower) can be calculated, but the actual horsepower needed looks at the efficiencies of both the pump and the motor. This efficiency is termed the wire-to-water efficiency. The formula below shows brake horsepower and motor horsepower which includes the combined pump and motor inefficiencies. $\text{Brake hp} = \dfrac{(\text{flow rate in gallons per minute})(\text{total head in feet})}{3,960}(\text{pump efficiency %}) \label{bhp}$ $\text{Motor hp} = \dfrac{(\text{flow rate in gallons per minute})(\text{total head in feet})}{3,960}(\text{pump efficiency %})(\text{motor efficiency %}) \label{mhp}$ If the pump and the motor were both 100% efficient, then the resulting answer would be 100% x 100% or 1. Hence, the actual horsepower would be the water horsepower and the equation is not affected. However, this is never the case. Typically there are inefficiencies with both components. • Pump Efficiency = 60% • Motor Efficiency = 80% • 0.6 x 0.8 = 0.48 or 48% efficient As with all water-related math problems, it is important for the numbers being used to be in the correct units. For example, the flow needs to be in gallons per minute (gpm) and the total head in feet (ft). These will not always be the units provided in the questions. The example below demonstrates this concept. Example $1$ What is the horsepower of a well that pumps 2.16 million gallons per day (MGD) against a head pressure of 100 pounds per square inch (psi)? Assume that the pump has an efficiency of 65% and the motor 85%. Solution In this example, the flow is given in MGD and the pressure in psi. The appropriate conversions need to take place before the horsepower (hp) is calculated. • 2.16 MGD ÷ 1440 min/day = 1,500 gpm • 100 psi x 2.31 ft/psi = 231 ft Now, these numbers can be plugged into the hp formula (Equation \ref{mhp}). $\text{hp} = \dfrac{(1,500\, gpm)(231\, ft)}{3,960}(65 \%)(85\%) \nonumber$ Make sure to convert the efficiency percentages to decimals before solving. \begin{align*} \text{hp} &= \dfrac{(1,500 \,gpm)(231 ft)}{3,960}(0.65)(0.85) \[4pt] &= 158 \,hp \end{align*} Exercises Calculate the required horsepower related questions. 10.02: Head Loss and Horsepower As discussed in Section 8, suction pressure can either be expressed as “lift” or “head.” In other words, the location of the water on the suction side of the pump can either help or hinder the pump. Recall the example diagrams from an earlier section. The diagram on the left (suction lift) requires work from the pump to bring the water up to the pump and then additional work to bring the water to the reservoir above the pump. The diagram on the right (suction head) receives “help” from the tank on the suction side and the pump only has to lift water the height difference between the two tanks. When calculating horsepower, the total head pressure (suction lift + discharge head) or (discharge head – suction head) needs to be calculated. Exercises Calculate the following horsepower related questions. 10.03: Calculating Power Costs It is important for water managers to determine the potential costs in electricity for pumping water. Units used for measuring electrical usage are typically in kilowatt-hours (kW-Hr). In order to convert horsepower to kilowatts of power, the following conversion factor is used. 1 horsepower = 0.746 kilowatts of power Once you know the hp that is needed you can then determine the amount of kW-Hr needed. Then, costs can be determined depending on what the local electric company charges per kW-Hr. Water utilities will calculate estimated budgets for pumping costs since these are typically the largest operating costs. Exercises Solve the following problems. Pump Flow Rate Hp Efficiency Run Time Total Cost 1 500 gpm 50 2 1,000 gpm 75 4 2,000 gpm 250 Well Flow (gpm) Run Time (Hr/Day) Wire-to-Water Eff Head Pressure (psi) hp Cost/Year (\$) @ \$0.135/kW-Hr A 750 18 68% 110 B 1,800 13 61% 85 C 2,750 12 57% 95

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/10%3A_Horsepower_and_Efficiency/10.01%3A_The_Power_of_Water.txt

Community water use is often expressed as gallons per capita per day (gpcd). The term “per capita” is the same as per person. How much does one person use each day? In general, an average person uses water daily to take a shower, use the restroom, cook, drink, wash dishes and clothes, brush teeth, wash hands, etc. The amount of water consumed/used can be estimated if certain assumptions are made. For example, it can be assumed that a typical shower head has a flow rate of 5 gallons per minute and each individual takes one shower per day. A toilet might use 2 gallons per flush and each person is assumed to use the restroom three times per day. An efficient dish and clothes washer might use 7 gallons and 20 gallons respectively. Brushing teeth, washing hands, drinking, and cooking might add up to 2 gallons. You can see that the typical amount of water usage can then be calculated rather quickly. These values are typical for efficient usage. Older toilets and appliances can use several times the amount of water use. The table below gives some examples of efficient and non‐efficient indoor water usage by appliance or device. The units are in gallons. Toilet Conventional Low-Flow Ultra Low-Flow 5.0 3.5 1.6 Washing Machine Conventional Efficient Front Load 37.0 26.0 21.0 Dishwasher Conventional Efficient 18.0 6.0 Shower Heads Conventional Low-Flow 5.0 2.5 Faucets Conventional Low-Flow 3.0 2.5 Although these values can add up to significant daily usage, the primary household water use can be attributed to landscape irrigation. Due to a combination of climate and lifestyle, Californians can use up to 70% of their household water consumption on landscape irrigation. Depending on the size of the actual landscaped area the water usage will vary dramatically and the gpcd will closely follow. Conversely, the national average water use for landscape irrigation is much lower at approximately 30%. Utilities don’t usually go into this much detail in calculating gpcd. Some utilities look at the entire water used in one year and compare it to the total population served. This can provide an adequate answer, but if the utility provides water to large commercial or industrial customers the gpcd can be skewed. Usually, a utility will only look at residential water usage and estimate the total population. Regardless of the process, the per capita water use is expressed as the amount of water used per person per day as indicated in the following formula: • gpcd = water used (gpd)/total number of people Remember, the total number of people represents the population you are observing. For example, if it is a house of 5 people then the total number of people would equal five. In addition, if you are looking at the total amount of water used in one year, it is probably represented as acre‐feet per year (AFY), in which case it would need to be converted to gallons per day. In 2009 Senate Bill SBx7‐7 was signed into law. It requires California water utilities to reduce water consumption in urban water use by 20% by the year 2020. This has prompted utilities to implement water conservation strategies such as high-efficiency appliance rebate programs, various other incentives, tiered water rates, and water budget-based water rates. All of these programs are designed to help reduce water use. Calculating gpcd is extremely important for water utilities, especially in California, or any other area where water conservation is needed or more importantly mandated. Exercises Solve the following problems.

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/11%3A_per_Capital_water_Usage/11.01%3A_How_Much_Water_Do_We_Really_Use.txt

Dilution is not the solution to pollution, but dilution can be used to reduce the level of a contaminant in drinking water supplies. Blending water sources of different water quality is common practice. However, when a water utility wants to blend sources of supply to lower a certain contaminant to acceptable levels they must receive approval from the governing Health Department. A Blending Plan must be created that specifies what volumes of water from each source will be used and what the expected resulting water quality will be. In addition, a sampling strategy must be included in the plan. The Health Department may not allow blending for all contaminants. For example, the local health agency may not approve a blending plan for a contaminant that poses an acute health effect or is deemed to be too high of a risk to public health. An acceptable blending plan may be for reducing manganese in a source that has exceeded the California Secondary Maximum Contaminant Level (MCL) of 0.05 mg/L. Manganese causes black water problems for customers at levels over the secondary MCL. Additionally, an approved blending plan may involve a Primary MCL for nitrate. Nitrates above the MCL of 45 mg/L as NO3 can cause methemoglobinimia in infants under 6 months old. These are just two examples of blending plans. How are blended water quality results calculated? The blending of water supplies is nothing more than comparing ratios. For example, if 100 gallons of one source was mixed with 100 gallons of another source, the resulting water quality would be the average between the two sources. However, when you mix varying flows with varying water quality, the calculations become a little more complex. Using the diagram below will assist you in solving blending problems. If two sources are to be blended, the water quality data for both sources is known. One of the sources with a poor or high water quality result for a certain constituent will need to be blended with a source that has good or low water quality data. Source A will be the high out of compliance data point and Source B will be the low in compliance data point. Source C is the desired blended result. Typically this value is an acceptable level below an MCL. Once these values are established the ratios of the differences between these numbers can be calculated. For example the ratio of C ‐ B to A ‐ B yields the quantity of Source A that is needed. Therefore in the example below, the quantity of A needed is 37.5%. The same thing holds true for Source B. Simply take the ratio of the difference between the high (A) and desired (C) values and divide it by the difference between the high (A) and low (B) values. However, once you solve for the quantity of one source, simply subtract it from 100% to get the value for the other source. See the example below. It is expected that water quality results can and will fluctuate. It is always a good idea to take the highest result from recent sampling when calculating needed blend volumes to reduce the impacted water to acceptable levels. For example, if a well is being sampled for trichloroethylene (TCE) quarterly and the results are 6 ug/L, 7.8 ug/L, 5.9 ug/L, and 8.5 ug/L from a recent year of sampling, it would be prudent to use the 8.5 mg/L result when calculating blending requirements. It is also important to note that the local health authority should be consulted with respect to any blending plan. This says that 37.5% of Source A is needed and 62.5% of Source B is needed to achieve the desired blended value. Once the percentage of each source has been calculated the actual flows can be determined. Sometimes the total flow from both sources is known. In this case, you would take that known flow rate and multiply it by the respected percentages of each source. In the example below 5,000 gpm is needed. This example demonstrates that Source A can provide 1,875 gpm of a supply that has a water quality constituent result of 10 ppm and Source B can provide 3,125 gpm of a supply that has a water quality constituent result of 2 ppm to achieve a total flow of 5,000 gpm with a resulting water quality result of 5 ppm. This is just one example of how this equation can be used to calculate the answer. Another example is where the flows and the existing water quality results are known and the utility must calculate what the desired result will be. In any of these examples, if the process above is followed, the resulting answers can be calculated. Exercises Solve the following blending problems. 12.02: Mixing and Diluting Solutions Another common process with chemicals is the mixing of solutions with different strengths, or diluting a certain chemical concentration strength with water. Let’s look at a dilution based example first. • If 700 mL of water is added to 250 mL of a 65% concentration strength solution, what is the resulting concentration strength? In the above example, the resulting volume is 950 mL. This is calculated by adding 700 mL to 250 mL. The formula used to calculate the new concentration strength is the following: • C1V1 = C2V2 • 0.65 x 250 mL = C1 x 950 mL The left side of the equation becomes 162.5 and this is divided by 950 mL to get the diluted concentration strength. • 162.5950 = 0.17 or 17% This says if 250 mL of a 65% solution is diluted with 750 mL of water, the resulting concentration will be 17%. By mixing two solutions of different strengths and known volumes the resulting strength can be calculated. Let’s look at the following example. • 700 mL of a chemical with a concentration strength of 25% is mixed with 250 mL of 65% concentration strength. What is the resulting concentration strength? In the example above, the resulting volume is 950 mL. This is calculated by adding 700 mL and 250 mL.

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/12%3A_Blending_and_Diluting/12.01%3A_Is_Dilution_the_Solution_to_Pollution.txt

SCADA is the acronym for Supervisory Control and Data Acquisition. It is a computerized system allowing a water system to operate automatically. A SCADA system usually consists of three (3) basic components: field instrumentation, communications (telemetry), and some type of central control equipment. The field instrumentation will measure various parameters such as, flow, chemical feed rates, chemical dosage levels, tank levels, etc. These instruments will then gather a series of signals and transmit them through some type of communication device(s) known as telemetry. The telemetry communication can be radio signals, telephone lines, fiber optics, etc. This information is sent to a central control computer typically located at an office or operations control center. This computer will have software interpreting the signals and displaying the actual values of the parameters being measured. Below is an example of a typical SCADA computer screen. A common measurement used to analyze the various field parameters of a water system is the 4-20 milliamp (mA). A 4-20 mA signal is a point-to-point circuit and used to transmit signals from instruments and sensors in the field to a controller. The 4 to 20 mA analog signal represents 0 to 100% of some process variable. For example, this 0 to 100% process variable can be a chlorine residual from 0.2 to 4.0 mg/L or a tank level of 0 to 40 feet. The 0% would represent the lowest allowed value of the process and 100% the highest. These mA signals are then sent through the SCADA system and processed into understandable values such as mg/L or feet, depending on the parameter being measured. This first example is using the 4-20 mA signal to measure the level of water in a storage tank. The tank is 40 ft tall and has a diameter of 30 ft (not to scale). There are a couple of things to point out with storage tanks. First, although the height of the tank is 40 ft, the water is never filled to that height. Why? Because the inside roof of the tank would be damaged. Therefore, all storage tanks have an “overflow” connected at the top of the tank off to the side. The second thing to point out is that the “bottom” or zero level of the tank is never at the actual bottom of the tank. Why? Because you never want to run a tank empty. There is always a several foot distance from the actual bottom to what is referred to as the “zero” level. In many questions, the “overflow” (actual top-level) and the “bottom” (actual location of the zero level) will be mentioned. Therefore, in this example above since there is no reference to an overflow or where the zero level is located, the 4 mA signal would represent 0 ft and the 20 mA signal 40 ft. What this is saying is if your meter sends out a signal of 20 mA, then the corresponding level in feet would be 40. Likewise, if the signal was 4 mA the corresponding level would be 0 ft. What do you expect the mA reading to be if the tank was half full (20 ft)? If you initially thought 10 mA that would be a logical guess. However, let’s think about this for a minute. Since the bottom or 0 ft is at 4 mA and the top or 40 ft is at 20 mA, the span, or difference between 4 and 20, is only 16, not 20. This “span” is an important number when solving these problems. Now, if your second guess was 8 mA that would be a logical answer too, but it is also an incorrect response. Yes, 8 is half of 16, but we are not dealing with a span of 0 - 16, we are dealing with a span of 4 - 20. Therefore, half of 16 is 8, but the halfway distance between 4 and 20 is 12! Anyone who guessed 12 mA, give yourself a hand. Whatever read you have on your meter, you must subtract out the 4 mA offset. Once you understand this the equation is quite simple. The meter read minus the offset divided by the span equals the percent of the value being measured. • (mA (reading) - 4mA (offset))/ 16 mA (span) (20 - 4) = percent of the parameter being measured Let’s use the 40 ft tank example to illustrate the solution. In a 40 ft tall tank, a 10 mA reading was collected for the height of the water level in the tank. • (10mA (reading) - 4mA (offset))/16 mA (span) = 6 mA/16 mA = 0.375 or 37.5% full If the tank is 37.5% full then multiply this percentage by the total height. • 0.375 x 40 ft = 15 ft

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/13%3A_Supervisory_control_and_data_acquisition_(SCADA)_and_the_Use_of_mA/13.01%3A_SCADA.txt

Every water utility has a management staff that directs, plans, organizes, coordinates, and communicates the direction of the organization. But, what does this mean? It means that managers do a variety of functions that sometimes go unnoticed and at times can be difficult to measure. However, one important function of utility managers is financial planning. Managers are responsible for preparing budgets, working on water rate structures, and calculating efficiencies within the organization. Budgets How much money does a utility need to perform the routine, preventative, and corrective action maintenance items? How much money is needed to operate the utility? How much needs to be spent on Capital Improvement Projects? Does the utility have any debt to pay off? How much are salaries, benefits, etc., etc., etc.? These are some of the main items that managers look at when determining budgets. Many times budgets are not only prepared for the upcoming year. Frequently utilities will look 5, 10, even 20 years into the future for budgetary analysis. Let’s define some of these budget items. Operations and Maintenance (O&M) These two items typically go hand and hand. There are certain costs that the utility must cover and must properly budget for in order to keep the water flowing. Chemical costs for treating water, repairs on vehicles and mechanical equipment, power costs to pump water, leak repairs, and labor are just a few of the items that fall under this budgetary classification. Some are known, such as labor (salaries), as long as overtime isn’t too large. Others are predictable, such as power and chemicals. Based on historical water production, power and chemicals can be predicted within a reasonable amount of accuracy. Others, like water main breaks can be estimated based on history, but other factors come into play such as age, material, location, pressures, etc. Regardless of the predictability of O&M costs, managers must come up with an accurate budget number and then make sure that number is covered with revenue. Capital Improvement Projects (CIP) In addition to the reoccurring O&M costs, utilities need to plan and budget for future growth and the replacement of old infrastructures, such as pipelines and storage structures. Depending on the age of the utility and the expected future growth, CIP investment can be quite extensive. Typically, utilities can recover the costs of new infrastructure from the developers that are planning to build within the utilities service area. However, as infrastructure ages, it eventually needs to be replaced. The timing and funding of these replacements is an important part of a manager’s responsibility. Debt More times than not, utilities will take on large amounts of debt to cover major capital improvement projects. Debt is used by utilities as a way to keep water rates lower. If a utility were to cover the cost of replacing major infrastructure projects through rates, the water rate could be too high for many people to pay. With a proper debt structure, the utility can spread out the costs over many years to help keep rates lower. Revenues and Rates In order for water utilities to pay for all their expenses (i.e., pumping, chemicals, material, salaries, benefits, etc.) they need to collect enough money. This is known as Revenue Requirements. A utility must identify all revenue requirements and then identify the means for collecting this revenue. Utilities can have different revenue sources such as property taxes, rents, leases, etc. However, most water utility revenues are collected through the sale of water. The cost of water is determined through a Rate Study. A rate study is a report that lists the revenue requirements and then calculates how much the rate of water needs to be to collect these requirements. Water rates can be set in a variety of different structures (flat rate, single quantity rate, tiered rate, etc.), but regardless of the structure, the utility must sell water at the calculated rate to recover the needed revenue. Efficiencies As part of the budgetary process, managers need to identify if and when certain pieces of equipment will fail. Calculating the return on investment and identifying when the cost of maintenance exceeds the cost to replace the asset is crucial. An example of this is looking at the efficiencies of pumps and motors. Over time the efficiency decreases and the cost to operate and maintain the pump and motor increases. Another example is with pipelines. As pipes age more and more leaks occur. At some point in time, the cost to repair leaks becomes greater than the cost to replace the pipe. Now that these topics have been loosely defined, let’s take a look at how it all works mathematically. The table below demonstrates some O&M numbers for a typical small utility. Example Exercise O&M Item Monthly Averages Cost per Unit or Number Monthly Cost Annual Cost Water Production Groundwater Purchased Water 440 MG 190 MG \$230 \$1,200 \$101,200 \$228,000 \$1,214,400 \$2,736,000 Staffing Hourly Employees Salary Employees Benefits \$3,500 \$6,200 40% of Pay 15 10 \$52,500 \$62,000 \$45,800 \$630,000 \$744,000 \$549,600 Chemicals Chlorine (1.5 ppm) 5,504 lbs \$2.70 \$14,860 \$178,330 Vehicle Maintenance \$250 17 \$4,250 \$51,000 Leaks and Repairs (Materials Only) \$2,500 3 \$7,500 \$90,000 Pumps and Motors (Materials Only) \$1,000 6 \$6,000 \$72,000 Treatment Equipment \$75 8 \$600 \$7,200 Miscellaneous \$1,125 NA \$1,125 \$13,500 TOTAL \$523,836 \$6,286,030 Using the information provided in the table above, fill in the information in the table below. O&M Item Percentage of Annual Budget Water Production GW & Purchased Staffing Salary & Benefits Chemicals Vehicle Maintenance Leaks and Repairs (Materials Only) Pumps and Motors (Materials Only) Treatment Equipment Miscellaneous Think about which items are controllable and which would be considered fixed costs. List the fixed costs versus variable costs and give an explanation justifying your response. Some might seem fixed, but there are ways to look at them as a variable cost. Others might seem like a variable cost, but in reality, there is limited control of the cost and would be considered fixed. • Fixed Costs Reason: • Variable Costs Reason: Discussion Although the cost of water is “fixed” sometimes water utilities can control the amount that is purchased versus the amount that is pumped from wells. Buying water from another entity can be quite costly. However, more information would be needed about the utility to understand their production flexibilities. Staffing and benefits would also be considered a “fixed” cost, but staffing reductions or adjustments in benefits could also occur. There are certain fixed vehicle expenses, such as oil changes, tune ups, tires, etc. There are also some unknown maintenance issues such as a bad battery, a faulty water pump, etc. All of these examples can be looked at as fixed or variable costs. The idea is not to “pigeon hole” these expenses as fixed or variable. The idea is to be able to accurately estimate these and other expenses in a budget. It is extremely important that utility managers have a general understanding of the concepts associated with utility management as well as the mathematical computations necessary to support the budgetary decisions being made. The exercises in Chapter 13 provide some basic examples of utility budgeting practices. Exercises 1. Will the vehicle cost more than 60% of a new vehicle cost before reaching 150,000 miles?

textbooks/workforce/Water_Systems_Technology/Water_131%3A_Advanced_Water_Mathematics_(Alvord)/14%3A_Water_Utility_Management/14.01%3A_Managing_With_Numbers.txt

In Part One of this text, we’ll explore the basics of water supply and demand. We’ll review the water cycle, explore basic concepts in water management, introduce surface water and groundwater rights, and then introduce the ideas of stakeholders in water projects. Part One is divided into these four sections: • The Water Cycle • Water Management Concepts • Water Rights • Stakeholder Concepts For many of you, the Water Cycle will not be a new concept. But now you will need to frame it differently. Rather than considering it as a scientific concept, you'll have to see the interface between science and society and between supply and demand. Water management concepts will take the water cycle further as you learn how different sources of groundwater and surface water supplies are identified and used both separately and together. There are benefits and drawbacks to each type of source of water. Water rights are important to all aspects of the water supply. While we can't make you an attorney, you'll understand the basic types of water rights in California by the end of this section. And lastly, in Part One, you'll finish with an examination of typical stakeholders in different water issues. Stakeholders aren't just a concept from business theory. They are critical to how we get things done in the water industry. You'll look at a few real-life examples of the consequences of working with (or neglecting) stakeholders in the water industry. Thumbnail: Hydraulic Gold Mining by Carlton Wakins. (Public Domain) 01: Water All Around Us Learning Objectives After reading this section, you should be able to: • Identify processes in the water cycle that influence the water supply • Analyze situations in terms of precipitation, condensation, evaporation, and transpiration • Evaluate yearly data for evapotranspiration You've probably heard on the news the statewide water supply in California described in terms of snowpack and rainfall. These are critical measures of how much water is available for human use. Water managers in California follow both snowpack measurements and rainfall measurements closely. In the diagram above from the United States Geological Survey (USGS), you can see that precipitation is shown as rainfall and snow. Precipitation also includes something you don’t see too often in California: hail and sleet. All forms of water that fall from the sky, including rain, snow, hail and sleet, are forms of precipitation. Rainfall can provide much needed water in the ground by the process of infiltration, the process by which water seeps into the ground and eventually recharges our groundwater, water stored in the ground. Using the diagram above, you can also trace the flow of groundwater in some cases to both rivers, lakes, and even to the ocean. Above ground, rainfall can also be stored on earth’s surface in lakes. Precipitation in California also provides snow for snowpack, which can be our largest area of storage of water in the winter. In fact, it is common for water managers to view the snowpack in the Sierra as a reservoir; it is simply a seasonal reservoir that melts in the spring. Snowmelt runoff from the snowpack can fill streams and lakes. Runoff from rainfall is also captured in streams and lakes and can serve to recharge aquifers through percolation and infiltration. The diagram also shows the key process of evaporation, or the process through which liquid water turns into a gas. Evaporation occurs over bodies of water like the ocean or lakes, but also over the land. If you own a home with a pool, you have probably noticed that if you leave the pool without a cover in the summer, you have to add water more often in the summer than in the winter. This is because the rate of evaporation is higher in the summer than the winter, often dramatically so. Transpiration is the process through which plants lose water. This may seem like an inconsequential process, but it is the entire process that drives irrigation. In the diagram below you can follow the transpiration process. In Step 1, plants bring in moisture from the soil with their roots. Then, in Step 2, water travels up through the plant. In Step 3, water leaves through their pores or stomates (plural of stomata) and enters the atmosphere again. The combination of water loss from liquid water in the ground evaporating and water in plants losing water is called evapotranspiration (ET). Evapotranspiration is frequently used by scientists as a measurement of the plant water needs. If a location has a high ET, then the plant needs are greater than a location with a low ET. Most locations in the state of California are close to a weather station that is part of the California Irrigation Management Information System (CIMIS) network. A CIMIS station measures a variety of variables in order to calculate the ET including: temperature, solar radiation, humidity, wind speed, and wind direction. With a complicated formula, the CIMIS station will calculate the ET for a specific geographic location. This information is frequently used to make a water budget, an estimate of how much water a location should use, including outdoor watering based on the amount of landscaping, the type of landscaping and the evapotranspiration. The monthly inches of ET data in the table for Santa Clarita reflects the water needs in terms of inches of water that grass would need to receive per month. You can see that the highest needs are in summer, primarily July and August, with needs decreasing rapidly in September through December. Even though September is typically almost as hot as August, the days are shorter and the sun is less intense so the evapotranspiration is less in September than August. This means the plant needs for irrigation are significantly less. CIMIS Station #204 Santa Clarita - 2016 Evapotranspiration Data Months Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Monthly ET (in) 1.97 4.80 4.51 5.24 5.77 7.77 8.99 8.13 6.30 4.68 3.40 2.69 Knowledge of evapotranspiration has a practical application - in Southern California, many people find they can turn off their irrigation systems for grass in normal years from November through February and that their plants’ water needs will be met with rainfall alone. The opposite process of evaporation is condensation, the process through which water as a gas turns into liquid water again. Condensation is the process through which clouds form. This is also the process through which water beads on the outside of a glass of iced tea on a humid day or on a mirror in a steamy bathroom. In terms of the water supply picture, condensation is the key process that can lead to precipitation, so clouds are carefully monitored by scientists. What makes the water cycle work? In short, gravity and the sun. Notice that there is always groundwater flow and streamflow from a higher altitude to a lower altitude. Gravity drives this flow of water in the water cycle, and is also a key force in most water distribution systems. If you’re not using gravity, you’re going to need a pump to go from a lower elevation to a higher elevation. Systems are generally designed to avoid pumps if possible and use the force of gravity. The sun drives the water cycle in a different way, by heating the water and causing it to evaporate. It also melts the snowpack in the mountains while gravity causes the water to flow into streams, rivers and lakes. In Section 1.1, you've learned the basic processes in the water cycle: precipitation, infiltration, evaporation, transpiration, and condensation. Next, you'll see how these processes create surface and groundwater supplies and how these supplies are used for water management. Try It! Describe a process at work in each scenario and how the process works: 1. Analyze the effect on the water cycle if California had no precipitation for a year. 2. You hang a wet swimsuit out on the balcony to dry overnight. What process is at work? How is water changing states? 3. Using the CIMIS web site (www.cimis.water.ca.gov/), register for an account (free). Then under the Data tab, find the nearest CIMIS station to your home create a monthly web report for 12 consecutive months, which should include ET. When should you water the most? When should you water the least? Key Terms Condensation—The process through which water as a gas turns into liquid water again; opposite of evaporation Evaporation—The process through which liquid water turns into a gas; opposite of condensation Evapotranspiration—The combination of water loss from liquid water in the ground evaporating and water in plants losing water Groundwater—Water stored in the ground Infiltration—The process through which water seeps into the ground Precipitation—All forms of water that fall from the sky, including rain, snow, hail, and sleet Transpiration—The process through which plants lose water Water budget—An estimate of how much water a location should use, including outdoor watering based on the amount of landscaping, the type of landscaping and the evapotranspiration

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/01%3A_Water_All_Around_Us/1.01%3A_Water_Cycle.txt

Let's engage in a little thought experiment. If a zombie apocalypse happened right now and you ran for the hills, you would have to find water to survive. How would you go about doing this? In this section, you’ll identify sources of water supply. This section is critical to an understanding of water management, both personally as well as regionally and statewide. Learning Objectives • After reading this section, you should be able to: • Describe various sources of surface and groundwater supply • Give examples of water storage • Evaluate a situation in terms of conjunctive use Now back to the zombie apocalypse. If you had to find water, you would probably: • Try to find a stream or lake • Start digging a well Notice that you didn’t start with the ocean. This is important because most of us intuitively understand the amount of energy it takes to make ocean water drinkable. Although most of the water on earth is in the oceans, bays, and seas, it’s not drinkable without expensive treatment. Who would have time for that level of treatment in the zombie apocalypse? And you also didn’t start with the ice caps (too far and too many zombies in the way). What you have intuitively chosen is the right solution—surface water and groundwater. And your strategy reveals another challenge for water managers—most of the water on earth is not accessible or easily potable (drinkable). Most of the water on earth is in the ocean (97%). For the 3% that remains as freshwater, most of it is trapped in glaciers and ice caps (68.7%). That leaves only groundwater and surface water making up less than 1% of the water on earth. You can see why people refer to water as precious! In fact, 20% of all freshwater on earth is in one enormous lake in Russia, Lake Baikal, which is inaccessible to most of us on earth. Surface water can be broken into different types, but it is easiest to think of surface water as either bodies of water and flowing water. Surface water can occur as a lake or pond, both bodies of water at low places in the land where water has accumulated. Most lakes have both inflow and outflow. Some lakes lack inflow and/or outflow and they become salty over time (e.g., Great Salt Lake, Dead Sea, Salton Sea). A reservoir is a lake that is manmade by making a dam across a river. Surface water can be flowing water, such as a creek, stream, or river. It can also be water stored in a lake or reservoir. People tend to use the terms creek, stream or river interchangeably. Rivers (or streams or creeks) form when water moves from higher ground to lower ground. You’ll remember that in the water cycle, gravity is a driving force—all water flows downhill. When water falls from the sky as rain in the water cycle, it may infiltrate into the ground, but it also may run off and form creeks and streams. Eventually, creeks, streams and rivers flow to the ocean. As a source of water, surface water has both benefits and drawbacks. Benefits of Surface Water Drawbacks of Surface Water Easy to access Water is lost to evaporation Lakes and reservoirs can provide flood control in addition to a water supply Lakes and reservoirs may experience a build-up of sediment, especially after fires Distribution requires a network of pipes and/or canals Well, nothing is perfect in the study of water supply. If surface water isn’t the perfect supply, perhaps groundwater is better. In the diagram below, you can see both surface water and groundwater. The water table is the line at which soil becomes saturated with water. The soil above the water table is unsaturated and the water below the water table is saturated. Groundwater is stored in aquifers, which are areas underground of soil or rock that can hold and transmit water beneath the water table. Misconception Alert! Frequently, people will describe an aquifer as an underground swimming pool. While this does illustrate the idea that water is stored underground, it is really misleading. A swimming pool contains water entirely. An aquifer is mostly sediment or rock with water in the pores between grains of rock or sediment. Sediment and rock vary in terms of how much water it can store. The ability for rock to transmit media is often referred to as permeability. Sometimes gravel has large pores and rock has large connected fractures that enable water to move through them. Other times, the pores in gravel and the fractures in rock are impermeable. In order to get water from the aquifer to the surface, you need either the water to come up from the ground naturally because of pressure in the layers confining the aquifer or you need to drill a well, which is much more common. In the diagram below, you can see the difference between a deep well and a shallow well. When the water table is at a normal level, both the shallow and deep well can produce water. However, when it is a drought, only the deep well can reach below the water table. The shallow well would end up being dry. Groundwater as a water supply also has benefits and drawbacks that communities consider when they build their water supply portfolios. Groundwater Benefits Groundwater Drawbacks Difficult to pollute Difficult to clean up Useful in times of drought when surface supplies are low Replenishment is slow Generally, cheaper Hard to manage as levels dwindle No need for an expensive network of pipes and canals to transport long distances Visual inspection is difficult Some communities use both surface water and groundwater as a supply. In years of heavy snowfall and deep snowpack, there may be abundant surface water available. In this case, surface water would be used for water supply while groundwater supplies could be allowed to replenish naturally through the infiltration of rainfall. In addition, surface water could be stored in groundwater basins to aid in replenishment. In the reverse situation, in years of light rainfall and little snowpack, groundwater would be relied on as a primary source because surface water was not a sufficient supply. The practice of alternating water supplies to meet the needs in a community is called conjunctive use. Both surface water and groundwater can provide adequate yearly sources of water, but it is best to have water stored for use in dry years or for emergencies. Water can be stored above ground in reservoirs and below ground in banks. Storing water in reservoirs makes it readily accessible in times of drought or emergency, such as fires or if part of a distribution system goes out of service. Storing water in the ground can be done in water banks, such as the banks in Kern County. In these banks, water is injected or infiltrates directly into an aquifer. It can be retrieved later for a fee during times when groundwater and surface water are not sufficient. Many water districts find that storing water in various water banks can diversify their water supply portfolio, giving them more flexibility in providing water in dry years. How can you make your water supply more reliable? Think of the last drought. You probably noticed lower levels in surface water at lakes and reservoirs and even in streams. In the photo comparison, you can see the difference in just over a month's time in 2014 in the visible shoreline. In this example, more water has been taken from the reservoir to treatment facilities during the late spring in 2014 with a very visible effect on the appearance of the lake! In California, typically, it is only through a combination of water supplies that you can have a reliable water supply. The best scenario is that you have a water supply that consists of multiple sources of groundwater and surface water. That way, when one source is dry or less reliable due to a drought or unusable due to a water quality issue, you have a backup. The ultimate scenario for water supply reliability also includes a supply of water in storage. In Santa Clarita, there are multiple sources of water supply for the water retail companies. Sources of supply include relatively shallow groundwater wells into the alluvium, clay, silt, and gravel, as well as deeper groundwater wells into the Saugus formation. While the shallower alluvial wells provide a source of relatively inexpensive supply, they also tend to be more sensitive to droughts. Imported water from the State Water Project makes up roughly 50% of the water supply in a normal year though the amount in this supply relies entirely on the snowpack in the Sierra Nevada Mountains. During the last drought in Santa Clarita when water deliveries from the State Water Project were at a minimum, groundwater pumping was increased above normal year levels. When deliveries from the State Water Project returned to pre-drought levels in 2017, groundwater wells were pumped less in order to let the well levels recover. This is a classic example of conjunctive use that brings together what you've learned about groundwater and surface water because of the alternation of supplies in order to achieve greater reliability. Now that you understand the concepts used to manage groundwater and surface water, let's take a look at water rights in California. Try It! 1. Identify at least three potential sources of water that you could use during the zombie apocalypse. 2. Describe the drawbacks of surface water and groundwater. 3. Many communities in California rely on groundwater and surface water. Explain how conjunctive use might apply. Key Terms Alluvium—Clay, silt, or gravel left from old rivers Aquifers—Areas underground of soil or rock that can hold and transmit water Conjunctive use—Use of alternating water supplies to meet the water demands Permeability—The ability to transmit water Potable—Drinkable water Reservoir—A lake that is manmade by making a dam across a river Surface water—Flowing water, such as a creek, stream, or river; also still river stored in a lake or reservoir Water table—The line at which soil becomes saturated with water

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/01%3A_Water_All_Around_Us/1.02%3A_Water_Management_Concepts.txt

In order to understand the types of water rights that you’ll find in California, you’ll have to take a bit of a trip back in time, not just in California history, but in British history as well. You will be able to apply what you have learned about surface and groundwater. Learning Objectives After reading this section, you should be able to: • Distinguish between surface water and groundwater rights • Describe types of water rights found in California • Analyze a situation involving water rights to determine which rights should prevail You probably recall that California was not always a state within the United States. For many years, it was a settlement of the Spanish government, and later, the Mexican government. Settlements of the Spanish and Mexican governments have pueblo rights to both the surface and groundwater within the settlement limits. These rights are considered to have the highest priority compared to all other right types and cannot be lost. The City of Los Angeles has exercised pueblo rights several times in its history, illustrating interesting features of pueblo rights: 1. A pueblo water right can increase in quantity as the population increases. As the population of Los Angeles has increased, the pueblo water right to flows of the Los Angeles River as well as to groundwater have increased in terms of quantity; 2. A pueblo water right can be extended to newly annexed areas of the original pueblo, such as when the City of Los Angeles annexed the San Fernando Valley You can see how pueblo water rights are extremely encompassing and useful. Pueblo Rights Riparian Rights Exist because of historical affiliation with Spain and Mexico Exist because of streamside location Can increase in quantity based on population or area annexed Not quantified Only beneficial and reasonable use (not wasteful) Shifting continents for a moment, we will explore the idea of riparian rights. In English common law, a riparian right (riparian means “streamside”) is the right to use surface water because you own property that is adjacent to it. This means that if you bought a home that was adjacent to a stream, you would have the right to use the water from it. You could only use the water that was naturally flowing from the stream, not water from upstream or downstream that you channeled into your land. If you lived one street further away and didn’t own any property adjacent to the stream, you would have no riparian rights. Riparian rights are not quantified, so if you owned that house on the stream, you may only use as much water to make reasonable and beneficial use of it. Now taking what you’ve learned about pueblo water rights and riparian rights, let's shift back to California to the mid-1800s when gold mining was thriving. An appropriative right stems from mining practices in which miners worked on public land using the water to dislodge soil to expose gold. Often, water had to be channeled a distance from its origin to where it was used. This was considered an appropriation of water. Miners literally posted a notice about their diversion of water to stake a claim to that water. Whereas riparian rights are not quantitative, an appropriative right is a specific amount of water for a specific purpose in a specific place. If there is not enough water for all appropriators, the ones with the older appropriations get their water first. The most famous legal case involving surface water rights is Lux v. Haggin (1886), which established the existence of both riparian rights and appropriative rights and the relationship between the types of rights. In this case, Haggin owned the upstream Kern Valley Land and Water Company, which diverted water for irrigation. Because Haggin did not own land that was adjacent to the water, he was exercising appropriative rights and not riparian rights. Miller-Lux owned downstream land that was adjacent to the Kern River and exercised riparian rights. During a drought, Haggin continued to use upstream water and cattle owned by Miller-Lux died due to lack of available water. Miller-Lux sued Haggin. The primary question, in this case, was whether an upstream appropriator could divert water in a way that hurt a downstream holder of riparian rights. In a surprising outcome, the California Supreme Court ruled that appropriators (Haggin) could have senior rights if the rights were established prior to downstream riparian use. In Herminghaus v. Southern California Edison (1926), riparian and appropriative rights faced off again. Herminghaus was using riparian rights to irrigate by letting water from the San Joaquin River flood his crops. Southern California Edison wanted to build an upstream power plant using appropriative rights. The California Supreme Court ruled that downstream riparian use had the right to the entire flow of the San Joaquin River for flood irrigation. In other words, the California Supreme Court ruled that the downstream riparian right trumped the appropriative right, which meant Southern California Edison received no water rights. Currently, appropriative rights are governed by a “first in time, first in right” philosophy and regulated by the State Water Resources Control Board. A “first in time, first in right” philosophy means that if you are using the water first, you have seniority in terms of water use. In times of water shortage, you will get your water first. Much like you saw in the previous court cases, you do not need to own the land in order to have an appropriative right to water. However, you do need to use the water in a reasonable and beneficial way with an appropriative right. While surface water rights have hundreds of years of history, groundwater rights are relatively recent and currently changing in California. Currently, in California, the Sustainable Groundwater Management Act is driving the management of groundwater in a much more deliberate fashion. Basins in California have been ranked according to their priority for the development of a groundwater management plan into high, medium, and low priority. Basins with high ranking are currently developing plans for agency formation. Groundwater rights can be overlying or appropriative. Remember your streamside house? It had riparian rights to use water from the stream. You would also own overlying rights and the rights to drill a well and pump water to use water on your own land. If your neighbor behind you wanted to pump water to take the water off of the land, he would be using appropriative rights. Appropriative rights in groundwater are similar to rights in surface water. “First in time, first in right” means that groundwater appropriators are evaluated in terms of when they started using the water. Although groundwater and surface water rights have some of the same names, it is important to note that they are managed as if they are not related. For surface water rights, you can have pueblo water rights if the land was originally a Spanish or a Mexican settlement, riparian rights if you are using the water streamside and appropriative rights if you are using the water away from the source. For groundwater rights, you can have overlying rights or appropriative rights. From studying the water cycle, you already understand that surface water and groundwater are related. It would make sense if their rights were connected rather than treated as separate entities. Try It! 1. You own a home and would like to dig a well in the backyard. What type of water rights would be involved? 2. You would like to run a pipe from your neighbor’s creek to your home to engage in flood irrigation. What types of rights are involved? What issues might come up? 3. When might you have a surge in water rights disputes? Key Terms Appropriative right—Right to move water from its source; quantities for a specific purpose in a specific location; often called “first in time, first in right” rights Overlying rights—Groundwater rights for water underneath the land Pueblo rights—Rights that pueblos and settlements of the Spanish and Mexican government have for surface and groundwater rights; pueblo water rights can increase in quantity as population increases and can be extended to newly annexed areas Riparian right—Streamside right to surface water

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/01%3A_Water_All_Around_Us/1.03%3A_Water_Rights.txt

Who are stakeholders in your water supply? While you might immediately think of your water utility, city or county agencies, you are also a stakeholder in the water supply. You are a resident and you use the water in some fashion (e.g., drinking, cooking, cleaning yourself and clothes, irrigating, and swimming). How much interest do you have in the water supply? And how much power do you wield in critical discussions about water? Learning Objectives After reading this section, you should be able to: • Identify and classify stakeholders • Differentiate among stakeholders according to the level of interest and the level of power Stakeholders are people with a “stake” in an idea or project. These could be people who are financially related to the idea or project, interested in the environmental impacts, or just plain curious. In many nationwide issues, like the presidential election, health insurance, or gasoline prices, all residents of the United States have a “stake.” Some issues are much more regional, such as water supply issues or air pollution issues, in which residents in a smaller geographic area have a stake while some issues, such as health care, are nationwide issues Stakeholders are typically classified as internal or external. An internal stakeholder is a person within an organization, such as a staff person or board member, while an external stakeholder is outside an organization. For example, suppose that staff at a water agency was considering changing the rules for a turf grass removal program, commonly called "Cash for Grass," in order to stop rebating artificial turf. Here is a table of the internal and external stakeholders who have a “stake” in this proposal to remove artificial turf from the Cash for Grass program: Internal Stakeholders External Stakeholders Staff at the water agency Residents in the area Management at the water agency Landscapers (who install plant material) Board members at the water agency Contractors (who install artificial turf) Why is it important to identify stakeholders and categorize them? As you work in the water industry, you will find that reaching out, listening to, and working with stakeholder groups is critical to your success. In the example above, what would happen if staff didn't reach out to contractors who install artificial turf? It's possible that they would become very angry because a potential source of income (installation of artificial turf for rebates) has been taken away from them. They might make phone calls to managers and board members. They might attend board meetings to speak and protest during public comment. Their anger might have been moderated if staff had reached out ahead of time to explain the reason for the rule change and offer some alternative strategies to move ahead. Let's take another example from the water industry. Let's say the customer service manager decided to implement a new software program that sent work orders to field representatives. The customer service manager bought the software with her own manager's approval, but chose not to introduce customer service and field staff to the new product. Instead, the customer service manager rolled out the product at a meeting after the software was purchased. How do you think the staff felt? They may have had valid concerns about the software, but the entire purchase was presented to them like a done deal. The customer service manager should have identified her stakeholders, including internal stakeholders like customer service and field staff, ahead of time. Stakeholders are people very specifically interested in an idea or concept whether it's artificial turf or work order software. Stakeholders are specific to the locale as well as the concept. For example, the City of Beverly Hills developed a cultural plan, which included an extensive list of stakeholder groups: residents, businesses, chamber of commerce, entertainment industry, faith-based communities, fashion community, financial sector, gay community, homeowners associations, Iranian community, lawyers associations, media, private galleries, restaurants, senior community, service clubs, and the tourist industry, including hotels and visitors. A cultural plan for a different city would have different stakeholder groups and, a stakeholder list for a different issue in the same city would have different stakeholders. Let’s look at what would happen if we looked at a different issue, like water supply reliability, and identify internal and external stakeholders in Beverly Hills. Stakeholders who were added to the list are in blue text. Many of the stakeholder groups that were interested in a cultural plan do not appear below because they may not be interested in water supply reliability. Internal Stakeholders for Water Supply Plan External Stakeholders for Water Supply Plan City of Beverly Hills staff Residents City of Beverly Hills management Businesses Beverly Hills City Manager Chamber of Commerce Beverly Hills City Council Environmental Groups Metropolitan Water District (wholesale supplier of water) Homeowners’ Associations (HOAs) Large Residential Users (A Top 100 List) Media Restaurants Tourism & Hotel Industry Visitors The list is by no means all-inclusive, but shows that there are some groups that will be constant in an area because they are powerful (HOAs, tourism & hotel industry, and restaurants) and some groups that are specific to an issue (e.g., Environmental Groups and Top 100 water users). This list is shorter and more focused on where the water is used. Once you have identified your stakeholders, you can arrange them according to their level of interest and power. In terms of water issues, most of the public, most of the time, unfortunately, has a relatively low level of interest and low level of power, which would classify them as Apathetics. But come drought time? You will have a much higher level of interest for most people and they will shift from the Apathetics to the Defenders. They may not have a high level of power, but their interest in water supply reliability is much higher. Not everyone who is powerful is interested in all issues. For water supply, there are frequently groups that simply do not perceive water supply to be an issue, and choose to focus their energy elsewhere. They would be considered Latents (“latent” means that the interest is lying dormant, but could be expressed with the right circumstances). A Latent stakeholder might become more interested in water supply reliability if he/she were involved in a development that needed water, if there was a drought, or if there were mandatory watering schedules or penalties that affected his/her interests. One of the most important issues in water supply management in the state of California is the challenge of the Sacramento-San Joaquin Bay Delta. Formed by the confluence of the Sacramento and the San Joaquin Rivers, the Bay Delta, south of Sacramento is the source of continual stakeholder challenges. Who are the stakeholders in the Bay Delta? At first, it seems obvious: there are residents and farmers who live and work in the Delta. While they are the most visible stakeholders, the water supply for much of Southern California flows through the Delta so Central Valley farmers and Southern Californians are also stakeholders (most Southern Californians would be Latents though until a crisis arises). Likewise, Northern Californians are stakeholders, because this is water that is leaving their area. Frequently discussions about the Bay Delta are framed around the strong interest and immense amounts of power that Southern California wields and the high interest, but low amounts of power that the farmers in the Bay Delta hold. We will discuss more about the Bay Delta in the section on the State Water Project. You've learned about the importance of involving stakeholders and that stakeholders can be classified as internal or external and in terms of power and influence as well as interest. In Part Two of this text, you'll look at four major surface water development projects in terms of stakeholders. Try It! 1. Identify a water-related issue in your area. Try typing into Google "water issues" and the name of the community. Who are the stakeholders? Classify them as internal or external. Classify each stakeholder on a grid in terms of their interest and power. 2. In the water-related issue you chose above, what are ways (other than the drought) to increase the level of interest of stakeholders in the issue? 3. Add the stakeholders in the conservation program rule change scenario to a chart in terms of interest and power. Who has both a lot of interest and a lot of power? Who has neither interest nor power? Key Terms Stakeholders⁠—People or organizations with a “stake” in an idea or concept

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/01%3A_Water_All_Around_Us/1.04%3A_Stakeholder_Concepts.txt

In Part Two of this text, we’ll explore supply-side management. A supply-side management approach to water concentrates on securing more water supplies through engineering feats. Supply-side management was frequently done by building massive engineering projects to move water hundreds of miles. While they were impressive projects at the time, today, there are more significant regulatory hurdles to building supply-side projects, including environmental regulations. The difficulty of building major infrastructure projects has led to more work being done with exploring alternative supplies and reducing demand. For a long time, human beings have related to nature as if nature was something to be conquered. In the United States, until the 1960s, the natural environment was viewed as mostly inconsequential to expansion and development. The environmental movement, beginning with the publication of Rachel Carson’s Silent Spring in 1962 and continuing with the Cuyahoga River catching on fire due to pollution in 1969, began to change the way we related to nature. Perhaps nature wasn’t something to be vanquished as an enemy. Perhaps nature isn’t limitless. As you examine four large public works projects in California, it is important to keep the shifting mentality of these times in mind. Each project was a feat to build at the time, and in some cases seen as a battle of man against nature. With current regulatory requirements, these projects would be just about impossible to build today. In Part Two, we will cover these topics: • Water Development Projects • Los Angeles Aqueduct • Colorado Aqueduct • Central Valley Project • State Water Project • Alternative Water Sources • Recycled water • Gray water • Stormwater • Desalination Water Development Projects The primary challenge in water supply planning in California is usually framed as spatial. Most of the water is in the northern part of the state and most of the people live in the southern part of the state. In other words, the supply does not exist where the demand is. However, there is an additional challenge as well. Much of California receives water during the winter and early spring when the demands are the least, and not during the summer and fall when the demands are the greatest. This creates a temporal (time) challenge because the supply has to be stored until it is needed. The map below shows the population centers in the Bay Area and Los Angeles Area as well as the volume of storage at various reservoirs throughout California. Notice how storage is concentrated in central and Northern California away from Southern California. This frames many of the water development projects. Thumbnail: The Second Los Angeles Aqueduct Cascades, located in Sylmar. (CC BY-SA 3.0; Los Angeles via Wikipedia) 02: Supply-Side Management Learning Objectives After reading this section, you should be able to: • Identify driving factors in the construction of the Los Angeles Aqueduct • Classify stakeholders in the construction of the Los Angeles Aqueduct • Evaluate the impacts of Decision 1631 Year Population 1850 1,610 1860 4,385 1870 5,728 1880 11,183 1890 50,395 1900 102,479 To understand current day Los Angeles, you need to understand the population explosion in the last two hundred years in the Los Angeles basin. Los Angeles was initially a Spanish pueblo when founded in 1781 and it had a small population. A combination of surface water from the Los Angeles River and groundwater from artesian springs remained sufficient supply for a long time. As you know, Los Angeles was entitled to these supplies of surface water and groundwater because of pueblo water rights. While the supplies were sufficient for the existing population, the introduction of cattle ranching and citrus cultivation in the 1880s coupled with a drought resulted in strained water supplies. Now, imagine you are the superintendent of this water system within California, which has been reliable under current conditions, but is strained by more and more people. Ack! Look at those numbers! You're going to run out of water! In 50 years, the population increased from just over fifteen hundred to over one hundred thousand people. This is the fix William Mulholland found himself in as superintendent of the water system: a burgeoning population and a dwindling water supply. His friend and colleague, former mayor of Los Angeles, Fred Eaton, suggested the Owens River as a potential supply. The Owens River relied on snowmelt from the Sierras. In order to obtain the rights for the water, the land surrounding the river was purchased to obtain water rights. Both Eaton and Mulholland were engineers. They were intrigued by the idea that the water could be conveyed entirely by gravity with a slight slope in the aqueduct from more than 3800 feet above sea level to 1400 feet above sea level. The energy from the water was even enough to generate electricity at a number of power plants that were built along the way. In many ways, their fascination with the engineering aspects of the project may have kept them from fully considering other ethical concerns as they orchestrated purchases of land in the Owens Valley. Year Population 1910 319,198 1920 576,673 1930 1,238,048 1940 1,504,277 1950 1,970,358 1960 2,479,015 1970 2,811,801 1980 2,968,579 1990 3,485,398 2000 3,694,742 2010 3,792,621 Eaton and Mulholland certainly seemed to disregard stakeholders in this potential project. For example, the residents of the Owens Valley, including farmers, ranchers and the indigenous Paiute people, were certainly going to be impacted by directing the water to Southern California. These stakeholders, whose lives were dependent on the water, had very little power to mount a protest at the time. And, in fact, they generally were not asked for permission. The purchases of land in the Owens Valley were conducted in ways that seemed underhanded and non-transparent, including agents for the City of Los Angeles representing themselves as from the Bureau of Reclamation. At the point when actual stakeholders in Southern California were brought in to fund and approve the project, the land was already purchased. This is a classic example of stakeholders not being consulted until the project is almost a fait accompli. Even though Mulholland had found enough water for the existing population in Los Angeles, the population continued to grow. By 1923, Mulholland had explored the possibility of bringing water from the Colorado River as well as the second portion of the Los Angeles Aqueduct to Mono Lake. Both projects moved ahead because it was clear that the original Los Angeles Aqueduct was not enough. And, in the end, even the second addition to the Los Angeles Aqueduct was not enough. The Los Angeles Aqueduct was completed in three parts: • Part One: 1913 - Los Angeles voted 10 to 1 to authorize \$23 million for the first Los Angeles Aqueduct and it is subsequently built. • Part Two: 1940 - Los Angeles votes to extend the Los Angeles Aqueduct to the Mono Lake watershed for \$40 million and the extension is built. • Part Three: 1963 - Los Angeles begins the construction of the second Los Angeles Aqueduct project In sum, using only gravity, the Los Angeles Aqueduct encompasses canals from the Mono Lake watershed to Los Angeles stretching over 340 miles in three separate projects. While the Los Angeles Aqueduct provided a great benefit to the residents in Southern California, it left the Owens Valley a dust bowl, including carcinogenic dust containing cadmium and nickel. After numerous years of protest and litigation, the State Water Resources Control Board in Decision 1631 drastically reduced the amount of water that could be removed from the Owens Valley from 90,000 acre-feet per year (AFY) to 16,000 AFY. How did this happen? This decision applied the public trust doctrine in a new way. The public trust doctrine addresses rights to things that are owned collectively for public use by the government, such as water and air. This interpretation allowed the water in the Owens Valley to be seen as a public resource and not something that could solely benefit Los Angeles. As a water supply, the Los Angeles Aqueduct provides water that is dependent on local hydrology within Owens Valley. Because of the variability and Decision 1631, Los Angeles has been forced to focus on demand reduction, rely more on alternate sources of water, such as those from Metropolitan Water District of Southern California, and remediation of existing groundwater supplies in the San Fernando Groundwater Basin. Misconception Alert! Many people think that all of the water supply in Los Angeles comes from the Owens Valley. As you saw in this section, only 16,000 AFY currently come through the Los Angeles Aqueduct. The rest of the supply is a matter of other imported water, including the Colorado River, as well as groundwater in the San Fernando Groundwater Basin. Try It! 1. What were some of the drawbacks of removing water from the Owens Valley? 2. What were the effects of Decision 1631? 3. What stakeholders were not consulted in the development of the Los Angeles Aqueduct?

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/02%3A_Supply-Side_Management/2.01%3A_Los_Angeles_Aqueduct.txt

California’s Central Valley is known as one of the most productive agricultural regions on earth, but it was not always this way. For a long time, the Central Valley was ranching country. And then it was farming country, but was farmed “dry,” meaning without supplemental irrigation. It wasn’t until the population influx in the 1850s with the gold miners and the development of a pump that there was a drive to make the Central Valley intensively agricultural. After decades of pumping water for irrigation in the Central Valley and a drought from 1928-1934, the Central Valley Project was conceived as a plan to ensure water supply reliability and protect it from floods. Learning Objectives After reading this section, you should be able to: • Identify and critique the purposes of the Central Valley Project • Anticipate the future crises for the Central Valley Project The Central Valley typifies the challenge of California’s water supply. Most of the rainfall occurs in five months, from December to April. There is enough rain to regularly produce flooding in these months. But when the needs of the plants are the greatest for food production (spring and summer), there is little natural rainfall. Pumping supplemental water made the groundwater levels drop significantly in the Central Valley causing subsidence. Diverting river flows for irrigation brought in the salt waters to the Sacramento-San Joaquin Bay Delta, which meant saltier water, sometimes unfit for irrigation, came inland. The state of California authorized the California Central Valley Project Act of 1933 to sell bonds to fund the project. However, due to the Great Depression, the bonds didn’t sell. The federal government took control of the project with the Rivers and Harbors Act of 1935 and the project was finally approved in 1935 for construction by the federal Bureau of Reclamation, which eventually took over operation. The Central Valley Project was authorized with three key elements in its mission: flood control, water for irrigation and power generation. Water quality was added later to the mission as well as recreation and fish and wildlife enhancement. Although the Central Valley Project is the largest of the federal water reclamation projects and includes reservoirs capable of storing 11 million acre-feet of water, it has a fairly simple structure. Water is stored in Shasta Reservoir and Shasta Dam acts as flood control for the Sacramento River. The Trinity River supplements the Sacramento River. The San Joaquin River supplies areas south of the Delta. The Central Valley Project shares some facilities including San Luis Reservoir with the State Water Project. The photo below shows Shasta Dam, which is exclusively used by the Central Valley Project. Misconception Alert! Many people believe that Shasta Lake is part of the State Water Project. As you learned in this section, this is part of the Central Valley Project. The State Water Project has another larger reservoir that stores water in Northern California, Lake Oroville. These reservoirs are typically confused by many people. The Central Valley Project Improvement Act in 1992 allocated water for fishery restoration. This is similar to Decision 1631 in that a water development project was re-evaluated with current environmental norms. The allocation for fishery restoration is 800,00 AFY, which is perceived as enormous by some. This was a considerable change in the mission of the Central Valley Project from water supply reliability, irrigation, and power generation to fish and wildlife enhancement. Try It! 1. Compare and contrast the Los Angeles Aqueduct and Central Valley Project. 2. Investigate potential challenges to the Central Valley Project in the future. Key Terms California Central Valley Project Act of 1933—Authorized by the state of California to sell bonds to fund the Central Valley Project. However, due to the Great Depression, the bonds didn’t sell. Central Valley Project Improvement Act in 1992—Allocated water for fishery restoration in the Central Valley Project Rivers and Harbors Act of 1935—Authorized by the federal government to fund the Central Valley Project in 1935 for construction by the federal Bureau of Reclamation

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/02%3A_Supply-Side_Management/2.02%3A_Central_Valley_Project.txt

Metropolitan Water District was formed in 1928 with the explicit purpose of picking up on where the City of Los Angeles left off with the planning for the use of the Colorado River. The Colorado River Aqueduct was funded by voters three years later in 1931, begun in 1933 and completed in 1935. Water first began to flow in 1939. Even though this time frame is relatively short, the Colorado River Aqueduct was the result of a series of lengthy and heated negotiations, which we will now explore. Collectively the agreements that govern the Colorado River are known as The Law of the River. Learning Objectives After reading this section, you should be able to: • Differentiate among key agreements that are part of The Law of the River • Conjecture as to possible sources of future disagreement The primary tension with all Law of the River negotiations is similar to the tension in California: spatial. The water doesn’t exist where the population centers are. But the geography of the Western United States is much more vast than just California. There are seven states considered to be within the Colorado River Basin: Wyoming, Colorado, Utah, New Mexico, Arizona, Nevada, and California. These are all primary stakeholders in the use of the Colorado River. The upper basin states include Wyoming, Colorado, Utah, and New Mexico. Upper basin states were especially sparse in population and anticipated that they might need the Colorado River water at some point as their populations increased or industries like natural gas extraction grew, but they didn’t have an immediate need for the water. The lower basin states included California, Arizona, and Nevada, most of whom had burgeoning populations. The upper basin states were originally concerned that if the lower basin states constructed dams, including Hoover Dam, and began to use the Colorado River that under the doctrine of prior appropriation, the upper basin states would not be able to use the Colorado River’s water again. The first important agreement in The Law of the River is the Colorado River Compact of 1922, which divided the basin in half. Each basin had the right to use 7.5 MAF of water based on an average flow of the Colorado River of 18 million acre-feet per year, plus a small allocation to Mexico. While most states ratified this agreement, it took Arizona 22 years to ratify it, which is a window into the contentiousness. Arizona was greatly concerned about not receiving enough water eventually and of California taking water that Arizona was entitled to. The second important agreement in The Law of the River was the Boulder Canyon Project Act of 1928. Negotiations for this agreement lasted seven years, and including four bills being introduced and a filibuster. In this agreement, the lower basin was apportioned among the states: • Arizona - 2.8 MAF • California - 4.4 MAF • Nevada - 0.3 MAF The Secretary of the Interior was directed to function as the authority for water use in the lower basin, including the ability to commission studies on feasibility for dams and storage. It is interesting to note how small the apportionment for Nevada is. As a slightly less important agreement in the Law of the River, the California Seven Party Agreement of 1931 is an agreement for division of water among seven entities. The parties included Palo Verde Irrigation District, Yuma Project, Imperial Irrigation District, Coachella Valley Irrigation District, Metropolitan Water District, and the City and County of San Diego. This agreement temporarily settled longstanding disagreements between agricultural and urban users. The third important act in The Law of The River is an international treaty. In the Mexican Water Treaty of 1944, 1.5 MAF of the Colorado River flow were committed to be received in Mexico. While the amount was agreed upon, the quality of the water remained undetermined. Due to agricultural and urban use, the quality of the Colorado River becomes worse the further south the river flows. A desalting plant for removing salt was eventually built in Yuma, Arizona to increase the quality of the water released to Mexico. In the fourth important agreement in The Law of the River, the Upper Colorado River Basin Act of 1948, the upper Colorado River Commission was created and the Upper Basin was apportioned: • Colorado - 51.75% • New Mexico - 11.25% • Utah - 23% • Wyoming - 14% During the negotiations, it was noted that the originally agreed upon amount of 18 million acre-feet of normal flow for the Colorado River might be an overestimation and that agreements would be better done by percent rather than flat allocations of water. The Law of the River is a complicated set of agreements, and the previous pages only covered the major agreements. It should be clear that there will be issues of allocations, water rights, and urban v. agricultural differences for many years to come. Several recent modifications to the Law of the River were made because of droughts. In 2007, interim guidelines for allocating the Colorado River during water shortages through 2026 were signed by the Secretary of the Interior. Water shortages were determined based on the surface elevation of Lake Mead. In 2012, the United States and Mexico signed Minute 319 that addressed how Mexico’s allocation of 1.5 MAF would change in drought conditions also based on the surface elevation of Lake Mead. Try It! 1. What is the difference between the Upper Colorado Basin Act and the Boulder Canyon Project Act? 2. What is a likely source of disagreement in the future? Key Terms Boulder Canyon Project Act of 1928—Apportioned the lower Colorado River basin among three states: • Arizona - 2.8 MAF • California - 4.4 MAF • Nevada - 0.3 MAF Colorado River Compact of 1922—Which divided the basin in half; each basin had the right to use 7.5 MAF of water based on an average flow of the Colorado River of 18 million acre-feet per year, plus a small allocation to Mexico The Law of the River—Collectively the laws and regulations that govern the Colorado River Mexican Water Treaty of 1944—Committed 1.5 MAF of the Colorado River flow to Mexico; did not describe the quality of water, just quantity Minute 319—An international agreement between the United States and Mexico regarding the Colorado River that addressed how Mexico’s allocation of 1.5 MAF would change in drought conditions also based on the surface elevation of Lake Mead Upper Colorado River Basin Act of 1948—Apportioned the Upper Colorado River Basin by percent: • Colorado - 51.75% • New Mexico - 11.25% • Utah - 23% • Wyoming - 14%

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/02%3A_Supply-Side_Management/2.03%3A_Colorado_River_Aqueduct.txt

The last major water infrastructure project undertaken for water supply in California was the State Water Project (SWP) and it still isn’t quite finished! The SWP major features were outlined in 1957 in the California Water Plan and it was funded by the Burns-Porter Act in 1960 in \$1.75 Billion in general obligation bonds. Learning Objectives After reading this section, you should be able to: • Identify the major stakeholder groups and their needs • Analyze major threats to the Sacramento-San Joaquin Delta in terms of water supply • Project future impacts to the State Water Project The State Water Project is a massive infrastructure project that involves several major stakeholder groups throughout the state of California, all of which have been stakeholders in other water development projects that you’ve learned about: • Northern California communities that wanted flood control protection (as a result of devastating floods on the Feather River in 1955) • San Joaquin-Sacramento River Delta communities that wanted flood protection, but also access to high-quality water for farming • San Joaquin farmers who wanted access to water for expansion of agriculture, but also because of groundwater overdraft issues • Southern California residents who wanted water for future growth and for water supply reliability The State Water Project brought together these stakeholder groups with a combined mission of providing water supply to the San Joaquin Valley farmers as well as Southern California. The State Water Contract was among 32 public water agencies all over the state, including some agencies that formed specifically to contract for SWP water supplies. The terms of the contract were 75 years minimum or until the bonds were repaid. The State of California was obligated to make reasonable efforts to complete the project. The Contractors were obligated to pay even if the water supplies were reduced or the project was not complete. As you might guess, these aren’t great contract terms (paying for a project that is incomplete or reduced in some way). The State Water Project had several purposes: flood control (specifically at Lake Oroville), recreation (e.g., Pyramid Lake, Castaic Lake) and water supply (including primary reservoirs at Oroville and San Luis and terminal reservoirs at Pyramid and Castaic Lake, Lake Perris and Lake De Val). Facilities to convey water through the Delta and for additional storage were not completed. The Delta The Sacramento-San Joaquin Delta (sometimes referred to only as “the Bay-Delta" or “the Delta”) is one of the most interesting places in California to study in terms of stakeholders, science, and water supply. In terms of stakeholders, the Delta is home to historic towns and family farms. Many farms are under sea level with manmade levees their only protection. The Delta is also fully used for recreation—boating, fishing, sightseeing, bird watching (and duck hunting). There are also millions of stakeholders south of the Delta that rely on the water supply that passes through the Delta. So combine various stakeholders with a location that is literally described as the “heart” of the water supply and you can see how there might be inherent conflicts. The Delta has been altered by farmers over the past 150 years and it has also been altered by the operation of the State Water Project and Central Valley Project. It is currently threatened by three primary issues: Seismic—A large earthquake could break down the manmade levee system, allowing seawater into the Delta, and essentially making the water supply undrinkable for anyone south of the Delta Subsidence—Land within the Delta is made of peat soil, which is excellent for farming, but compacts and subsides over time, leading to levees sinking and needing to be repaired and strengthened Sea Level Rise—Sea level rise also threatens the Delta as there is often only a few feet between the top of the water and the top of the levee The most likely path forward is two twin tunnels under the Delta. This is known as the California Water Fix (formerly known as the Bay Delta Conservation Plan). Try It! 1. Identify three purposes of the State Water Project. 2. Write a letter advocating a plan to fix the Delta. Key Terms Burns-Porter Act—Funded the State Water Project in 1.75 billion in general obligation bonds in 1960 This table summarizes the four major infrastructure projects covered. Los Angeles Aqueduct Central Valley Project Colorado River Aqueduct State Water Project Purpose Water supply reliability Flood control Water for irrigation Power Water supply Water supply Flood control Irrigation for farms Stakeholders Southern California residents Owens Valley ranchers, farmers, Paiute tribe San Joaquin Valley farmers Wyoming, Colorado, Utah, New Mexico, Nevada, Arizona, California Southern California residents San Joaquin Valley farmers Northern California communities with flood protection needs Legislation California Central Valley Project Act of 1933 Rivers and Harbors Act of 1935 Central Valley Project Improvement Act in 1992 All under The Law of The River: Colorado River compact of 1922 Boulder Canyon Project Act of 1948 Mexican Water Treaty of 1944 Upper Colorado River Basin Act of 1948 Minute 319 California Water Plan Burns-Porter Act Major Features Owens Lake Mono Lake Lake Shasta San Luis Reservoir Lake Powell Lake Mead Lake Oroville San Luis Reservoir

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/02%3A_Supply-Side_Management/2.04%3A_State_Water_Project.txt

Alternative Water Supplies are supplies other than groundwater and surface water. Frequently, they are “reused” supplies, meaning they were potable water supplies that were captured for use individually or system-wide after being used once. Here are a few quick definitions to begin: Recycled Water Gray water Storm water Desalinated Water Heavily treated wastewater that is used for irrigation, groundwater replenishment and as a subsurface barrier against seawater intrusion; typically in California, recycled water is used for irrigation Household wastewater, including water from the washing machine, shower, bathroom sinks, that is captured and reused, but excluding blackwater, which is water from toilets and kitchen sinks; commonly referred to as "lightly used" water Runoff from precipitation (rain or snowmelt) that flows overland; may mobilize pollutants and is better to capture on site to replenish groundwater Ocean or brackish water that has had the salt removed to make it potable; two primary methods are used worldwide, but in the United States, reverse osmosis is most frequently used Learning Objectives After reading this section, you should be able to: • Analyze the water supply portfolio for several geographic locales in terms of the likelihood of adding an alternative water supply • Differentiate among types of alternative supplies and their appropriateness, given different situations Recycled Water You may hear “recycled water” used in a variety of ways in the United States and abroad. In California, specifically, there is some confusion in terminology. Changes to a variety of codes occurred in 1995 when “recycled water” became the term of choice rather than “reclaimed water.” These are essentially the same thing. Regulations for the level of treatment for various uses are in Title 22 of the California Code of Regulations. What happens to wastewater when it leaves your house? It travels through a series of larger and larger pipes to a wastewater treatment facility. Alternatively, if you live rurally, your wastewater may be held and separated in a septic tank on your own property. Wastewater that has undergone primary treatment has had the solids removed. Wastewater that has undergone secondary treatment has had organic materials removed through biological processes. Secondary treated wastewater can be used for groundwater recharge and irrigation. Water that has undergone tertiary treatment has undergone sedimentation, chemical flocculation, and filtration. As you might imagine, water that has undergone tertiary treatment has a range of uses, even those involving body contact, such as recreational use in lakes, as well as irrigation. Recycled water has only system-wide applications in that individual homes are not creating and using recycled water. You may be familiar with recycled water for irrigation of golf courses, medians, but it also can be used for groundwater recharge, including to act as a seawater intrusion barrier. Orange County Water District treats recycled water in a three-step process of microfiltration, reverse osmosis, and ultraviolet treatment. The treated water is then injected into the groundwater basin. The water serves as a barrier against the intrusion of ocean water into the aquifer. Recycled water seems like an important source to add to a water supply portfolio. After all, what community in California wouldn't want a reliable source of water for irrigation of landscapes? And what coastal community wouldn't want water to inject into the ground as a barrier of seawater intrusion. Overall, recycled water can decrease the demand for potable water by providing an addition to a water supply portfolio. But recycled water is expensive. Next to desalination, it is one of the most expensive options out there (think of the treatment costs!). Like many aspects of infrastructure, recycled water is politically appealing to residents, but the added costs are not. Gray water Certainly, the water that you drink, wash your clothes in, and use to bathe needs to be potable. But what about the water that you flush your toilets with? What about the water that you irrigate with? The premise of gray water use is that not all water that we use on a daily basis needs to be potable. Keeping this in mind, you then have to consider what can be reused in your indoor water use. Wastewater from toilets and wastewater from the kitchen sink both contain bacteria from feces or meats. But wastewater from a washing machine can be reused without many concerns, assuming diapers are not washed or clothes are not highly soiled, greasy or contaminated. The easiest gray water system to construct is called “Laundry to Landscape.” Wastewater from the washing machine is directed to a drip irrigation system outside the house. Water isn’t stored in any fashion - when you run a load of clothes in the wash, you are irrigating with the wastewater directly afterwards. You can see that you would need to time your laundry - washing everything on Sunday would lead to too much water for irrigation. Doing a load of wash every other day might be enough water for irrigation in the summer. What do you need in order to have a simple Laundry to Landscape system? • Your washing machine should be located close to an exterior wall in order to run a pipe to the outside of the house • Your house should be slightly above the area that you are irrigating so you can use gravity to direct the water to the drip system and the plants without a pump (though pumps that remove water from washing machines can be powerful and enough to move water some distance); • You need to have plants that can be irrigated with drip irrigation (shrubs or trees); and • You need to install a diverter valve at the washing machine that would allow especially dirty loads of laundry to drain toward the sewer or septic tank and not into your irrigation system. There are more complicated gray water systems that involve storing gray water in tanks and using pumps and filters, but most gray water practitioners agree that simple is best. Here are some best practices in residential gray water systems: • Don’t store gray water • Minimize body contact with gray water • Allow gray water to infiltrate the soil with drip irrigation, not pool on the surface • Simple is better. Avoid pumps and filters. • Install a diverter valve • Match needs of plants Please note that these are best practices, but not necessarily rules and regulations. Rules and regulations vary by city and county. In a recent study of graywater systems in the Bay Area, it was noted that the most common problem in gray water systems was clogs, but this wasn't much of a surprise because most people reported performing no maintenance on the system. Plants were generally just as healthy as with a standard irrigation system and some were overwatered and some were under watered. Overall, people saw an average reduction in water use of 26%. There was at least one unintended consequence - with an abundance of water to irrigate, some people planted more plants and their irrigated area increased in size. There are a number of institutional hurdles to expanding gray water use. The primary hurdle is one related to the construction of homes: homes are plumbed with intermingled graywater and blackwater. This means that the wastewater from the entire home is treated as blackwater and sent to the sewer or septic tank. Additionally, if you check the city, county and state code related to graywater, they are frequently contradictory. California code, Title 24, Part 6, Chapter 16 a, Part 1 establishes minimum requirements for gray water regulations. Additionally, AB 849 (Gatto) prohibits local jurisdictions from banning gray water. However, a city or county may impose additional regulations so that it becomes too complicated to establish gray water in the home. Furthermore, as you can imagine, setting up a gray water system relies on a knowledge base of basic plumbing and wastewater. It is probably not an overstatement to say that most customers try not to think about this. Misconception Alert! Many people use “graywater” to refer to all sorts of alternative supplies, including recycled water and stormwater. This is simply incorrect, but a common misuse of language. Graywater must be water from indoor use that can be reused, typically for irrigation. It is not wastewater or stormwater. Stormwater Picture the last rain storm that you remember in Southern California. Was there gentle rain for a long time? Or was there a short burst of rainfall? When there is an entire day (or even just an afternoon) of gentle rain, the rain is usually able to infiltrate into the ground, and eventually recharge the aquifers beneath the surface. But much of the rainfall that we receive in California is in bursts with heavy downpours and then days, weeks, and even years of nothing. This type of heavy rain results in a lot of run off. Stormwater is run off that can be captured. Stormwater becomes a problem when it encounters a lot of impervious surfaces, such as asphalt and concrete. These surfaces may hold visible pollutants (e.g., trash, dog poop) and invisible residues (e.g., pesticides, herbicides). When stormwater encounters impervious surfaces and pollutants, it turns can drain pollutants into storm drains and eventually the ocean. What slows down stormwater? Vegetation and pervious surfaces. These sorts of textured surfaces allow water to infiltrate the soil. Parkways, the area in between the sidewalk and the street, can slow water from running off properties and into the street. Planter beds near downspouts can let water percolate rather than run into the street. Plants, whether shrubs, or groundcover, or even trees, can slow water down on slopes and hillsides. What about rain barrels? Aren't they a good way to capture stormwater? Rain barrels are typically used on a residential site to capture water that comes off the roof through the rain gutters. In many parts of the country, rain barrels work well because the water needs of the plant correspond to the times when there are heavy rains. In much of California, the rainfall occurs in the cooler times of the year when the plant water needs are minimal. This means that water in a rain barrel must be stored for lengthy periods of time. And this is where we run into issues with creating the perfect habitat to breed mosquitoes - it’s still water available for irrigation, but it may be there for more than 4-7 days, which is all mosquitoes need to breed. There are other (and better) ways to capture rainfall. On a small scale keeping vegetation on hillsides and parkways, directing downspouts to planter beds, and keeping lots of green plants will decrease stormwater run-off. On a larger scale, stormwater can be captured within a neighborhood. Several neighborhoods within Los Angeles are tackling this. Elmer Avenue in Los Angeles has a stormwater capture area. Catch basins with soft bottoms allow water to percolate into the groundwater rather than re-enter the stormwater system and get flushed into the ocean. There are also bioswales in the yards near the catch basin to slow the water and allow it to infiltrate rather than run off. Desalination You may hear desalination or “desal” frequently touted as the solution to all water supply problems. You may wonder why there are not more desalination plants around if it is such the perfect solution. Good question—read on. There are two primary methods of desalination: thermal and membrane. In thermal desalination, water is heated in a boiling chamber, it then condenses in a dome, and collects in a chamber leaving all the salt behind. In membrane desalination, seawater is screened, filtered, and pushed through a reverse osmosis membrane under high pressure, and then the distilled water is treated to drinking water standards. These methodologies aren’t that complicated, but they do tend to use large amounts of energy, leading to a high cost. For both methods of desalination, there are similar hurdles: Seawater intake—Seawater needs to be removed from the ocean very carefully so as not to hurt plant and animal life. Typically, a speed slower than the ocean current is best. Power consumption—Typically, the reverse osmosis process uses the most energy, which contributes to the highest costs Brine—While brine can be returned to the ocean, most plants and animals thrive in a small range of salinities. There may be environmental consequences associated with creating areas of higher than normal salinity. Santa Barbara, California, provides an interesting case study in desalination work. As a result of the drought in the 1980s, the City of Santa Barbara along with Montecito and Goleta constructed a desalination facility with a capacity of 7,500 acre-feet per year (AFY) with expansion to 10,000 AFY. Construction costs of \$34 million were shared based on proportions of water provided for the City of Santa Barbara of 3,181 AFY, Montecito of 1,250 AFY and Goleta of 3,069 AFY. By the time the desalination facility was built, the drought had ended and a period of heavy rainfall had begun. The plant operated for March, April, May and June of 1992 during and after a time of heavy rainfall. Then the desalination plant was put on standby. After it was paid off over 5 years, Goleta and Montecito decided not to renew the contract and subtracted desalination from their water supply portfolio. Santa Barbara has recently decided to re-activate the desalination plant as the sole funder of this enterprise. The facility will produce 3,125 acre-feet per year or roughly 30% of Santa Barbara's water supply in a year. In terms of hurdles, the intake is 2,500 feet off shore with openings of 1 millimeter and takes in water at a rate of 0.5 feet per second, which is slower than the existing current. Additionally, the power consumption for reverse osmosis has decreased by 40% since the facility was designed. The brine has twice the salinity of seawater and will be discharged at an outfall shared with the wastewater treatment facility. A study was recently completed with Scripps Institute of Oceanography, which suggested the city can comply with discharge requirements. It probably goes without saying, but let's say it anyway: desalination is more appropriate for coastal communities, such as Santa Barbara, San Diego or Santa Cruz. For an inland community to fund desalination, the inland community would also be evaluating an expensive pipeline to transport water or negotiating a water exchange with a coastal community in order to avoid building the pipeline. Proximity to the source is everything in desalination. Alternative Supply What is it? What are the benefits? What are the drawbacks? System-wide Opportunities? Desalinated water Potable water that was ocean or brackish water that has the salt removed to make it potable A drought-proof supply Generally, the most expensive source of supply. Disposal of the brine can be problematic. High energy use. Yes Gray water Non-potable household wastewater, including water from the washing machine, shower, bathroom sinks, that is held and reused; excludes blackwater, which is water from toilets and kitchen sinks Cost-effective method for residential irrigation Supply and demand must be balanced. Easy to end up with too much supply Water can contain pathogens. No Recycled water Non-potable water that is treated wastewater that is used for irrigation, groundwater replenishment and as a barrier against seawater intrusion Non-potable use of water; can recharge groundwater Expensive; requires separate plumbing system of purple pipes Yes Stormwater Non-potable water that is runoff from precipitation (rain or snowmelt) that flows overland; may mobilize pollutants Can recharge groundwater Must be captured, retained and allowed to percolate Yes Try It! 1. A coastal community in Southern California is considering diversifying its water supply with an alternative water supply. Which type of water supply is considered “drought-proof”? Why? 2. An inland community is looking for an alternative supply to use for recharge. Which type of supplies make sense to use for recharge? Why? Key Terms Desalinated water—Potable water that was ocean or brackish water that has the salt removed to make it potable; considered a drought-proof supply Gray water—Non-potable household wastewater, including water from the washing machine, shower, bathroom sinks, that is held and reused; excludes blackwater, which is water from toilets and kitchen sinks Recycled—Non-potable water that is treated wastewater that is used for irrigation, groundwater replenishment and as a barrier against seawater intrusion Stormwater—Non-potable water that is runoff from precipitation (rain or snowmelt) that flows overland; may mobilize pollutants

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/02%3A_Supply-Side_Management/2.05%3A_Alternative_Water_Supplies.txt

In Part Three, you will shift from supply-side to demand-side management. When we manage the water demand, which is to say the water “need” or water “consumption” you tend to lessen the need for supply-side management. That is to say, if you can get people to need less water, you do not need to go out and find more water for them to use. In Part Three, we will cover: • Regulations that affect conservation in California • Water loss • Water rates • Indoor water use and conservation • Outside water use and conservation • CII water use and conservation • Social marketing campaigns Everything listed above addresses ways of decreasing demand for water, whether it is a regulation that mandates watering schedules, an aggressive leak detection program run by a water district, higher water rates for higher consumption, or toilet rebates. There are many ways to control the demand for water. One of the most effective ways is with regulation. This frequently isn’t what people expect to or want to hear, but between statewide legislation, statewide mandates from the Water Resources Control Board, and California Building Code requirements, demand was substantially regulated during the drought in California. In this section, you will: • Analyze potential outcomes of the requirements of SBX7-7 • Identify the prohibited measures by the State Water Resources Control Board • Interpret requirements of building codes in California for water conservation • 3.1: Regulations • 3.2: Water Loss If you were asked to picture water loss, you would probably think of a leak. Water is definitely lost through leaks. In this section, you will learn about types of leaks, but there are other ways systems lose water as well. As a general rule, you can estimate the amount of loss in a system by subtracting total consumption from total production. • 3.3: Water Rates Retail water suppliers generally include both a fixed and variable (volumetric) charge on a water bill. The fixed charge is the same for each month regardless of the water consumption because it is based on the size of the pipe coming in and the costs that remain the same for the water agency; the variable rate is volumetric and based on consumption (water use). • 3.4: Indoor Water Use When you start to talk to people about conservation, they generally want to discuss ways of reducing their indoor water consumption, particularly bathing less. This is a problem - most of the water in the residential sector in California is used outside! And, frankly, no one in conservation wants to decrease basic hygiene of the general public. Still, indoor water use and conservation is not a bad place to start because it is a place people are very familiar with. • 3.5: Outdoor Water Use How much water is used outdoors? Most estimates for outdoor water use in the United States suggest that it is more than 50% of all water used for residential use. In general, the hotter the locale, the more water is used for landscaping. • 3.6: CII Water Use What do a car mechanic and an aerospace engineer have in common? They both work in the Commercial, Industrial, and Institutional (CII) section, which is very diverse in terms of water use. Using water for cleaning as a car mechanic or water for manufacture of aerospace parts are very different uses. As we study CII customers, you’ll be able to bring together what you’ve learned about indoor and outdoor conservation and apply it to the workplace. • 3.7: Social Marketing Campaigns As you have seen, there are major water infrastructure projects that can be relied on to a certain extent to bring water to the thirsty parts of California. But how can you decrease the amount of water that is needed in the first place? This is called managing demand. You’ve learned a variety of tools from regulation to restrict water use or limit waste, to building codes that require more efficient devices to water loss detection to conservation programs. Thumbnail: The spillway at Monticello Dam, Lake Berryessa. (Public Domain; Jeremybrooks via Wikipedia) 03: Demand-Side Management SBX7-7 For many years, water agencies conducted water conservation programs as public outreach. They often set goals of fairly minimal savings over long periods of time—in other words, goals that were easy to achieve. Rebates were intended to help people save water, but also make them feel good and appreciate the water agency at the same time. Meanwhile, water agencies often had their own revenues in mind. They did not want people to be wasteful with water, but they also calculated a certain demand in order to set rates. They did not want too much conservation without planning for a reduction in revenue. SBX7-7 changed everything. In 2009, Governor Schwarzenegger signed into law SBX7-7, the Water Conservation Act of 2009, which required retail water suppliers to determine their baseline per capita water use and reduce water use by 20% of their baseline by 2020. What happens if a retail water supplier misses its target? Compliance with SBX7-7 determines eligibility for state water grants and loans. Failure to meet the target establishes a violation of law for administrative or judicial proceedings. This means a supplier wouldn’t be eligible for many grants and loans that suppliers rely on to fund infrastructure, and could have legal actions taken against it. No doubt in 2020 some water suppliers will not meet SBX7-7 goals either intentionally or unintentionally. What will actually happen to them? Sometimes it is worth making a distinction between agencies that are making an effort and those that are deliberately ignoring the law. Some may be penalized with proceedings and some may not be because they made a good faith effort. This will be interesting to see. State Water Resources Control Board Mandatory Measures While SBX7-7 set a long-term goal of 20% by 2020, in July of 2014, mandatory measures from the State Water Resources Control Board (SWRCB) were enacted to combat the severity of the drought. The table below walks you through the executive and regulatory decisions about the drought. January 2014 Governor Brown declared a drought state of emergency. April 2014 Governor Brown signed an Executive Order (April 2014 Proclamation), which asked for reductions of 20% by all Californians with an emphasis on outdoor conservation. The order prohibited HOAs from punishing homeowners who limit their watering, July 2014 State Water Resource Control Board (SWRCB) asked for mandatory reductions with an emphasis on outdoor reductions. March 2015 SWRCB adopted an expanded mandatory emergency conservation regulation, which prohibited: • Non-recirculating fountains • Hosing sidewalks and driveways to clean • Washing a car without a shut-off nozzle • Run-off from over-irrigating Water suppliers are tasked with enforcement and ordered to report data monthly to the SWRCB. April 2015 Governor Brown directed the SWRCB to implement mandatory water reductions in urban areas to reduce urban use overall by 25% compared to 2013. Instructions to the SWRCB included considering relative per capita water usage of each supplier’s service area and requiring areas with higher use to cut consumption more. May 2015 SWRCB adopted an emergency conservation regulation with residential gallons per capita per day (R-GPCD targets). January 2016 Mandatory measures are extended through October 2016 with adjustments to R-GPCD possible for suppliers for climate and growth. May 2016 Prohibited measures described above become permanent. Water suppliers are allowed to “self-certify” their conservation targets by analyzing their water demand (average of 2013 and 2014) and their water supply and using a target for any shortfall. So while SBX7-7 concentrated on long-term conservation goals compared to a baseline of total water production, the SWRCB mandatory measures concentrated on short-term conservation goals, particularly in the residential sector and particularly outdoors. The goals (or targets) were widely criticized for not being fair. This is usually referred to as having "equity issues." While the SWRCB separated out commercial, industrial and institutional water use and concentrated strictly on a residential water reduction, it tended to penalize the water suppliers with higher per capita consumption with larger goals. Water suppliers with higher per capita consumption tended to be inland areas with higher water demand—meaning it was simply hotter inland and the plant water needs were much greater. And then the winter of 2017 was wet. In Northern California, it was unbelievably wet breaking records. In Southern California, it was slightly wetter than average. In the Santa Clarita Valley, while it "felt" like a break from the drought, you can see that Water Year 16/17 (October 2016 – September 2017) was only slightly wetter than average with around 20 inches of rain for the entire year. Is the drought over? Certainly, if you rely on imported water from the State Water Project, there was plenty of water in 2017. But most Southern California communities that used groundwater still found their groundwater supplies below average. For some parts of Southern California, including Ventura and Santa Barbara Counties, the drought was definitely not over. Looking at the graph above, would you say the drought was over in the Santa Clarita Valley? As of this writing, the State Water Resources Control Board is implementing targets by service area to include an indoor component, a landscape component, a water loss requirement, and separate measures for commercial, industrial, and institutional users. Building Codes What type of regulations govern the building of a home? In terms of water use, how does a developer decide what type of toilet to use? Or aerators to install? Or landscaping to put in? These sorts of choices are governed by layers of codes, including city, county, state, and federal. In most instances, when there are overlapping standards, the most stringent apply. Cal Green Building Code (2014 update) Indoors Water Use Toilets 1.28 gallons per flush Showerheads 2.0 gallons per minute at 80 psi Bathroom faucets 1.2 gallons at 60 psi Kitchen faucets 1.8 gallons at 60 psi Outdoor Controllers All controllers shall be weather-based or soil-moisture-based and shall have a rain shut off All of the indoor devices listed above have a specific flow or flush rate. This is the rate from the manufacturer and may not be the rate in real life. Toilets, for example, leak over time and may use more than 1.28 gallons per flush. Similarly, faucets have a rating at 60 pounds per square inch, but it is entirely possible to have more pressure inside a house and use more water because of it. Building codes are very useful in driving long-term demand downwards, primarily inside the home. In California; if there was a change to the code that forbid turf grass from being installed in new homes, demand could be driven down further outside rather than simply relying on controllers. The graph above shows the savings in 2020 in the Santa Clarita Valley as a result of various measures, including incentives (rebates), plumbing code and standards, pricing and water loss reduction. Note that 9% of the savings are from conservation pricing and 25% of the savings are from plumbing codes and standards. These are powerful ways to drive demand down. Try It! Conduct a quick inventory of a bathroom at home. What can you tell about the flow rate of these devices? Toilets ___________ gallons per flush Showerheads ___________ gallons per minute at 80 psi Bathroom faucets ___________ gallons at 60 psi 1. Which type of regulation (SBX7-7, SWRCB restrictions, or Building Code) do you think will result in the most savings over time? 2. Which measure prohibited by the SWRCB would be the most difficult for customers to prevent?

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/03%3A_Demand-Side_Management/3.01%3A_Regulations.txt

Learning Objectives After reading this section, you will • Differentiate among real losses • Differentiate among apparent losses • Prioritize leak fixing If you were asked to picture water loss, you would probably think of a leak. Water is definitely lost through leaks. In this section, you will learn about types of leaks, but there are other ways systems lose water as well. As a general rule, you can estimate the amount of loss in a system by subtracting total consumption from total production. Real losses include leaking pipes, joints, fittings; leaks from reservoirs and tanks; reservoir overflows, and improperly open drains and system blow-offs. Real losses are typically used (in terms of a percent of total production) to show how efficient a water retailer is in managing its assets. You can think of real losses as three primary types: Reported leaks - These are the most dramatic leaks that end up in the local newspaper. These have high flow rates, but a relatively short run time because they are reported. They can be disruptive to staff (Stop everything and fix this!) as well as the customer (Why don’t I have any water?) Unreported leaks—These are hidden underground. They may have low to moderate flow rates, and often very long run times. How would a utility find these leaks? They would need an active leak detection program of some sort or the leak would need to increase in flow to become noticed on the surface. Background leakage—All systems have weeps and seeps. The flow rates are generally too small to be detected and not cost-effective to be fixed (until the leak escalates). Keep in mind that as much as customers like to have water under relatively high pressure delivered to their homes, and high pressure is necessary to make it up to the top of hills in your service area, high-pressure systems are much more likely to leak than lower pressure systems. Leaks are wasted water and money, but there are other consequences too. Wet areas may be liabilities for a water supplier and create a slippery surface or even a sink hole where people may get hurt. Misconception Alert! Many people think of real losses as the only type of loss. But there are losses that occur in all sorts of ways, which you’ll learn about below. Imagine what has to happen from the meter read to the actual delivery of the bill. Inaccuracies can be introduced in any number of ways. Real losses are not the only source of leaks; they are just the most obvious ones. Water can be lost because of under-recording customer meters or theft. These are considered apparent losses. With an apparent loss, water may not be actually lost from the system. You can think of apparent losses as stemming from these sources: • Customer metering inaccuracies—It is considered a best practice for all connections to be metered (though in some communities this is certainly not the case). Metering allows customers to make a connection between the volume of water used and the cost of water. It also provides information for water resource planners in terms of consumption trends. As meters age, they slow down. Without a meter replacement program, a water utility could easily be under billing based on customer metering inaccuracies. • Customer billing system errors and data handling errors—Think of the process to get information from the customer meter to the customer water bill—there are a number of steps, including the actual read of the meter and transfer of information into the customer information system to billing. At any point in data transfer, an error can occur, but data errors can also be introduced in the analysis if estimates are used or accounts are closed or not transferred between customers. • Unauthorized consumption—You would be surprised how much water is stolen! Yes, intentionally stolen! This could be an illegal opening of a fire hydrant, illegal connection, or tampering with a meter. Some customers will reactivate their own service connection after the service connection has been terminated for non-payment. As you can see, there are a half dozen ways a water utility can lose water. The biggest reason for recovering water that was lost through real and apparent losses is revenue. This is literally money that is lost, whether it is by a medium-sized leak underground, a broken main above ground, theft, or meter reading errors. Other than weeps and seeps, all of these losses can be fixed, and usually cost-effectively. Try It! 1. If a water agency tracks the difference between consumption (the sum of all meter reads) and production (the sum of all water pumped from the ground or imported), would the difference between consumption and production be real or apparent losses? 2. What is the relationship between pressure and leaks? 3. What might be an argument to implement a leak detection program? Glossary • Apparent losses—Losses from customer metering inaccuracies, customer billing system errors and inaccuracies, and unauthorized consumption (theft) • Background leakage—Weeps and seeps that have small flow rates and are not cost-effective to fix • Real losses—Leaking pipes, joints, fittings; leaks from reservoirs and tanks; reservoir overflows and improperly open drains and system blow offs • Reported leaks—Leaks that are reported with high flow rates, but short run times • Unreported leaks—Leaks that are most likely hidden underground with moderate flow rates and long run times

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/03%3A_Demand-Side_Management/3.02%3A_Water_Loss.txt

Learning Objectives • In this section, you will: • Differentiate among types of water rates • Classify rates according to whether they encourage conservation You can look at the ways that water suppliers can organize a volumetric rate structure: Type of Rate Description Benefits Drawbacks Uniform Rate a constant unit price for all volumetric water sales Simple and perceived as equitable; easy to implement (not a lot of math!); some revenue stability Not much of a conservation signal Declining Block Rates the unit price for each block of water use is charged at a lower unit rate than the previous block High-water users benefit from lower rates than in other structures Perceptions of inequity, does not encourage conservation; complicated to design Increasing Block Rates the unit price for each block of water use is charged at a higher unit rate than the previous block Encourages conservation Perceptions of inequity; complicated to design Seasonal Rates the unit price varies by time period (generally a higher price during peak demand months) Encourages conservation Complicated to design and administer The common wisdom is to encourage conservation, you need to make people aware of how much water they use, and increase the price as they use more. In this way, customers get a price signal to be conscious of their water use and are intentional about their water use and conserving. You can see in the chart above, two rate types (uniform and declining block rates) do not encourage conservation. They actually could encourage an increase in demand. Why do these rate types exist? A uniform rate exists for one reason: equity (or perceptions of equity). A uniform rate treats the smallest customer and the largest customer exactly the same with the same volumetric rate. A declining block rate exists when the agency wants to increase water use, presumably by commercial and industrial users who would benefit. Why not increase rates across the board to increase conservation? Rates are considered governed by Proposition 218 and have to go through a public process that ties the rates to actual costs from the water retailer. In general, Proposition 218 is intended to make sure that additional taxes are brought to the public for a vote. In short, a water retailer cannot charge more than proportional costs of the water per parcel served. This means that the water retailer can’t charge high fees just because it wants to decrease consumption overall. In the case of Capistrano Taxpayers Association v. City of San Juan Capistrano, the trial court decided that the City of San Juan Capistrano had not provided enough justification for their costs for the higher tiers. This has been interpreted by some as making tiered rates illegal, but this isn’t really the case. Rate calculations need to be able to be justified by the cost of service. If it is costing a significant amount more to purchase an additional source of expensive supply because of high water users, these costs can be passed on to the high water users. But you can’t simply charge high water users more because you want to decrease their consumption. Misconception Alert! Many people disregard the fixed charge on their bills and focus on the volumetric charges. While the volumetric charges are a measure of how much water is used, they may not actually be the bulk of the cost. Much of the cost may be in the fixed charge. There is just very little you can do about the fixed charge. Try It! 1. Check out your water bill. How are you billed? Is there a fixed and volumetric rate? What type of rate is the volumetric rate? 2. What types of rates will encourage conservation? Why? Glossary • Declining block rates—The unit price for each block of water is charged at a lower unit rate than the previous block • Increasing block rates—The unit price for each block for water use is charged at a higher unit rate than the previous block • Proposition 218—The legislation that governs the public process for rate setting. In general, Proposition 218 is intended to make sure that additional taxes are brought to the public for a vote. • Seasonal rates—The unit price varies by time period, generally with a higher price during peak demand months • Uniform rates—A constant unit price for all volumetric water sales

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/03%3A_Demand-Side_Management/3.03%3A_Water_Rates.txt

Learning Objectives In this section, you will: • Analyze indoor water consumption • Audit and track your own indoor water use When you start to talk to people about conservation, they generally want to discuss ways of reducing their indoor water consumption, particularly bathing less. This is a problem - most of the water in the residential sector in California is used outside! And, frankly, no one in conservation wants to decrease basic hygiene of the general public. Still, indoor water use and conservation is not a bad place to start because it is a place people are very familiar with. In the graph below, based on real data from residential homes, you can see that toilets are the biggest users of water in the home, followed by showers and faucets, and then clothes washers. Surprisingly, 14% of all water metered to the home is also lost to leaks. That puts an interesting spin letting a leaky faucet drip. It’s using only a little less water than your faucets! Let’s return to our inventory of your bathroom fixtures. What did you discover when you inventoried your bathroom? Toilets _____ gallons per flush Showerheads _____ gallons per minute at 80 psi Bathroom faucets _____ gallons at 60 psi Toilets How many gallons does your toilet use? Sometimes it is difficult to tell how many gallons per flush a toilet has by observation. But if you remove the tank lid, often the number of gallons per flush is stamped somewhere on the inside of the tank at the top. In some toilets, you can also find the gallons per flush on the flat surface behind the seat lid. And, of course, in a store, the gallons per flush is written on the box. If you are browsing in a store, a toilet with the WaterSense label guarantees that the product is 1.28 gallons per flush. In the United States (as of 2017), you can purchase 1.6 gallon per flush toilets in most states, which is the federal standard, but in California, you can only purchase 1.28 gallon per flush toilets. This is 20% less water used per flush. (1.28 compared to 1.6). Yuck! you may say. That’s not enough water. Actually, it’s plenty. Some of us remember the early 1990s, which was the time “low-flush” (a.k.a. low-flow) toilets came on the market in California. These were the first toilets that used 1.6 gallons per flush. Unfortunately, most of them were not re-engineered from the 3.5 gallon per flush toilets of the previous generation. A 1.6 gallon per flush toilet was pretty much a 3.5 gallon per flush toilet with less water. And these did not work well. Water agencies up and down the state of California had to deal with angry customers who felt that the water agency rebate had “recommended” a toilet with poor performance. No one wants a repeat of this. The current 1.28 gallon and 1.6 gallon per flush toilets work well. To check the performance rating of your toilet, see map-testing.com for an entire database of toilet rankings. Toilet-Related Conservation Toilet rebates are a “classic” conservation program and a favorite of many in conservation. Why? The toilet stays in place for a long time. The savings are essentially “hard-wired” into the home. In this type of rebate program, a customer buys an approved product from a list, and the water agency gives a check or a credit on the bill after the purchase of the toilet. In order to receive the credit or check, the customer must present the receipt and purchase from the list. The approved list is important. It is a best practice to only rebate fixtures that are more efficient than what is standard in the market. Otherwise, you are essentially rebating for people to replace something with a fixture they would have purchased anyway. So if a high-efficiency toilet (1.28 gallons per flush) is on the market, customers shouldn’t be rebated for purchasing it because you are not incentivizing an increase in efficiency. They should be rebated for purchasing an ultra-high-efficiency toilet (1.0 gallon per flush or less). Sometimes retail water suppliers will run a one-day toilet giveaway program. In this conservation program, people come to a central location, such as a big park, and pick up a new toilet after providing a driver’s license for identification purposes and a water bill (with a matching name). They are allowed to take the toilet home, but they must return two weeks later to drop off the old toilet to the park (in a giant dumpster) or they will be charged for the new toilet on their bill. This guarantees (almost!) that the new toilet is installed at the home in the service area. This is one model for success but involves a lot of coordination and disposal of old toilets. Misconception Alert! You have probably heard, “If it’s yellow, let it mellow. If it’s brown, flush it down.” Do not do this. Please keep flushing your toilets. This is advice from the 1980s when toilets used 3.5 gallons per flush or more. It wasn’t bad advice then (though still sort of gross), but it’s terrible advice now. Upgrade your old toilet with a 1.28 gallon per flush toilet and keep flushing. We don’t want to keep waste in our homes, and if you have kids, it’s a hard-to-break habit if they learn not to flush. Keep flushing! Showerheads It may be hard to tell how many gallons per minute a showerhead uses just by looking at it. Many showerheads are labeled with this information, but calcium and magnesium in hard water build up to obscure the numbers. In the United States, you can buy showerheads with up to a 2.5 gallons per minute rating, but in California, the only showerhead you can buy is 2.0 gallons per minute or less. To earn a WaterSense label, a showerhead would also need to use 2.0 gallons per minute or less. Shower-Related Conservation Many water agencies have giveaway programs with showerheads. One of the challenges with a giveaway program is that the water agency typically does not know that the product is installed properly (or installed at all). So the water agency may “count” on the savings from purchasing and distributing showerheads, but not necessarily receive the savings as a decrease in overall consumption. Additionally, and equally problematic to conservation program design, showers are seen as “sacred” by many people. It’s their “me” time and they do not want you to mess with their shower, including affecting the quality with a sub-par showerhead and length of shower. Washing Machines A traditional style washing machine uses 40-50 gallons per load of laundry. That’s a lot! A high-efficiency washing machine uses about half of that (20-25 gallons). That’s a significant savings. But, of course, high-efficiency washing machines cost more - typically \$200 more than a traditional machine (as of 2016). A high-efficiency machine typically soaks the clothes longer to remove stains and dirt rather than using a central agitator. The loads of wash may take longer in a high-efficiency machine. Washing-Machine-related Conservation Many water agencies operate washing machine rebates, which offer a rebate of \$100-300 to make the purchase more cost-effective for consumers. Washing machines rebates have mostly replaced toilet rebates in popularity in California. While it’s possible that a customer may receive the rebate and move out of the water agency’s service area, it’s also equally possible that a customer may move in with a high-efficiency machine already. Faucets A standard faucet purchased in the United States uses 2.2 gallons per minute. A WaterSense approved faucet will use 1.5 gallons per minute. Aerators can be added to standard faucets to inject air into the water flow and make the flow seem fuller with less water. Faucet-related Conservation Aerators are typically available at water agencies for free and are given away at events. As with showerheads, aerators are difficult to track and impossible to make sure they are installed properly. They can also present problems in giveaway programs in that customers may need a male or female threaded aerator, but take one of each to hedge their bets. Audits Do you remember the table where you quantified your measurements of indoor fixtures? An “audit” is really an extension of that exercise. You make a list of all the water-using fixtures in the house, quantify their use, decide on a number of times per day, and come up with a total. Completing the table below will help you audit your own home. Try It! Complete the table below to audit your own home (indoor water use). Bathrooms Amount of Water Used per Use Times Used per Day Total Water Used per Day by Device Toilet #1 _____ gallons per flush Toilet #2 _____ gallons per flush Toilet #3 _____ gallons per flush Showerhead #1 _____ gallons per minute Showerhead #2 _____ gallons per minute Showerhead #3 _____ gallons per minute Bathroom faucet #1 _____ gallons per minute Bathroom faucet #2 _____ gallons per minute Bathroom faucet #3 _____ gallons per minute Kitchen Kitchen faucet _____ gallons per minute Dishwasher _____ gallons per use Other Water Using Devices Total Water Used Per Day ______________ In what category is the most water used per day? What could you do to save the most water in your home?

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/03%3A_Demand-Side_Management/3.04%3A_Indoor_Water_Use.txt

How much water is used outdoors? Most estimates for outdoor water use in the United States suggest that it is more than 50% of all water used for residential use. In general, the hotter the locale, the more water is used for landscaping. Learning Objectives In this section, you will: • Identify the benefits and needs of landscape • Differentiate among types of irrigation • Classify plants according to their watering needs • Design a landscape with best practices in mind Why don’t we get rid of all the landscape, cover the ground with cement, and save all that water? Landscape serves a variety of purposes, and is considered a beneficial use of water. After all, plants make oxygen, and we humans love oxygen. Plants also lower the air temperature. An entirely paved landscape would be a hot one - check out the center of a parking lot in the summer. And soil acts as a giant sponge, absorbing and filtering water, which eventually allows for aquifers to replenish. So, keeping landscape is a given, and acknowledging that live plants in the landscapes need water is important. However, choosing a waterwise landscape and giving it just the water it needs is essential. Couldn’t all of our irrigation problems be solved if we saved the rainwater that falls from the sky? Doesn't that just go to waste if it runs into the ocean? We do save it in both surface reservoirs and in groundwater aquifers. Water isn’t wasted if it infiltrates. And even when it runs into the ocean, it is still part of the water cycle. Sometimes, rain barrels are presented as the perfect solution to irrigating landscape. However, rain barrels bring with them a host (no pun intended) of other problems, including providing the perfect breeding ground for mosquitoes. We are poised on having a worldwide explosion of babies with microcephaly, caused by the Zika virus, which is spread by mosquitoes. Additionally, mosquitoes spread the West Nile Virus, and a number of locations in Southern California, including Santa Clarita, are “hot spots” for the disease. It is almost impossible to mosquito-proof a rain barrel—mosquitoes will enter that smallest opening to lay eggs in water. This makes rain barrels perfect for breeding mosquitoes, and not for saving water. Setting mosquitoes aside, why wouldn’t rain barrels help save water? In Southern California, most of the rainfall occurs when the plant water needs are the least. Rain barrels may be a good solution in places like Arizona and New Mexico, which get summer monsoonal storms when the water needs for plants are the greatest. In California, our storm season generally lasts from November through February when the plant water needs are the least. Best Practices in Landscapes It is a much better idea to look beyond rain barrels and beyond eliminating landscape entirely to principles that would help landscape use water more efficiently. These are practices that are a compromise between what is called “all or nothing” thinking. You will hear a lot of this sort of thinking as you hear people talk about their landscape. This is the sort of thinking that says, “If I can’t have my grass in the front and backyard, then I’m going to pave over everything” or “If I can only water twice a week, I’m just going to give up and let everything die.” In the next part, you will learn a few of the principles that landscape professionals use to create and maintain drought-tolerant landscapes. There is a middle ground between paving everything and having no landscape and having turf grass everywhere. Maintain the irrigation system—This means conducting a regular review of the system while it is running to look for common problems (overspray, clogged nozzles, blocked heads). Much like we learned in the section on alternative water supplies, including gray water, frequently maintenance is a hurdle that homeowners do not want to overcome. If something needs maintenance, such as a gray water system or an irrigation system, it may simply be avoided and neglected. There is water-saving potential in conducting maintenance. Mulch the exposed soil—Any surface that is not covered by a plant (or a six inch space around a plant) should be covered with three to five inches of mulch. Mulch has a ton of benefits including keeping the soil temperature more moderate (warmer in the winter and cooler in the summer), preventing weeds from sprouting in soil and decreasing the evaporation. Mulch does need to be raked periodically and re-applied year to year, but it makes a great improvement in the aesthetics and health of a planted surface. Hydrozone—The highest water use plants used in California landscapes are types of turf, including cool season turf, which has slender blades of darker green color, and warm season turf, which has wider blades of medium-green color. You can see in the table below how the water needs, measured in evapotranspiration in inches per day, vary tremendously among types of turf grasses. Typically, when someone admires a lawn, the lawn is Kentucky blue grass or another cool season turf grass. There are low water using options, such as Buffalo grass, which can easily use half as much water. But grass overall is still a very water thirsty plant. Relative Ranking ET in inches/day Cool Season Warm Season Very low < 0.24 Buffalo grass Low 0.24-0.28 Bermuda grass Zoysia grass Medium 0.28-0.33 Red fescue St. Augustine High 0.33-0.39 Perrential Rye grass Kikuyu grass Very high > 0.39 Annual bluegrass Kentucky blue grass Annual rye grass Hydrozoning, or separating your plants by their water needs, helps you water the right amount in each zone. In the table below, you can see how you might group plants according to their high, moderate, low and very low water needs. Each plant is compared to a cool season turf grass of 4-7 inches tall that is not stressed. This is the plant with the highest water need. Trees and shrubs should be in their own zone. Anything drought-tolerant typically has a low water need and should be in a separate zone. And anything with a very low water need typically does not need irrigation. Note that a plant with moderate water needs only needs 40-60% of the water of a cool season turf grass. That means that typically anything other than turf grass will need half as much water - this is truly astounding. Water Needs Percent of Reference ET Types of Plants High 70-90% ET Most turf grasses Moderate 40-60% ET Most trees and shrubs Low 10-30% ET Drought-tolerant plants, like salvia (sages) Very Low <10% ET Cacti Irrigate deeply and water infrequently—Daily watering isn’t necessary for most plants, including turf grass, even during the summer. Irrigation depends on a number of factors, including: Soil type—Both clay and sandy soil in your yard mean you must irrigate in short bursts and allow water to sink in in between bursts. This is typically called cycle and soak because you allow the controller to cycle on once and then let the water soak in before cycling on again. Depth of roots—If you water grass multiple times a day, you train the grass to have short roots, which mean the roots cannot reach other available water deeper in the soil. Try to water less frequently to encourage deeper roots to grow. Seasonal variation—Plants have greater water needs in the summer than the spring, fall or winter. This is intuitive, but many people water the same amount of time all year round. Types of plant material—Would you water your lawn and a cactus the same amount? Of course not. But many people water everything in their yard the same amount, which usually results in over-irrigation of most non-grass plants. This is why separating your yard into hydrozones is so important. Irrigation system type—Spray heads put out water much faster than rotating heads or than drip irrigation - you need to understand this when you program your system. Spray heads and rotating heads can be high-efficiency, meaning they apply water at a slower rate. Spray and rotating nozzles are appropriate for grass, but drip irrigation is a more appropriate choice for shrubs and trees. The table below summarizes the four major types of irrigation, including their water pattern, ideal use, and precipitation (precip) rate, which is the amount of water that the irrigation type puts out. Irrigation Type Water Pattern Ideal for... Precipitation Rate How to irrigate well with it? Spray fan turf grass Faster than soil can absorb Cycle and soak Rotating stream turf grass Faster than soil can absorb Cycle and soak Bubbler gush trees with wells Faster than soil can absorb One run time to fill the wells Drip drip shrubs and trees Same rate soil can absorb One long run time (45 minutes +) Irrigation Controllers In California, any new homes will come with a weather-based or soil-moisture-based irrigation controller. This means that some of the guess work will be taken out of irrigation decisions. Typically people have no idea how much to water and end up over-irrigating everything. Irrigation controllers can be programmed by the days to water, the time of days to water (called the start time), the length of time to water (called the run time). A weather-based irrigation controller or a soil-moisture based irrigation controller needs to be guided on what days to water and what times to start, but can determine how long to water based on weather or on soil moisture. When do you think you might see savings from using a weather-based irrigation controller? Typically, people set their controller at the summer levels for irrigation and keep the controller at that level all year. This means they are watering both more frequently than needed and longer than needed for most of the year. The savings when upgrading to a weather-based irrigation controller come in the spring, fall and winter, when the person was over-irrigating. Grass and Artificial Turf When is grass appropriate? Are people playing on the surface? If so, grass is the perfect plant - no other plant will take being trampled and literally bounce back. If kids or adults are using the grass to play on, keep it. It’s the right plant in the right place at the right time. But the way grass is used in many communities is as a default plant. Grass is easy and inexpensive to install and has been installed in all sorts of places that are hard to irrigate without run-off, like parkways, hills and slopes or medians. What about artificial turf? While artificial turf does not change the landscape aesthetic in a community, it has both benefits and drawbacks, which are detailed in the table below. Benefits of Artificial Turf Drawbacks of Artificial Turf It’s green It can become hot in the sun (and contribute to a heat island effect on your property) It saves water Many installers recommend hosing down artificial turf for dust control and to clean pet waste No mowing is necessary It can photodegrade in the sun (10-year lifespan) No fertilizers are necessary It will smell of pet waste if not cleaned effectively Costs incurred are most likely one time charges (until time for replacement in around 10 years) Typically, artificial turf is \$10-15 a square foot There are other types of outdoor water use, but they are negligible in the greater scheme of things when compared to landscaping. For example, leaks may occur outdoors in the irrigation system. Water can also be used for cleaning hardscape (pavement, sidewalks, driveways), washing vehicles, filling fountains and swimming pools. Try It! 1. Propose a strategy for landscaping an area that you see frequently, such as your home, a local park, or your school. This could be your front or backyard, a common area, or an area at work. Consider the types of plants that you might install, an arrangement for them, the irrigation system you should use, and what obstacles you might encounter along the way. Identify the best practices you have used. 2. A friend wants to install artificial turf in his front and backyard. Give an overview of the benefits and drawbacks of artificial turf. Key Terms Cycle and soak—Irrigating in short bursts and allow water to sink in between bursts Hydrozoning—Separating your plants by their water needs, which helps you water the right amount in each zone

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/03%3A_Demand-Side_Management/3.05%3A_Outdoor_Water_Use.txt

What do a car mechanic and an aerospace engineer have in common? They both work in the Commercial, Industrial, and Institutional (CII) section, which is very diverse in terms of water use. Using water for cleaning as a car mechanic or water for manufacture of aerospace parts are very different uses. As we study CII customers, you’ll be able to bring together what you’ve learned about indoor and outdoor conservation and apply it to the workplace. Learning Objectives In this section, you will: • Classify customers according to type • Identify challenges in the CII sector • Analyze the consumption history of CII customers For CII customers considering conservation, financial incentives are typically a useful conservation tool as well as providing information on the return on investment (ROI). One particular challenge in the CII sector is that a master meter typically provides water for both indoor and outdoor use. Sometimes an entire strip mall of diverse businesses (e.g., nail salon, microlender, lawn mower repair) will be behind the same meter. This makes it very difficult to account for individual commercial water use and to offer appropriate rebates and incentives. With the challenges in the CII sector understood, we will spend some time looking at each type of business within the CII sector. Commercial, Industrial and Institutional Customers Within the commercial, industrial and institutional (CII) sector, water use varies by type of customer. The EPA provides this bar graph of typical water use within different types of commercial and institutional organizations: There are a few key observations you can make, most of which are intuitive: Most customers have a sizable proportion of domestic or restroom water use. This suggests that a program that rebates toilets, urinals, and aerators might be useful to many types of customers. • Schools, offices and hospitality (hotels) use a significant amount of water for landscaping. This suggests that a rebate program for smart irrigation controllers, sprinkler nozzles, landscape audits or checkups or for turf grass removal might be useful. • Some types of customers, such as hospitals or offices, have sizable amounts of water used for heating and cooling (including cooling towers, which can recirculate water). • Kitchens and hotels (hospitality) use a significant amount of water in the kitchen. Commercial Customers Restaurant water use is typically about 50% used in the kitchen, primarily for dishwashing. This suggests that a dishwasher rebate for a water-efficient dishwasher might be in order. And, of course, there is typically a third of total water used for restrooms, which suggests a toilet and urinal rebate program might be well received and needed. Restaurants have other uses of water in the kitchen, including woks and dipper wells, both of which may have continuous flows of water. The next time you are in an Asian restaurant, if the restaurant has an open kitchen, check out the wok. Many restaurants have a continuous flow of water in a faucet behind the wok to use while cooking and to cool the wok. Similarly, dipper wells in ice cream parlors may also have a continuous flow of water to keep the ice cream scoop clean. For kitchen clean-up, pre-rinse spray valves, which are used to pre-clean dishes before going in the dishwasher, can also be upgraded to less gallons per minute, and are a common rebate program. The EPA features a case study in conservation in a restaurant in Chicago, Illinois. The restaurant is called Uncommon Grounds and it conducted three stages of upgrades: 1. Aerators on prep sinks, more efficient pre-rinse spray valves and water only served on request 2. Dishwasher and ice machine upgrades to ENERGY STAR qualified models 3. Rooftop garden with a drip irrigation system that uses a rainwater collection system This case study illustrates that there are a wealth of possibilities for upgrades, but that for restaurants focusing on the kitchen first often makes the most sense. Hotels are another common customer type in the commercial sector. Their water use often encompasses a restaurant, but also restrooms, landscape, and laundry uses. Hotels may have more flexibility for implementing changes for water conservation if they are small and privately-owned or if they have sustainability as part of their mission, such as Kimpton Hotels. Small behavioral changes may be successful for hotels, such as instituting linens/towels re-use options for customers, particularly if customers have to “opt-in” for fresh daily towels or linens. The EPA has a case study in water conservation in a hotel in a Holiday Inn in San Antonio Texas. The water utility spent \$100,000 in a retrofit of guest bathrooms upgrading as shown below: Fixture Original Efficiency Retrofit Efficient Number of Units Toilets 3.5 gpf 1.1 gpf 297 Toilets 5.0 gpf 1.1 gpf 100 Aerators 2.2 gpf 1.5 gpm 397 Showerheads 2.5 gpm 1.75 gpm 397 The hotel achieved an average of 35% savings per upgraded room and \$68,000 in water and sewer costs per year. Industrial Customers The Mid-Continent Ecology Division Laboratory (MED) of the Environmental Protection Agency (EPA) can also be studied as a case study for water conservation. Located in Duluth, Minnesota, the MED is 50 labs, administrative offices, a library, and 7 constant temperature rooms. As with many scientific laboratories, there was a good deal of water used for cooling of scientific instruments. In particular, single-pass cooling occurred not only in the cooling system for the building but for many elements of the research equipment. Because the facility is adjacent to Lake Superior, the facility was able to use waters from the lake for cooling rather than potable water, which reduced its total potable use by 90 percent. Additionally, the water can be returned to Lake Superior after it is used to cool the building or equipment. This use of lake water for cooling is innovative. In California, lakes are much more sporadically occurring than in Minnesota and this would be more of a challenge both in finding a lake to use and in not having detrimental environmental effects. Also, aquatic species tend to like water within a temperature range so any water that is returned to the lake would need to be similar in temperature to the lake water. Institutional Customers Although decreasing water use by 90% in the case of the MED or 35% for the Holiday Inn seems extreme, the types of processes and analyses that occurred at the MED are the sorts of processes that would need to occur are typical of ways to save with other industrial customers as well as institutional customers. Institutional customers are typically schools and universities, hospitals, houses of worship, and city and county agencies. These are typically the sorts of customers who may have many people visiting their facilities for a short period of time. They may also have a variety of different types of use in one building, such as a church that also has a school during the weekdays and group counseling or AA meetings in the weekday evenings. Stanford University is useful as a case study because of the wide-ranging uses of the facility ranging from scientific research to residential housing. At Stanford University, conservation staff met with each department to attempt to quantify water use and potential reductions. Important to this effort was the involvement of stakeholders in the process, which include professors and research staff, but also building and grounds staff who understand how the buildings function, particularly the cooling systems. In the end, a variety of conservation measures were chosen from removal of unnecessary turf grass and installation of weather-based irrigation controllers as outdoor measures to upgrading most bathrooms on campus and replacing one-pass sterilizing equipment, to real-time metering to provide feedback on water use, and especially on leaks. In the same vein as Stanford University, a case study from the EPA found a wide range of possible upgrades for a hospital in Olympia, Washington, to decrease water use. These water conservation measures concentrated on: • Upgrading sterilizer equipment • Recovering condensate from the sterilizer for re-use (non-potable use) • Upgrading water-using equipment with non-water using equipment This process resulted in a savings of 5.9 million gallons once the retrofits were completed and a cost savings of \$140,000 per year. So while it may seem like the CII sector is technical, case studies such as this one illustrate that by identifying the high-water using appliances and equipment and researching upgrades, there is a significant potential for water savings. Try It! 1. Where is most water used in a restaurant? Where is most water used in a school? 2. College of the Canyons is considered an “institutional customer.” Where might the greatest water savings lie?

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/03%3A_Demand-Side_Management/3.06%3A_CII_Water_Use.txt

How do you get people to change? It’s a good question and one with which numerous governmental agencies struggle, particularly those in the health and healthcare fields, where there are the most social marketing campaigns of any field. As you have seen, there are major water infrastructure projects that can be relied on to a certain extent to bring water to the thirsty parts of California. But how can you decrease the amount of water that is needed in the first place? This is called managing demand. You’ve learned a variety of tools from regulation to restrict water use or limit waste, to building codes that require more efficient devices to water loss detection to conservation programs. Decreasing demand is both an art and a science. One additional way to reduce demand is to engage in a social marketing campaign with residents. Learning Objectives In this section, you will: • Differentiate between awareness campaigns and social marketing campaigns • Identify behaviors that most water utilities target • Design a social marketing campaign Typically, public outreach campaigns in the water industry have focused on awareness. That is to say, the campaign wants you to be aware of the importance of water or the amount of water that you use. In the Santa Clarita Valley, a campaign in 2010 focused on residents knowing their "water number," the amount of water that they used in one day. This campaign relied on the jarring realization that the amount of water that people used was much more than they expected. An awareness campaign might also focus on a rebate program by promoting toilet or washing machine rebates. The goal of an awareness campaign is to make more people aware of something, but it isn’t necessarily to make people change their behavior. There isn’t a clear call to action. In the image above, the viewer is made aware that funds are still available for a Cash for Grass Program (called Lawn Replacement). This ad assumes that most people do not know that there is still money available, and is attempting to raise awareness of this. In Southern California, water agencies, such as Castaic Lake Water Agency, frequently have challenges with messaging that contradicts the messaging from Metropolitan Water District of Southern California, which is a much larger wholesale agency. In this case, Castaic Lake Water Agency has funds available for a cash for grass program, while Metropolitan Water District has run out of funds. Customers who do not know who their water wholesaler was were confused about the availability of funds. Success or failure of the campaign could be measured in a change of awareness in rebates with a phone or email survey of a representative sample of residents. Awareness of the rebate could be measured before the campaign launches to establish a baseline (e.g., 20% of residents surveyed in the Santa Clarita Valley are aware there are funds available for the Lawn Replacement Program) and then a follow-up phone survey after the campaign runs for 3-12 months to see if there is any increase in awareness (e.g., 3 months later, 30% of residents surveyed in the Santa Clarita Valley are aware there are funds available for the Lawn Replacement Program). Another awareness campaign that you may have seen is a drought awareness campaign. Most water agencies had to launch some sort of drought awareness campaign that combined with efforts from the State of California to make people aware of the severity of the drought. San Diego County Water Authority has an effective ad to make people aware of state-mandated conservation. Using a modified image from the Drought Monitor of the state of California, the campaign make some suggestions for conservation, but is mostly focused on awareness of the drought and restrictions in place. A similar awareness campaign from the Family of Water Suppliers in Santa Clarita, including Castaic Lake Water Agency, focuses slightly differently on a common misconception: when it rains, the drought is over. This awareness campaign reminds people that just because it rains, the drought is not over. A social marketing campaign differs from an awareness campaign significantly. A social marketing campaign is a campaign that tries to change behavior. By presenting images that motivate people to do the “right” thing (or that poke fun of people doing the “wrong” thing), public agencies can gently move people to better practices that are good for the residents and good for the public agency. However, most of the time, you can’t just tell people to do the right thing. It generally doesn't work. People have too much going on in their lives to listen, unless you make it extremely relevant. You need to have a campaign that refines your message. These are the sorts of questions that are used in campaign planning: • Who are we targeting? • What is our message? • What partnerships will help with our message? • What are the barriers to being understood (or listened to)? During the last drought, many water agencies in California had to tackle how to let people know it was okay to let their lawn get less water and go dormant (yellow). Because green lawns are one way that people tend to rate their status (i.e., I have a green lawn, so I must be financially secure), this is a particularly challenging task. San Diego County Water Authority has a social marketing campaign that tackles this in a unique way. In the image from San Diego County Water Authority, the Authority has chosen to reframe brown grass as “tan” grass, most likely hoping that this will make it seem more appealing. This is a variation of “Brown is the new green,” a phrase made popular by Governor Brown in the same drought, but working with language that may be more appealing (i.e., tan rather than brown). Castaic Lake Water Agency has a similar goal of reducing water use for turf grass, but has taken a different tactic by focusing on the appealing aspects of replacing a lawn (more color, more fun, more time): Many social marketing campaigns have concentrated on the behavior that was prohibited initially during the drought in California, including stopping irrigation run-off, but also refraining from watering sidewalks or washing cars without shut-off nozzles, or using even non-recirculating fountains. While raising awareness of the drought is important, these were all behaviors that were targeted by many water companies in social marketing efforts to behavior change. Try It! 1. Do a quick scan through a newspaper or click through a few websites starting with an online newspaper. Give an example of an awareness campaign and an example of a social marketing campaign. Examples do not need to be from the water industry. 2. Design a social marketing campaign and present your results. Answer these questions: 1. Who are you trying to target? 2. What is the message? 3. What are the hurdles? Key Terms Awareness campaign⁠—A campaign to make more people aware of something, but it isn’t necessarily to make people change their behavior Social marketing campaign⁠—A campaign that tries to change behavior

textbooks/workforce/Water_Systems_Technology/Water_132%3A_Water_Supply_and_Demand_in_California_(Anagnoson)/03%3A_Demand-Side_Management/3.07%3A_Social_Marketing_Campaigns.txt

This textbook is designed to provide the reader with a general understanding of many of the drinking water distribution systems topics. It will also help prepare you for the California Certification Examinations. This chapter will introduce distribution systems and provide information related to becoming a certified operator and the associated regulations. Student Learning Outcomes After reading this chapter, you should be able to: • Explain the general concept of water distribution • Identify the topics of the other chapters within this textbook • State three main goals of a water professional • List the various certification levels of both distribution and treatment operators • Discuss the criteria associated with becoming and working as a certified operator • Explain the content associated with taking a certification examination Introduction to Water Distribution A water distribution system is nothing more than a network of components designed to deliver water from a source to a user. It can be thought of as an array of piping networks and various pieces of equipment taking water from one location and delivering it to another. As a comparison, the human body has a number of different “distribution” systems. The circulatory system, for example, distributes blood throughout the body through a series of organs. You can also look at our roadways as a “distribution system”. You leave your house and follow a path to a destination. In between are turns, signals, signs, etc. Understanding this general description of water distribution systems by no means undermines the complexity of delivering safe and reliable drinking water to consumers. It is merely a broad perspective of the water distribution goal. Take water from one point and deliver it to another. Many people put little thought into the water treatment and distribution processes. The same might be said with electricity. As long as water comes out of the faucet (tap) when you turn it on or lights turn on when you flip a switch, most people seem content and don’t give the delivery process much thought. However, when the water stops flowing, customers take notice of their water service. Even then, the question is “Why is my water off?” and “When will it be back on?” There still isn’t much thought put into the why? Or, very rarely are people interested in the process of water distribution when water service is uninterrupted. The complexities of getting water from its source to the “tap” often go unnoticed. Drinking water originates from various places, but the largest amount of water on the planet can be found in the oceans. Approximately seventy percent (70%) of the surface of the earth is covered by ocean. This corresponds to approximately ninety-six percent (96%) of all the water on earth. There is just one problem. …this water is salty and not suitable for human consumption. There is only a small portion of freshwater (not having salt) that is accessible for sustaining human life. This topic will be discussed in more detail in Chapter 2. Once “fresh” water is accessible, for example diverting water from lakes and rivers or pumping groundwater to the surface, it needs to be transported to communities. A simple description of this process can be broken down into four simple terms, conveyance, treatment, distribution, and customer tap. This may seem like a relatively straightforward and easy process, but there are complexities to this system. These processes (except water treatment) will be discussed in detail in this text. This text is designed to cover these specific aspects of water distribution. They include: • Operator Certification • Sources of Supply • Water Characteristics • Water Quality and Regulatory Compliance • Distribution System Design • Water Main Pipes • Water Valves • Fire Hydrants • Water Meters and Services • Pumping • Water Wells • Water Storage • Cross Connection Control • Safety Water is essential to life. Therefore, water utility employees should always remember the following goals: 1. Provide a safe and potable water supply to the customer 2. Provide a reliable water supply to the customer 3. Provide this water supply at a reasonable cost with excellent service to the customer If you haven’t noticed, the common thread in each of these objectives is the “customer”. It is important for water professionals to understand and realize they are providing a critical service to millions of people throughout the world. Having an understanding of these main objectives helps each employee put into perspective the responsibility associated with being a water utility professional. We are providing a vital service to society. Each chapter in this text will delve into various topics ranging from where our water originates and how it gets to our taps in a safe, reliable, and cost-effective manner. It will focus on the distribution of potable drinking water and the work required to deliver this vital resource. This chapter introduces a general background of how water is delivered and the regulatory framework of ensuring the workforce behind the distribution process is properly trained and certified. Chapter 2 focuses on the source of water, where our water comes from, and the physical, chemical, and biological properties of one of our most precious resources. Chapter 3 enters into the regulatory framework of making our water safe to drink. The discussion will involve how and why drinking water regulations are created and the importance of complying with these ever-changing regulations. Chapter 4 begins the concepts of water distribution network systems. Chapters 5 through 11 build on this concept and begin describing the underground and above ground distribution system components. The distribution system is comprised of pipes, pumps, storage facilities, valves, hydrants, meters, and a vast array of appurtenances (general term for other components), which are interconnected to bring water from the source to the tap. The transportation of water for human consumption has been around for over 3,500 years. The Minoan civilization used tubular conduits to convey water and the Romans used intricate stone aqueduct systems to bring water great distances. In the early 1400s, cast iron pipes were introduced and in the mid-1600s, water flowed through pipes in Boston bringing spring water to what is now known as the Quincy Market area. In the U.S in the 1700s many of the early piping systems were made of bored logs. Advances in technology brought about various advancements in flow technologies and an understanding of how to efficiently and economically treat and distribute drinking water. In 1914, the first drinking water standards were established in the U.S. However, it wasn’t until the early 1970s when the United States Environmental Protection Agency was formed that drinking water quality standards really started to take form. Details regarding drinking water quality will be discussed in Chapter 4 of this text. Although modern water distribution systems in the U.S. are relatively young, the components both under and above ground need maintenance and over time, replacement. In 2014, one of the oldest water systems in the U.S. had a major failure. A 100-year-old pipe in Philadelphia burst, releasing millions of gallons of water. According to the Los Angeles Times, the Los Angeles Department of Water and Power has over 6,730 miles of water main pipes in their distribution network and it is estimated it will cost \$1.34 billion to replace what are considered “at-risk” mains by 2025. What does this mean? It means a few things. First of all, it means there will be plenty of work (jobs) for the foreseeable future in the water utility industry. Second, it means we can expect more frequent and large water main breaks, causing at times severe damage. Lastly, it means the water utility needs to increase the amount of money spent on large improvement and replacement projects, which directly correlates to higher water rates for the consumer. Water treatment and distribution are critical industries for the sustainability of modern civilization. Drinking water treatment and distribution are not the only areas within the world of water, which needs attention. Water is becoming scarcer; therefore conservation efforts will be a way of life, especially in California. We also need to focus our efforts on the wastewater industry. As you will see in Chapter 2, water follows the hydrologic cycle, which means water passes through a continuous cycle from one phase to another. Wastewater is a process within this cycle. Humans consume and use potable water and some of it becomes wastewater. This wastewater must also go through conveyance systems, treatment, and then is discharged back into the environment. The infrastructure associated with conveying and treating wastewater must also be maintained and replaced from time to time. Throughout this text “water companies” will be referred to in a number of different ways. Here are some of the more common terms used: • Water Utility • Water Agency • Water District • Water Company • Public Water Supplier • Urban Water Supplier • Water Retailer • Water Purveyor • Public Drinking Water System Do not get confused with all these different terms. In essence, they all mean the same thing. The reason there is a variety of ways to identify a company that delivers water has to do with how they are governed and how they are identified in various regulations. Just understand in this text if you read any of these terms (or possibly others), realize we are discussing the same thing. State Water Resources Control Board In California, regulations governing water distribution and treatment fall under the Division of Drinking Water (DDW) within the State Water Resources Control Board (SWRCB). The reason both agencies are identified separately is that the breadth of authority expands beyond drinking water for SWRCB. DDW regulates public water systems and is broken into three branches, the Southern California Field Operation Branch, the Northern California Field Operation Branch, and the Program Management Branch. Each branch has its own set of responsibilities and authority. In addition to drinking water, the SWRCB is also responsible for the Regional Water Quality Control Boards (RWQCB) and functions as the regulatory authority for surface water quality and surface water rights. Field Operations Branches The Southern and Northern Field Operations Branches (FOB) within DDW are responsible for the enforcement of the federal and state Safe Drinking Water Acts (SDWA). They have oversight of approximately 7,500 public water systems. Their primary responsibility is assuring the delivery of safe drinking water to Californians. The following is a list of some of the main functions of FOB staff: • Issue operating permits • Review plans and specifications for new facilities • Review water quality monitoring results • Issue enforcement actions for non-compliance • Conduct field inspections • Promote water system security FOB staff also work on recycled water projects, conservation efforts, and source water assessments. Although each FOB is empowered with the regulatory and enforcement authority over public water systems they carry the same goal and typically work closely with water industry professionals on providing safe and reliable drinking water. They provide review and oversight of water-related infrastructure plans and they conduct field inspections giving guidance of how a proper distribution system should be operated. Program Management Branch The Program Management Branch (PMB) within DDW works separately from the FOBs. Typically PMB staff do not work as routinely with public water system staff as the FOBs. They are charged with collecting, compiling, evaluating, and reporting water quality data from laboratories that monitor drinking water for public water systems. The PMB also coordinates emergency response and associated training and provides advice on technical matters associated with drinking water contaminants. There are two additional sections under the PMB, the Environmental Laboratory Accreditation Program Section (ELAP) and the Technical Operations Section (TO). ELAP is responsible for evaluating and accrediting water quality testing laboratories to ensure the quality of the analytical data used for regulatory purposes to meet the requirements of the State’s drinking water. TO prepares the Annual Compliance Report for the United States Environmental Protection Agency (USEPA), analyzes proposed drinking water-related legislation, provides information and reports on fluoridation by public water systems and oversees the Drinking Water Additives Program. The above descriptions and tasks associated with DDW are in no way an exhaustive list. However, it should provide the reader with a basic understanding of the overarching regulatory framework governing public water systems. In addition, to the jurisdictional authority of DDW and SWRCB, other applicable laws and standards within California legislation covering public water systems will not be discussed in this text. Operator Certification Another function of DDW is of operator certification. Although the USEPA SDWA was not promulgated until 1974, laws and regulations governing the certification of potable water treatment facility operation were enacted in 1971. These rules established the level the water treatment facilities should be manned, the minimum qualifications for testing at each of the five grade levels, and the criteria for the renewal and revocation of operator certificates. However, it wasn’t until 1996, as part of the SDWA Amendments, that regulations pertaining to operator certification were enacted. In 1998, the USEPA used these amendments to establish guidelines for the certification and re-certification of operators of public water systems. These guidelines established five (5) different certification levels for both water distribution and water treatment operators. This section of the text will focus on distribution operator certification. However, the drinking water treatment certification criteria are similar. In addition, there are certifications for wastewater as well. In drinking water, there are five (5) certification levels for both distribution and treatment (1 – 5). A level one (1) certification is the lowest and level five (5) the highest. The distribution certification levels are as follows: Distribution D1, D2, D3, D4, D5 The operator certification regulations provide specific requirements that water utilities and their employees must follow. Title 22 regulations state “all suppliers of domestic water to the public are subject to regulations adopted by the USEPA under the SDWA as well as by the SWRCB DDW under the California Safe Drinking Water Act (CSDWA).” Title 22, Division 4, Chapter 13 identifies these requirements. Each water utility is designated a certain distribution and/or treatment classification. This classification is based on a variety of different parameters. For example, a distribution system has a classification based on things such as: • Number of service connections • Number of sources and types of supply • Number of storage facilities • Type(s) of disinfection processes and chemicals used There are other criteria, but these are the main benchmarks used to set the classification. Once the system has its classification, it determines the level of certification the operators must obtain. There are two types of operators; Chief and Shift. Article 1, Section 63750.25 of the above-referenced chapter in Title 22, defines a Chief Operator as “the person who has overall responsibility for the day-to-day, hands-on, operation of a water treatment facility or the person who has the overall responsibility for the day-to-day, hands-on, operation of a distribution system.” Section 63750.70 defines a Shift Operator as “a person in direct charge of the operation of a water treatment facility or distribution system for a specified period of the day.” There are specific requirements in order to become certified, which will be discussed later in this Chapter. Below is a table showing the minimum certification requirements for Chief and Shift Operators based on the classification of a distribution system. Distribution System Classification Minimum Certification of Chief Operator Minimum Certification of Shift Operator D1 D1 D1 D2 D2 D1 D3 D3 D2 D4 D4 D3 D5 D5 D4 In addition to a Chief and Shift Operator, there are day-to-day operators who work for water utilities, but do not have any authority or decision-making responsibilities. These operators are still required to become certified, but they can hold any level based on their agency's requirements. For example, if a water utility is classified as a D5 distribution system, the employees can become D5 Distribution Operators, but may not necessarily be listed by the utility as the Chief Operator. There are specific requirements in the regulations stating what types of activities must be performed by a certified operator. A distribution water system must use only certified operators to make decisions addressing: • Installing, tapping, re-lining, disinfecting, testing, and connecting water mains and appurtenances • Shutdowns, repairs, disinfecting, and testing broken water mains • Flushing, cleaning, and pigging existing water mains • Stand-by emergency response duties for after-hours distribution system operational emergencies • Draining, cleaning, disinfecting, and maintaining distribution reservoirs • Determining and controlling proper chemical dosage rates for wellhead distribution residual maintenance • Investigating water quality problems in the distribution system While reading the above activities, some of you may be wondering what some of these terms mean. Don’t worry; they will all be addressed later in this text. Examination Certification Eligibility Criteria Not just anyone can become a certified operator. There are eligibility criteria for taking operator certification examinations. These criteria include completion of approved courses related to distribution and/or treatment topics, experience working in the industry with a distribution system and/or treatment plant, and holding a high school diploma or GED. A general description of the criteria for each certification level is as follows: D1 Certification – You must have a high school diploma or GED. Although no experience is required, specific experience can be substituted for a high school diploma or GED. If you do not hold a high school diploma or GED equivalent, you must successfully complete the “Basic Small Water Systems Operations” course provided by DDW, or have one year or more experience as an operator of a facility that required an understanding of chemical feeds, hydraulic systems, and pumps. D2 Certification – You must meet the requirements of a D1 certification exam plus at least one course of specialized training covering the fundamentals of drinking water distribution or treatment. D3 Certification – You must meet the requirements of a D1 certification exam plus at least two courses of specialized training. At least one of the courses must cover the fundamentals of drinking water distribution or treatment. D4 Certification – You must have a valid D3 operator certificate plus at least three courses of specialized training. At least two of the courses must cover the fundamentals of drinking water distribution or treatment. D5 Certification – You must have a valid D4 operator certificate plus at least four courses of specialized training. At least two of the courses must cover the fundamentals of drinking water distribution or treatment. In some instances, advanced degrees such as an Associate or Bachelor’s degree can be used to fulfill operator experience. The degrees must be in specific disciplines and they only fulfill a certain amount of operator experience. Operator Certification Examination Content Anyone who wishes to take an operator certification examination must meet the criteria explained above and complete the required application. This sounds easy enough. The trick is you must pass an exam in order to become certified. DDW provides the expected range of knowledge for each certification examination level. These include the following and can also be found here: • Disinfection • Distribution System Design and Hydraulics • Equipment Operation, Maintenance, and Inspections • Drinking Water Regulations, Management, and Safety • Water Mains and Piping • Water Quality and Water Sources • Water Treatment Processes • Laboratory Procedures • Regulations and Administration Duties Each one of these categories includes an array of information and topics. Textbooks like this one and courses offered at colleges, water-related organizations, and private companies provide the information needed to pass certification examinations. The operator certification information provided in this Chapter should provide you a general understanding of the operator certification guidelines and regulations. However, there is much more detail available regarding this topic. The following uniform resource locator (URL) will take you to the SWRCB website regarding Operator Certification. There you will find specific information regarding the regulations, expected range of knowledge, examinations, schedules, applications, fees, renewals, frequently asked questions, and more. While each type of certification exam will focus primarily on the main discipline (distribution or treatment), there are overlapping topics. Drinking Water Distribution & Treatment System Operators The following link is a source of guidelines for Drinking Water Treatment &amp; Distribution System Operators. Sample Questions 1. In order to take the D1 exam, you must ___________. 1. Have successfully completed one 3 unit course 2. Have a high school diploma or equivalent 3. Successfully completed two 3 unit courses 4. Both 1 and 2 2. SWRCB stands for ___________. 1. Safe Water Regional Control Board 2. State Water Regional Control Board 3. State Water Resources Control Board 4. Safe Water Resources Conservation Bureau 3. A utility worker who is in direct charge of the operation of a water distribution facility for a specified period of a day is considered a ___________. 1. Chief Operator 2. Shift Operator 3. Distribution Operator 4. All of the above 4. There are ___________ levels in water distribution certification. 1. 2 2. 3 3. 4 4. 5 5. The transportation of water for human consumption dates back to ___________. 1. 500 years 2. 1,500 years 3. 2,500 years 4. 3,500 years 6. A common element in the delivery of water to customers is the distribution framework. 1. True 2. False 7. The Division of Distribution Water is the governing body for water utilities in California. 1. True 2. False 8. Advanced degrees such as Associate and Bachelor’s can be sometimes used to fulfill experience requirements. 1. True 2. False 9. Which one of the following regulations encompasses the California State Drinking Water Act? 1. Title 11 2. Title 22 3. Title 33 4. Title 44 10. Which one of the following would not be considered a main goal of a water professional? 1. Provide a safe and potable water supply to the customer 2. Provide a reliable water supply to the customer 3. Provide this water supply at a reasonable cost with excellent service to the customer 4. Ensure your public retirement pension is fully funded

textbooks/workforce/Water_Systems_Technology/Water_140%3A_Water_Distribution_Operator_I_(Alvord)/1.01%3A_Introduction_To_The_Operator_Certification.txt

This chapter will discuss the sources of water in California and the characteristics of water. Student Learning Outcomes After reading this chapter, you should be able to: • Explain the different stages of the hydrologic cycle • Identify the various sources of supply • List the primary sources of supply for the Southern California area • Discuss the physical, chemical, and biological aspects of water Hydrologic Water Cycle Where does our water come from? One of the most unique aspects of our planet is the vast amount of water covering it. About seventy-one (71) percent of the earth’s surface is water. The very thing that is essential to sustain life covers almost three-quarters of our planet. However, approximately ninety-seven and a half (97.5) percent of all the water on earth is saltwater. This equates to about three hundred twenty-six (326) million trillion gallons of water, which is not suitable for drinking. This means two and a half (2.5) percent of the planet’s water is freshwater, or water not containing salt. While this is still a lot of water, almost seventy (70) percent of it is inaccessible. This water is in the form of glaciers or permanent snow cover. Approximately thirty-one (31) percent of this water is groundwater and less than one (1) percent is considered surface water. Does this mean we will eventually run out of freshwater? If the majority of the earth’s water is either saltwater or inaccessible, does it mean we have a limited supply to sustain life? The short answer is no, we will not run out of freshwater and we do not have a limited supply. However, access to freshwater is an issue that needs to be addressed, and there are places on our planet that lack safe and adequate supplies of drinking water. In this section, we will address the “short answer”. The reason we have access to freshwater in most areas on earth has to do with something known as the hydrologic cycle. The hydrologic cycle is the continuous movement of water throughout the earth. It is the physical process of evaporation, condensation, precipitation, infiltration, and surface runoff. Water changes from one form to another and then another. The three phases that water passes through are liquid, gas, and solid. We understand and encounter water in these three phases on a daily basis. Water in its most common form is liquid. However, we can freeze it to make ice (solid) or boil it to encounter steam (gas). Throughout the hydrologic cycle, water also transfers through these phases. The image below (courtesy of the United States Geological Survey - USGS) shows a lot of detail regarding the hydrologic cycle. First, try to focus on the three phases we just discussed (liquid, gas, and solid). Precipitation is the liquid state, ice and snow the solid state, and evaporation represents the gas or vapor state. As you can see from this diagram, it is a little more complicated, but water passes through these three phases (states) in a continuous movement on, above, and below the surface of the earth. There are three (3) other terms you should become familiar with in this process. The terms are evapotranspiration, infiltration, and sublimation. Evapotranspiration is the process of water transferring from the land to the atmosphere from the soil and other surfaces and by transpiration from plants. Transpiration is the evaporation from plant leaves. Think of it as plants sweating. Sublimation is the process by which a substance (water in this case) passes directly from the solid phase to the vapor or gaseous phase. This typically happens in the atmosphere. The third term is infiltration. Infiltration is the process of water entering the ground surface. If geological conditions are right, the water will continue transferring deeper into the earth’s surface until it becomes groundwater. This deeper transferring process is known as percolation. The only other process in the hydrological cycle you should take note of is the process of condensation. This is when water vapors transition from the gas phase to the liquid phase. Now that we have a general understanding of the hydrologic cycle, it’s time to turn our attention to the various sources of water supply. Water Sources Surface Water As water leaves the oceans and other areas on land, it evaporates into the atmosphere and eventually comes back down through some form of precipitation. As snow and ice melt or rain falls on land it becomes runoff. This runoff will enter streams, rivers, or lakes. These are considered surface water. There are three (3) main surface water sources of supply in southern California, State Water Project, Colorado River Aqueduct, and Los Angeles Aqueduct. Each of these surface water sources serve specific areas and are owned and operated by different water agencies. • Los Angeles Aqueduct – The LA Aqueduct is owned and operated by Los Angeles Department of Water and Power (LADWP). The only users of this water are the customers of LADWP. The aqueduct took approximately five (5) years to construct and originates in the Owen’s Valley, bringing water to LADWP customers through an all gravity system. • Colorado River Aqueduct – The Colorado River Aqueduct brings water from the Colorado River at Lake Havasu to Southern California. It is operated by Metropolitan Water District. The water flows through two (2) reservoirs and five (5) pumping stations and delivers water as far south as San Diego County. • State Water Project – The State Water Project is one of the largest public water utilities in the world. It brings water from Northern California and distributes it to areas in and around San Francisco and to the major metropolitan areas of Southern California. It is maintained by the California Department of Water Resources and has twenty-nine different contractors pulling water from this system. There are more than a dozen water storage reservoirs and pumping plants within this system. According to the USGS, approximately eighty (80) percent of all water used in the United States comes from surface water sources. Surface water is an important natural resource used for many purposes, especially irrigation and public drinking water supply. Groundwater Groundwater is water on the surface, which infiltrates and eventually percolates deep enough into underground systems known as aquifers. An aquifer is an underground system of permeable soil (sand, gravel, rock), which can contain and transmit water underground or groundwater. Groundwater exists for two main reasons, gravity and geologic formation. Gravity pulls the water into the earth and if the geologic formation is conducive to holding water, aquifers will form. Water accumulates in the voids and spaces within the underground geology. Some examples of these formations consist of sandstone, limestone, and even granite. There are three (3) main types of aquifers, unconfined, confined, and fractured rock. Each of these has unique characteristics and properties. • Unconfined Aquifer – An unconfined aquifer has the upper surface open to the atmosphere through permeable material such as sand and gravel. This type of aquifer is typically more susceptible to contamination from spills or discharges on the ground surface. • Confined Aquifer – A confined aquifer has a similar composition as unconfined aquifers. They consist of porous materials such as sand and gravel. The main distinction is there is an overlying impervious rock or clay layer separating it from the atmosphere. Commonly, this impervious layer consists of clays. Because of this impervious layer, confined aquifers are generally less susceptible to contamination. • Fractured Rock – An underground fractured rock aquifer system is much different than unconfined and confined aquifers. In some areas, there are rock formations, which have little to no permeability, but they still can contain water. The water is stored in complex fractures (cracks) within the rock formation. This water can be withdrawn, but the variability of the fractures makes it more difficult to locate the areas with water. Both unconfined and confined aquifers can yield large quantities of water for domestic and agricultural use. Many communities rely solely on groundwater from these types of aquifers. While fractured rock can store water underground, these types of aquifer are not as common and do not produce nearly as much water. In the Southern California area, there are many different aquifers systems. According to the California Department of Water Resources (DWR), there are seventy-seven (77) groundwater basins and subbasins in the South Coast Hydrologic Region. This includes the counties of Ventura, Los Angeles, San Bernardino, Riverside, Orange, and San Diego. Recycled Water Another source of supply, which is becoming more prominent and needed is recycled water. In the past, the term “reclaimed” water was used more frequently. This was due in part to the source of the water, water reclamation plants. However, as the use became more prevalent, the term recycled became more common. They are interchangeable. Recycled water is treated wastewater. All wastewater travels through a network system of sewer pipelines. This network is primarily a gravity flow system, but at times when elevations change, pumps are required to “lift” the wastewater. Once the wastewater arrives at a wastewater reclamation plant (wastewater treatment plant is also commonly used), it must go through a treatment process. The treatment requirements for ultimate discharge vary depending on where the treated wastewater will be released. Sometimes these treatment plants are located along the coast and the water is discharged to the ocean. While other times, plants are located in inland communities and the water is discharged in local river systems. In order for treated wastewater to be used as recycled water, it must at least go through tertiary treatment. The first two stages of wastewater treatment (primary and secondary) are designed to remove the debris and solids through a sedimentation process and then a process to remove the biological content. The tertiary treatment process is usually the last stage of treatment unless some form of advanced treatment is used. Typically this process involves some form of filtration, which includes sand. Additional nutrients can also be removed. While recycled water typically meets all state and federal drinking water standards, it is not allowed for human consumption. The primary use of recycled water is irrigation. Parks, playgrounds, sports fields, street and freeway landscaping, and golf courses are some of the more common uses of recycled water. Recycled water can also be used for industrial and commercial cooling systems. Water Characteristics Water is an amazing compound and has some very unique properties. Because of the molecular structure of water, it has an affinity for other molecules. Water is considered a “polar” compound. This means there is an uneven distribution of the electron density. The bonds between the oxygen atom and two hydrogen atoms are at an angle (see below). The red dot above represents the oxygen atom in water and the two white dots represent the hydrogen atoms, which equates to the molecular formula “H2O”. The structure of water has a partial negative charge near the oxygen and partial positive charge near the hydrogen atoms. This structure allows water to have both cohesion and adhesion properties. Cohesion is the ability of water to be attracted to other water molecules. This cohesive property is what gives water surface tension and allows insects such as a Water Strider to walk on water. This polarity also allows water to dissolve many different compounds. Water also has an attraction between molecules. This property is referred to as adhesion. When you fill a glass with water the water around the glass “adheres” to the glass causing the water to “climb” the glass wall. This results in the water having a meniscus a concave appearance. Water is also the only common substance on the earth’s surface, which exists as a gas, liquid, and solid. Temperature effects water by causing it to persist in each one of these phases. It is typically a colorless and odorless substance. Physical Characteristics Water is generally colorless. This is one of the most important aesthetic qualities of water, which customers care about. No one wants to drink water that has a color. However, this is also a common problem water quality professionals have to monitor. There are several things in the distribution system, which can cause water to have a color. Some examples include air (white), iron (yellow or brown), manganese (causing black stains). There are solutions to these examples, but it is important for water utility professionals to monitor their water quality within the distribution system in order to keep water in its natural colorless state. In addition to being colorless, water typically doesn’t have a taste. However, much like color, certain things in the water supply can give water an unpleasant taste. Chlorine is a chemical commonly used to disinfect water in order to make it safe to drink. However, this can also give water an unpleasant taste to customers. The final physical property of water we will discuss in this text is temperature. As the temperature of water changes, the physical nature of water also changes. For example, as water approaches 0°C it changes form from a liquid to a solid. Conversely, as water approaches 100°C, it starts to boil and transitions from a liquid to a gas. Sample Questions 1. Which one is not one of the phases of water throughout the hydrologic cycle? 1. Liquid 2. Gas 3. Solid 4. Sublimation 2. Treated wastewater used for irrigation is termed ___________. 1. Non-potable water 2. Irrigated supply water 3. Agriculture water 4. Recycled water 3. Water is generally ___________. 1. Colorless 2. Unsafe to drink 3. Abundant in all areas 4. All of the above 4. Which of the following would not be considered an aquifer? 1. Confined 2. Unconfined 3. Aqueduct 4. Fractured rock 5. The three main surface water sources of Los Angeles include all of the following except ___________. 1. Los Angeles Aqueduct 2. Columbia River 3. Colorado River 4. State Water Project

textbooks/workforce/Water_Systems_Technology/Water_140%3A_Water_Distribution_Operator_I_(Alvord)/1.02%3A_Sources_and_Characteristics_of_Water.txt

Student Learning Outcomes After reading this chapter, you should be able to: • Differentiate between the primary sources of drinking water contamination • Evaluate the water quality sampling requirements within a distribution system • Summarize the main federal and state water quality regulatory citations • Explain the role the American Waterworks association plays in terms of water quality standards Is My Water Safe to Drink? One of the biggest questions and concerns people have is whether or not their tap water is safe to drink. However, sometimes there is confusion between the taste, odor, and appearance of the water and the actual “safety” of the water. Many times these two things are not one and the same. Tap water can be discolored, smell strange, and have an odd taste, but from a health and safety standpoint, the water might be perfectly fine. Explaining this to a customer can be a very challenging task. Conversely, a glass of water might be crystal clear and have no apparent taste or odor and could be potentially unsafe (non-potable) for human consumption. So, how does a water quality professional handle variability in the quality of drinking water? There are several things (tools in a toolbox) water treatment and distribution operators use to make sure the water they are providing to millions of people is safe and to a certain extent “pleasant” to drink. The word pleasant is placed in quotes because things like taste, odor, and color can be very subjective characteristics in terms of drinking water quality. The tools water utility professionals use can be explained in four main categories; regulations, treatment, testing, and maintenance. Each one of these will be explained throughout this chapter, but below is a concise explanation of each one. • Regulations – Drinking water quality regulations might be the number one component to ensure a safe drinking water supply is being provided to water utility customers. The United States Environmental Protection Agency (USEPA) is tasked with providing minimum drinking water standards for water utilities throughout the United States to adhere to. These drinking water regulations are found in the Safe Drinking Water Act (SDWA). Among other things, the SDWA sets minimum levels for a variety of contaminants in drinking water. • Treatment – Within the SDWA, there are rules and regulations regarding the treatment requirements at drinking water treatment plants. Along with the minimum contaminant levels, there are various treatment technologies for drinking water treatment plants. • Testing – The SDWA also spells out testing requirements for water utilities at treatment plants, at the various sources of supply, and within distribution systems. Additional sampling is also common for a variety of other reasons not spelled out in the regulations. Collecting and analyzing water quality samples is not only a regulatory requirement, it is used by treatment and distribution operators for monitoring and predicting water quality. • Maintenance – Maintenance (especially within distribution systems) goes a long way with improving and maintaining good water quality. Some of the more common distribution maintenance tasks associated with improving and maintaining good water quality are flushing of water mains and cycling the level of water in storage tanks. Providing and maintaining a safe supply of drinking water to customers is a primary responsibility of all water utilities. This is achieved through the items discussed above as well as a collaborative and coordinated effort between water utility staff, regulators, and the public receiving this vital resource. In addition to the regulatory requirements, the American Water Association (AWWA) provides a variety of standards and guidance to water utilities. AWWA is an international, nonprofit, scientific, and educational organization. It was established in 1881 and is the largest Association of water supply professionals in the world. The recent State Water Resources Control Board Division of Drinking Water’s (DDW) waterworks standards were revised in 2008 and most were based on AWWA recommendations and standards. Sources of Contamination There are a number of naturally occurring and manmade contaminants, which can be found in water supplies. These contaminants can be broken down into four (4) main categories; physical, biological, chemical, and radiological. Because the sources of drinking water supply vary from region to region, the contaminants present in one part of the world are not necessarily found in other parts of the world. For example, a constituent, such as fluoride, is temperature-dependent and therefore is not typically found in groundwater supplies in cooler regions but may be found in warmer climate regions. Physical Contamination Most physical contaminants do not pose a direct health effect. They primarily impact the appearance of drinking water. Physical contamination is more commonly found in surface water supplies and often results from soil erosion. Sediments and organic material can wash off surrounding hillsides along lakes, rivers, and streams. These contaminants mostly affect the aesthetic quality of drinking water, such as taste, odor, and color. However, these types of contaminants can also impede the drinking water treatment process and can act as a barrier, protecting biological contaminants. Biological Contamination One of the most common contaminants water utilities collect samples and analyze are part of the biological class of contaminants. While only a few bacteriological organisms are pathogenic, this entire class of organisms can wreak havoc on a water system. From a public health standpoint, we are mainly concerned with the bacteriological and viral disease-causing (pathogenic) organisms. Since it can be difficult and costly to try and analyze all the different strands of viruses and bacterial organisms, which might find their way into a water system, an “indicator” organism is preferred. In drinking water supplies and systems, the indicator of choice is the total coliform group. Pathogenic organisms include those derived from fecal contamination and viruses, which typically use bacteria as a host for replication. These disease-causing organisms that can be found in drinking water include, but are not limited to Escherichia coli (E. coli) and various strains of Vibrio and Enterococcus, various enteroviruses, and parasites such as Cryptosporidium and Giardia. Most of these organisms find their way into a drinking water system through some type of contamination with fecal matter. Perhaps an animal feed lot is upstream from a water supply or an underground sewer collection system is leaking next to a drinking water underground well. Therefore, the main source for these contaminants is human or animal feces. All of these potential contaminants are routinely monitored through a regulation called the Total Coliform Rule (TCR). In 2013 and 2014, revisions to the 1989 TCR were implemented in order to improve public health. The TCR is now referred to as the Revised Total Coliform Rule (RTCR). Total coliforms are a group of related bacteria, which are (with few exceptions) not harmful to humans. Therefore, the USEPA has identified this group of organisms to represent an indicator for a variety of bacteria, viruses, and parasites which are known pathogens and can cause health problems in humans if they are ingested. Revised Total Coliform Rule The USEPA published the Revised Total Coliform Rule (RTCR) in the Federal Register on February 13, 2013 (78 FR 10269) and minor corrections on February 26, 2014 (79 FR 10665). Promulgation of the RTCR began on April 1, 2016. Most of the major provisions of the TCR stay in place and include: • Collecting total coliform (TC) samples at representative locations throughout the distribution system. • Samples must be collected at regular intervals. • Numbers of samples collected are based on the size of the population the water utility serves. • Repeat sampling is required for positive results, which include analysis of E. coli. Details of the TCR can be found in the USEPA’s Total Coliform Rule: A Quick Reference Guide. The main changes to the RTCR include the following: • Setting a maximum contaminant level goal (MCLG) and maximum contaminant level (MCL) for E. coli. • Setting a TC treatment technique (TT). • Requirements for assessments and corrective actions. • Specific language in the annual Consumer Confidence Reports (CCR) for violations. Details of the RTCR can be found in the USEPA’s Revised Total Coliform Rule: A Quick Reference Guide. There are a number of different provisions within each rule and depending on the size of the utility, there are different requirements. In general, every TC positive sample must be followed up with analysis of E. coli and repeat samples are also required. At least three (3) repeat samples are required for every TC positive sample. The repeat samples must be collected within 24 hours of learning about the positive TC result. The repeat samples must be collected from the same sample location and within five (5) service connections upstream and downstream of the original sample location. There are additional requirements, but more detail is beyond the scope of this text. Chemical Contamination There are many different chemicals used in the world for a variety of different things. For example, arsenic is used to preserve wood and prevent rotting and chromium is used in chrome plating processes. While chemicals are commonly used in various manmade processes, they are also found naturally occurring in the environment. Regardless of the source of contamination (naturally occurring or manmade), if they pose a threat to public health they also need to be regulated if they are found in drinking water supplies. Within this group of contaminants, there are two main categories; inorganic and organic. The main difference between these two categories is the absence of carbon with inorganic chemicals and the presence of carbon with organic chemicals. Below is a short list of common contaminants found in drinking water supplies within both categories. • Common Inorganic Chemicals – While most of these inorganic chemicals can be found naturally occurring in water supplies, with the exception of arsenic, most are the result of contamination from human activities. • Arsenic (As) – As previously mentioned, one of the main uses of arsenic is preserving wood. Arsenic is also commonly found naturally in groundwater supplies, especially in the southwest. • Nitrate (NO3) – While nitrate can be found naturally occurring, these levels are relatively harmless. The primary sources of nitrate in drinking water are from fertilizers and contamination from sewage. • Chromium (Cr) – Chromium is used in plating processes and can also be found naturally in the environment. One of the unique things about chromium is it is found in two common oxidative states, Cr III and Cr VI. • Lead – Lead is most commonly found in plumbing systems, although the allowable levels are being reduced because of the significant health effects. The main reason lead was used in plumbing supplies is because of its malleability. • Copper – Copper is also most commonly found in plumbing supplies • Common Organic Chemicals – The organic chemicals found in drinking water supplies are referred to as volatile organic compounds (VOCs) and synthetic organic compounds (SOCs). While they can be found naturally occurring, the majority of the VOCs and SOCs found in drinking water supplies are from manmade chemicals. • Trichloroethylene (TCE) – TCE is a common solvent used as a degreaser • Tetrachloroethylene (PCE) – PCE is a common solvent used in dry cleaning • Methyl tertiary-butyl ether (MTBE) – A gasoline additive to help improve air quality Drinking Water Standards In order to make sure contaminants are limited or kept at levels below those which would pose health effects to consumers, there are a number of regulatory standards in the SDWA. In addition to the federal SDWA, some states have their own set of standards water utilities must adhere to. In California under Title of the California Code of Regulations, there is the California Safe Drinking Water Act (CSDWA). The difference between federal and state drinking water regulations is the ability of state regulations to be more stringent than federal regulations. This means that the CSDWA can have regulatory levels for contaminants set at a lower level than the federal SDWA. They cannot be set higher. Within the SDWA, contaminants are separated into two main categories, primary drinking water standards and secondary drinking water standards. Primary standards are for those chemicals which pose a public health threat. Secondary standards are for contaminants, which have aesthetic effects on the water supply. The USEPA goes through an extensive process in order to determine if a contaminant needs to be regulated under the SDWA. There are three (3) main criteria the USEPA considers in order to make a regulatory determination. They determine whether or not the contaminant meets the following criteria: • The contaminant may have an adverse effect on the health of persons • The contaminant is known to occur or there is a substantial likelihood the contaminant will occur in public water systems with a frequency and at levels of public health concern • In the sole judgment of the Administrator, regulation of the contaminant presents a meaningful opportunity for health risk reductions for persons served by public water systems Once the USEPA identifies whether or not a contaminant needs to be regulated, further evaluation is required to determine the technical and economical feasibility of regulating the contaminant. During this process, a non-enforceable level is usually established. This non-enforceable level is referred to as a Maximum Contaminant Level Goal (MCLG). MCLGs are set at levels which no known or anticipated adverse health effect would occur. The next step is to develop an enforceable standard referred to as a Maximum Contaminant Level (MCL). MCLs are set as close to the MCLG as is feasible. The SDWA defines “feasible” as the level that may be achieved with the use of the best available technology or treatment techniques the USEPA finds available (under field conditions and not solely under laboratory conditions), taking cost into consideration. The USEPA can establish a regulatory treatment technique when there is no reliable method that is economically and technically feasible to measure a contaminant. In addition to MCLs and MCLGs, there are other acronyms related to drinking water quality regulations. These include the following: • PHG – Public Health Goals are similar to MCLGs. They are California non-enforceable standards where an MCL does not exist. • AL – Action Levels are set for certain contaminants where an MCL does not exist and some type of response (action) is required by the water utility if an AL is exceeded • DLR – Laboratories are tasked with analyzing contaminants. As laboratory techniques improve, these levels become smaller (lower) over time. The Detection Limit for Reporting is set at a level laboratories can accurately reproduce with the current method of analysis. The level of a contaminant is expressed using a ratio of units. The most common units used to express levels of contaminants are the following: • Milligram per liter (mg/L) • Microgram per liter (ug/L) • Nanogram per liter (ng/L) The above examples express the weight of the contaminant in a liter of water. Therefore, a level of 10 mg/L means that for every liter of water there are 10 mg of a substance. Sometimes, alternative units of measure are used. These alternatives are the following: • Parts per million (ppm) = mg/L • Parts per billion (ppb) = ug/L • Parts per trillion (ppt) = ng/L These units mean for every part of a contaminant there are a million, billion, or trillion parts of water. For example, a level of 10 ppm (same as 10 mg/L) means that for every million parts of water, there are 10 parts of the substance. While it is not required for water distribution operators to memorize drinking water quality standards (MCLs), it is important for them and especially the water quality professionals to have a general understanding of the main contaminants within their water supply. In addition, it is important for water quality professionals such as water quality technicians, specialists, supervisors, and managers to understand the health effects associated with common contaminants. Some of the more commonly found primary contaminants in drinking include the following: Nitrate Nitrate – MCL = 45 mg/L as NO3 or 10 mg/L as N – The reason there are two MCLs for nitrate is because the value can be expressed as actual amount of nitrate (NO3) or expressed as the total amount of nitrogen (N). • Source – The primary source of nitrate in drinking water is from fertilizers. This is especially present in areas where there is or was agriculture present. Nitrate can also occur as a result of contamination from animal or human sewage waste. • Health Effects – The primary health effect associated with elevated levels of nitrate in drinking water is something referred to as “blue baby syndrome”. The medical diagnosis is methemoglobinemia. It is a condition, which effects the body’s ability to release oxygen to tissues. Infants six (6) months old and younger are particularly susceptible. Arsenic Arsenic – MCL = 10 ug/L • Source – Arsenic is found naturally in certain geologic formations and is also used in some industries. One common use is a preservative for wood products. • Health Effects – Studies have linked long-term exposure to arsenic in drinking water to cancer of the bladder, lungs, skin, kidney, nasal passages, liver, and prostate. Non-cancer effects of ingesting arsenic include cardiovascular, pulmonary, immunological, neurological, and endocrine effects. Radiological Compounds There are several types of radiological compounds found in drinking water supplies and include; uranium, strontium, total alpha, and total beta. • Source – The primary source of radiological compounds in drinking water is naturally occurring geologic formations. Accidental or intentional releases from human activities is a rare occurrence. • Health Effects – Elevated levels of radiological compounds in drinking water can increase the risk of kidney damage. Lead and Copper Lead and Copper – AL = 15 ug/L for Lead (Pb) and 1,300 ug/L for Copper (Cu) – Lead and copper contamination does not typically occur in the source water or even in the distribution system of drinking water systems. The primary source of lead and copper contamination occurs in internal plumbing systems. Lead and copper are commonly used in the manufacturing of plumbing supplies and can leach out into drinking water. Therefore in 1991, the Lead and Copper Rule (LCR) was passed. The LCR requires water utilities to collect samples for lead and copper within customer homes. While lead and copper is not as common within distribution systems, it is an issue in older communities where lead service laterals and other materials were commonly used. The most recent discovery of lead contamination within a distribution system was in 2014 in Flint, Michigan. As a result, the LCR is going through a number of different revisions. • Health Effects – The primary effects of copper in drinking water are related to gastrointestinal issues. However, the effects of lead in drinking water are far worse and include damage to the brain, red blood cells, and kidney. As previously mentioned, secondary drinking water contaminants are not health related. The problems associated with secondary contaminants can be grouped into three categories: • Aesthetic effects – undesirable tastes or odors • Cosmetics effects – effects which do not damage the body but are still undesirable • Technical effects – damage to water equipment or reduced effectiveness of treatment for other contaminants The periodic table lists the various chemical substances that can be found in water supplies. Below is an image of the periodic table with many of the ions mentioned below circled for reference. Contaminants related to color, odor and taste (aesthetic) include, Chloride (Cl), Copper (Cu), Foaming Agents, Iron (Fe), pH, Sulfate (SO4), Manganese (Mn), Total Dissolved Solids (TDS), and Zinc (Zn). Contaminants related to cosmetic effects include, Silver (Ag) and Fluoride (F). Contaminants related to technical effects include, Chloride, Copper, Corrosivity, Iron, Manganese, pH, and Total Dissolved Solids. Some of the chemical contaminants listed above are compounds or in the case of TDS, are a combination of ions. Sulfate for example is a sulfur ion combined with four (4) oxygen atoms. TDS represents a number of different constituents which include but are not limited to calcium, magnesium, sulfate, chloride, as well as others. Disinfection One of the most critical processes in the area of water quality is the ability to control the growth and regrowth of pathogenic organisms throughout the distribution system. This process is commonly handled through disinfection. By definition, disinfection is the process of cleaning something, especially with a chemical, in order to destroy bacteria. Disinfection should not be confused with other processes such as sanitation or sterilization. Sanitation is the process to make something clean, but it doesn’t necessarily target disease causing organisms and sterilization is the process of ridding something of all bacteria. The goal of drinking water disinfection is to destroy pathogenic organisms in order to make it safe for human consumption. This process is commonly achieved through the use of chlorine and chlorine related compounds or other oxidants. Physical Disinfectants While not common, microorganisms can be inactivated in water supplies through physical means. These include, but are not limited to ultraviolent rays, heat, and ultra-sonic waves. While all of these are physical means of inactivating harmful organisms, they lack something chlorine and chlorine related compounds provide. These processes are good at the time of use but provide no long term protection from regrowth. Non-chlorine Disinfectants Chemicals such as iodine, bromine, various bases (alkaline chemicals), and ozone are good oxidizing agents, but each one has limitations when it comes to drinking water disinfection. Iodine has been used for years to disinfect cuts and skin abrasions and in low doses it can be used to disinfect drinking water. However, because of the high costs and potential physiological effects on pregnant women, it is not used in drinking water. Bromine is commonly used in swimming pools and spas, but because of safety related issues with handling the chemical it is not used in drinking water. An example of a base that can be used as a disinfectant is sodium hydroxide. It is also commonly used to disinfect cuts and skin abrasions, but it leaves a bitter taste if it is ingested and is not suitable for drinking water disinfection. Ozone is a great disinfectant for drinking water under certain instances. It is primarily used in the drinking water treatment process to control taste and odor and to reduce the amount of total organic carbon prior to treatment. The main problem with ozone is it does not leave a residual, is difficult to store, and is expensive. Chlorine and Chlorine Related Compounds Chlorine has been used in the United States to disinfect drinking water for over 100 years. It does a great job at inactivating pathogenic organisms and leaves a residual preventing regrowth throughout the distribution system. In its natural state, chlorine is a gas with a greenish-yellow color. There are other chlorine related compounds such as calcium hypochlorite (solid) and sodium hypochlorite (liquid) commonly used to disinfect drinking water. In addition to chlorine and these related compounds, chlorine is often combined with ammonia to create chloramine. Chloramine is also an efficient disinfectant. One of the major drawbacks to using chlorine as a disinfectant is the potential creation of disinfection by-products such as total tri-halomethanes and halo-acetic acids Distribution System Water Quality As water makes its way through the distribution system, distribution operators need to be able to maintain the quality of the water. Water quality can degrade within a distribution system for a number of reasons, including but not limited to age of water, temperature of water, lack of a disinfectant residual, pH, various reducing agents, and microorganisms. Maintaining a disinfectant residual within distribution systems is an important responsibility for distribution operators. Sampling, monitoring, and various maintenance activities can help with maintaining a disinfectant residual. Distribution Sampling The SDWA states how many and where water quality samples need to be collected. In addition, state regulators such as DDW may also require additional sampling based on vulnerabilities and other water quality related issues. All sources of supply must be sampled routinely for bacteriological, inorganic chemicals, organic chemicals, and radiological contaminants. Each group of contaminants and some individual contaminants have different sampling intervals and procedures. For example, VOCs are required to be sampled at each source annually unless there is a positive detection, in which case they need to be sampled quarterly. Sampling within the distribution system is also required. However, there are far fewer constituents, which need to be sampled in distributions systems. The main contaminants which are required to be sampled for in distribution systems are bacteriological as part of the TCR and disinfection by-products. If you think about this, it makes sense. If you sample source water for VOCs for example, you would not need to sample for VOCs again in the distribution system. The reason for this is because VOCs do not develop in the distribution system. In contrast, in the absence of a disinfectant residual, bacteria can regrow in a distribution system and disinfection by-products may form in a distribution system under certain conditions. As part of the TCR, water utilities prepare sample siting plans. These plans identify the number of customers the utility serves, which in turn determines how many samples must be collected for total coliform bacteria. The sample locations and sampling frequency are also identified in these plans. Larger utilities can be required to sample dozens of locations on a weekly basis for total coliform bacteria as part of the TCR, while smaller utilities may just have to sample a few locations a month. At each location the disinfectant residual is also analyzed. This data can help determine if there is the potential for a problem within the distribution system. Let’s take a look at a hypothetical example. Suppose ten (10) locations per week are being sampled for total coliform bacteria and a chlorine disinfectant residual. Over three weeks, all the total coliform results come back negative (absent of total coliform bacteria), but the sampler has noticed a downward trend in the chlorine residual level at one of the sample locations. This sort of information can indicate a potential problem and maybe the next total coliform sample at this site will come back positive. This scenario doesn’t necessarily mean something is wrong, but the sampler at least has data, which can be presented to other operators and may trigger some type of maintenance. Distribution System Maintenance Maintaining an efficient distribution system can help maintain good water quality. Water entering a distribution system from a source is routinely disinfected with a chemical such as chlorine. While the water travels through the distribution system the disinfectant will do its job by inactivating pathogenic organisms. As this occurs, the amount of chlorine in the system (residual) will reduce. The further the water travels, the lower the residual level. The water also becomes older as it travels through the distribution system and the water can become stagnant, resulting in discoloration, odors, and low chlorine residuals. One way to help keep a disinfectant level at acceptable levels is to help move the water through the system by flushing dead ends and areas furthest away from sources. By flushing and helping to move water through the distribution system, the water and with it the disinfectant residual travels faster through the distribution system and the water does not become stagnant Sometimes, residuals drop very rapidly or cannot be maintained within a distribution system. This typically occurs when the initial dose of the disinfectant is not high enough at the source water, the water stays in the distribution system too long because of low use, or there is some other problem within the distribution system. When this occurs, distribution operators may choose to add a disinfectant in water storage tanks. Since disinfectants are added at the sources of supply they are typically found at higher levels in the distribution system around these sources. Storage tanks are commonly placed on the outer edges of distribution systems and if water demands (usage) are low, disinfectant residuals can drop below acceptable levels. This is when distribution operators can add disinfectants, such as calcium hypochlorite granules or liquid sodium hypochlorite to storage tanks. This will help improve disinfectant residuals within the tank and then in the distribution system as water is taken out of the tanks during times of usage. Water Quality Violations When a water utility does not comply with drinking water quality regulations a violation occurs. Since many states (including California) have their own set of regulations, the states are the primacy agency for enforcing drinking water quality regulations. This means the enforcement comes from the state instead of the USEPA. However, since some regulations are specifically promulgated by the USEPA, they would be the primacy agency for those regulations. Included in the SDWA is something referred to as the Public Notification Rule (PN). This rule ensures consumers will know if there is a problem with their drinking water. These notices are intended to alert customers if there is a risk to public health. Customers are notified when: • The water does not meet drinking water standards; • If the system fails to test its water; • If the system has been granted a variance (use of less costly technology); or • If the system has been granted an exemption (more time to comply with a new regulation). If a water utility cannot meet a drinking water standard, that is they exceed an MCL for a contaminant, in addition to notifying their customers, several things are commonly triggered: • Resampling the water must occur. Depending on the contaminant, several resamples may be required. • If these results confirm an MCL has been exceeded, then the source is usually taken out of service. There are some exceptions. Depending on the health effect, the primacy agency may allow the source to be blended in order to bring the level of the contaminant below the MCL. • Depending on the health effect of the contaminant, the utility may be required to notify the public immediately. Other times if the health risk is minimal, the utility would be required to notify their customers in an annual consumer confidence report. • Depending on the level and the health effect of the contaminant, the utility may be required to install some form of treatment in order to remove or lower the level of the contaminant With some contaminants where a positive result occurs, but the level is below an MCL, additional monitoring is sometimes required. For example, nitrate has one of the more complex additional sampling requirements. Nitrate Sampling Requirements The SDWA states that nitrate must be sampled annually at each source entering the distribution system. If the result is more than half the MCL (>22.5 mg/L as NO3 or >5 mg/L as N) then quarterly sampling is required. Quarterly must continue until four (4) consecutive quarters yield results less than half the MCL. Consumer Confidence Report (CCR) The CCR is an annual report sent to all customers receiving water from a utility. This report provides information on the sources of supply, updates on new or emerging water quality regulations, health effects from contaminants found in their drinking water, levels for all contaminants found in the drinking water supply, and any violations which may have occurred. This CCR is very helpful in communicating to the public the safety of their water supply. The information within the report is from the prior calendar year and must be sent to all customers by July 1 of the following year. The report also must be provided in each language spoken within the utility service area if the population speaking that language is greater than ten (10%) percent of the total population. Sample Questions 1. CCR stands for ___________ and is provided to ___________. 1. Consumer Confidence Regulations/all water utilities 2. Customer Certification Requirements/all customers 3. Consumer Confidence Report/only select customers 4. Consumer Confidence Report/all customers 2. Stagnant water in a distribution system can have the following qualities ___________. 1. Discoloration 2. Odor 3. Low chlorine residual 4. All of the above 3. Tri-halomethane are considered ___________. 1. Surface water contaminants 2. By-products of the disinfection process 3. Groundwater contaminants 4. All of the above 4. AWWA stands for ___________. 1. American Water Workers Agency 2. American Water Wage Association 3. American Water Works Association 4. None of the above 5. Primary drinking water standards are considered ___________. 1. Health-related 2. Aesthetic-related 3. Not enforceable 4. Less important than secondary standards

textbooks/workforce/Water_Systems_Technology/Water_140%3A_Water_Distribution_Operator_I_(Alvord)/1.03%3A_Regulations.txt

Student Learning Outcomes After reading this chapter, you should be able to: • Explain how source water availability and reliability affects distribution system design • Describe the three main distribution system configurations • Evaluate the main requirements, which affect the quantity of distribution system storage • Analyze and describe the main types of distribution system maps When designing a water distribution system a lot of different things need to be considered. For example, the following questions are some which might be considered: • What will the water be used for? • Is it a small rural farming community or a large industrial metropolitan city? • Will the community grow in size? • Are there other sources of supply available? Planning is an important step in the design of a water distribution system. Most early communities were built around a water source, some place where water was available. This obviously made planning and design much easier. However, as villages grew into towns and as communities began to spread out well beyond the original sources of supply, planning and design became more difficult and more important. Below is a list of a few things that should be considered prior to or during the design of distribution systems. 1. Water availability – Is there an available supply of water to meet current and future demands? 2. Source reliability – How reliable is the source or sources of supplies? 3. Water quality – Does the current water quality meet regulatory standards? 4. Location – What is the location of the community in relation to the sources of supply? What is the topography of the community? 5. Local, state, and federal requirements – In addition to water quality regulations, there are other local, state, and federal regulations Let’s break down each one of these items in a little more detail. Water Availability It is not by coincidence that early settlers and homesteads were in close proximity to rivers and lakes. These water bodies provided a source of freshwater for drinking and bathing. In addition, it provided a good source of food. In addition to fish, other animals would gather around water sources. As communities began to grow, the availability of water became more and more important. In the late 1800s and early 1900s, Los Angeles relied mostly on local groundwater supplies. However, as the population began expanding rapidly, the need for another source of supply became evident. At the time, William Mulholland was the Los Angeles Water Company Superintendent and was instrumental in bringing water from the Owens Valley area in the north, making it available so Los Angeles could continue to expand. Bringing water from the north to southern California required an extensive transmission pipeline system. Once the water reached Los Angeles, a distribution system network allowed people to reside and spread out all across the area. A water transmission system is typically composed of large diameter pipelines bringing water to areas, which lack available water supplies. In contrast, a water distribution system disperses water throughout a given area through smaller diameter pipelines. Pipeline diameters and types will be discussed in more detail later in this text. Water Reliability Accessing water from different sources and locations, such as in the case of Los Angeles, allowed for cities to grow at a rapid rate. In the early 1900s, William Mulholland realized the local groundwater serving the city of Los Angeles would not sustain the growing population and discovered another source of supply to the north. In this case, the Owens Valley not only provided an additional supply (availability) for Los Angeles, it also increased the supply reliability for the region. Multiple supplies of water increase reliability. For example, if an area relies on a surface water supply as their main source and there is not enough precipitation one year to sustain the surface supply, a local groundwater system can supplement the demand. In a distribution system having pipelines, which interconnect, can provide a more reliable supply in the event of pipeline breaks or system failures. For example, a grid pipeline network (discussed later in this chapter) provides water service from multiple directions allowing water to be served to customers from more than one location. Having a reliable supply of water and a redundant system of pipelines is critical to an efficiently run water distribution system. In addition, having back up sources of power to operate pumps in the event of power outages also provides increased reliability. Water Quality In addition to having an available and reliable supply of water, it is important to have a supply, which meets water quality standards. A safe water supply is equally as important as any other consideration when designing a water distribution system. In instances where source water quality does not meet drinking water regulations, treatment can be implemented. However, if sources of supply are not in centralized locations, the cost of treatment can be prohibitive. For example, if a water utility has multiple drinking water groundwater wells and these wells are spread throughout the distribution system or several miles, centralized treatment would be difficult. If each of these wells were contaminated, it might mean individual treatment systems would need to be installed at each location. The cost for individual treatment systems is typically more costly than a centralized treatment system. In contrast, if these wells are located within close proximity to each other, a centralized treatment system could be installed. This could significantly reduce the cost of treatment. The cost of treatment is paid for by each customer through water rates. Therefore, in smaller communities, any type of treatment could be costly causing devastating consequences for the residents. This is purely an “economy of scale” issue. For example, if the Los Angeles Department of Water and Power (LADWP) had to provide treatment on a groundwater well, the cost of this treatment would be spread out among their rate base (total number of paying customers). LADWP has hundreds of thousands of paying customers. However, if a small rural water utility with only a few hundred or even thousand customers needed the same type of treatment, it might end up being cost-prohibitive. Location The next area which needs to be considered is location. When it comes to real estate, the common mantra is “location, location, location”. Well, this sort of speaks true to a water distribution system too. Location provides for water availability, reliability, and quality. This is not to say water cannot be brought in to areas where it does not naturally exist, but it does come at an additional cost. Water that is of good quality, readily available, and reliable will be considerably cheaper than if clean and reliable water needs to be imported over long distances. Location also has to be considered when it comes to the actual design of a water system. For example, is the water distribution going to be built in an area, which is subject to freezing temperatures? If so, this will affect the depth of water distribution system infrastructure as well as above-ground appurtenances such as fire hydrants. If a fire hydrant is filled with water and the ambient temperature is below freezing for long periods of time, the water within the hydrant can freeze rendering the hydrant inoperable. Topography will also affect system design. Are there wide ranges of elevation of the proposed water distribution system or is the topography relatively flat and uniform? If there is a wide variation in elevations, additional pumping might be required, as well as other appurtenances compared to an area where the terrain is flat. Other things that may affect distribution system design based on location are things like soil corrosivity and local geology. This can affect the types of material used for things such as piping as well as the installation process. Local, State, and Federal Requirements Regulations will dictate minimum water quality and some system design standards and details. These standards and details can range from permitting the installation of facilities to very specific drinking water quality regulations. Each state, county, and city can have different criteria that can affect the design and installation of a water distribution system. At a minimum, all public water utilities must meet federal drinking water quality regulations. These regulations however, can vary from state to state. State drinking water quality regulations must be at least as strict as the federal standards, but they can be more stringent. An example of this is with the constituent chromium. There are several valance levels of chromium, with chromium VI being the most common. However, the federal Safe Drinking Water Act (SDWA) and California (SDWA) have a maximum contaminant level (MCL) for “total” chromium. This is the maximum level of all valances of chromium allowed in drinking water. In the federal SDWA, the MCL for total chromium is 100 micrograms per liter (ug/L) and in California, the level is 50 ug/L. This is an example where the state water quality regulation is more stringent than the federal requirement. When it comes to design and installation criteria, there can be a number of local requirements, which include excavation permits, offset distances from other facilities, as well as other conditions. It is important for the design team to understand these requirements and help plan for them before and during the installation of distribution facilities. In addition to these considerations when it comes to the design of a distribution system, there are a variety of other criteria that should be considered. Below is not an exhaustive list, but it covers various items that should also be considered. • Future growth – In many areas, there are or will be plans for future growth. Some of these growth projections are understood through local planning documents, while other areas might not have as much detail. Regardless, it is always prudent to work with local agencies on the potential for future development plans and growth. This is particularly important when it comes to the sizing of facilities. For example, if a pipeline for an existing number of homes only needs to be six (6) inches in diameter, but will need to supply many more homes in the future, it might be prudent to increase the size of the pipeline in anticipation of this future growth. This is also true for pumping and storage facilities. It is important for water utilities to understand the projected population growth of their area, understand the existing and future projected water demands, and what sort of fire protection requirements are needed for each type of customer class. • Cost and Funding – Cost is another important item to consider when designing and building a new or expanding an existing distribution system. Who benefits from the work being done? Is the distribution system expansion for a new development or is it to improve the service for existing customers. Many times if a new development is being planned, the owner (developer) of the property will be responsible for paying the costs associated with expanding the distribution system. However, the developer should also be responsible for paying some portion of the cost for the existing water system too. Why you might ask? Well, while the existing water system is benefitting the existing customers, a portion of the existing system will provide some benefit to the new development as well. Understanding this proportional cost is beyond the scope of this chapter and would be covered in more detail in a text related to water rates. However, it is important to understand that building a new distribution system or expanding an existing distribution system is quite costly and this cost needs to be shared by the customers receiving benefit. Sometimes a developer will pay for some or all of a distribution system project while other times the utility may carry debt to fund certain projects and then spread the cost to their customers over time. Distribution System Layout Planning is an important step in designing the layout of a water distribution system. While all the items discussed above should be considered before and during the planning stages, there are other “nuts and bolts” related planning items in order to layout the design of a distribution system. Distribution systems are commonly designed by the utilities engineering department while other times engineering consultants are used. Regardless of who the engineer is, planning the design layout is a critical step in any distribution system. Calculations need to be completed in order to properly size facilities, pipelines, and the various appurtenances of a distribution system. Some of the items which are considered are the following: • Water demands • Flow rates • Flow velocity • Fire flow requirements • Topography • Pressure • Power requirements • Material selection • Land ownership This is by no means an exhaustive list. However, it should provide some insight into things, which are considered when planning and designing a distribution system. These and other items help determine what materials are selected, the size of facilities needed, and how things are designed and ultimately installed. While most of the planning and design of distribution systems is conducted in the office with professional engineers, distribution operators should also be consulted. Unfortunately, this step of discussing the planning and design of a distribution system with field operators is sometimes overlooked. Many times, the steps of planning and design happen without the input from the very people who will be installing and operating the systems being designed. It might seem obvious to consult distribution operators, but why then is it often overlooked? A lot of information is gathered during the planning and design phase. One of the more important things to review are plans called as-built drawings. An as-built drawing is simply that, it is a plan that is modified after it was installed and “as it was built”. Even after everything is considered during the planning and design stage, when the design plans make it to the field and the facilities are actually installed, things are often adjusted and changed during installation. These changes and adjustments are the result of conflicts that were not identified on the design plans and can end up costing significantly more than what was initially proposed. While the idea of being able to avoid all conflicts is not conceivable, consulting with field employees before the design plans are complete can help reduce some of these unforeseen conflicts. Distribution Design Configurations One of the more important things behind the functionality of a distribution system is the layout or configuration. There are three (3) common distribution system configurations. These are arterial loop, gird, and tree systems. Each one will be explained below. While some of these may be a more preferred and ideal installation configuration, sometimes less desirable designs cannot be avoided. The primary goal of a well-designed water distribution system is to provide good water quality at acceptable pressures to the utility’s customers. In order to meet these and other objectives such as meeting the required customer water demands, which include flows to fight fires and limiting the number of customers out of water during outages, the design of a water distribution system is extremely important. Arterial Loop System The idea behind an arterial loop system is to provide flexibility by supplying water to the distribution system from multiple locations. This system attempts to surround the distribution system with larger diameter water mains. This provides adequate flows (volumes of water) to the interconnecting distribution system from different locations. Arterial mains are constructed on the perimeter of a distribution system bringing a main flow of water supply from various branches. An arterial loop system typically has very large diameter pipes (referred to as transmission mains) providing water to smaller but still large diameter mains (referred to as arterial mains), which then feed water to smaller mains (referred to as distribution mains), and finally, these mains distribute water to the customers. See the example diagram below. Grid System A grid system is one of the more desirable distribution system layouts. They can provide water to all customers from multiple areas. This configuration allows water to circulate throughout the entire system providing better water quality, pressures, and flow rates. Another positive benefit to a grid system is the ability to limit the number of customers who are out of water during outages from things such as water main breaks. The main difference between an arterial loop and a simple grid system is the grid system shown below is typically fed by a single transmission and/or arterial main. Tree System This type of distribution system is the least desirable design. A tree system is typically fed by one larger main and then branches off to smaller distribution mains. However, as shown below, a tree system’s distribution mains end in something referred to as “dead ends”. Dead ends are where a water main terminates at the end of a cul-de-sac or other area where it cannot connect to another distribution main. Dead ends can result in reduced water quality, pressure, and flow. If a dead end distribution main is too large, the water in the main can become stagnant and cause undesirable taste, odor, and color water quality problems. Therefore, dead-end water mains are sometimes undersized and then can result in reduced pressures and flows. Appurtenances An appurtenance is a generic term for accessories associated with a functioning distribution system. In this chapter, we will only focus on the last two appurtenances in the list below. Most of the others on the list below will be discussed in more detail later in this text. • Valves • Fire hydrants • Elbow and angles • Fittings • Blow offs • Air and vacuum valves (airvac) In water distribution systems where there are high and low points (topographic elevation changes) blow offs and airvacs are commonly used. When you have low points in water pipelines, debris (sand, dirt) can accumulate at the bottom of the pipes. Also, as previously mentioned, water can become stagnant at the end of pipelines (dead ends). In these situations, blows are installed. Blow offs allow distribution system operators to flush water in order to remove any stagnant water or debris. In contrast, air can accumulate in high points of a pipeline. In order to remove air, air and vacuum valves are installed to automatically release air from the distribution system. Below are some examples of these appurtenances. Water System Demands As mentioned previously in this chapter, water demand is an important parameter, which is reviewed when planning and designing a water distribution system. Water demand includes a number of things including the demand of all customers within a distribution system (residential, commercial, industrial) and the demand to fight fires. It is important to identify not just the average demand of a distribution system, but also the maximum amount of water demanded on any given day and the peak demand during any given hour of the day. These three (3) demand factors are critical in the design of a distribution system and are defined below. • Average Day Demand (ADD) – The average day demand is the total distribution system water use over one (1) year, which is then divided by 365 days. In the design of a new distribution system without any existing users, land use projections are commonly used to estimate the amount of water, which will be used by future users. • Maximum Day Demand (MDD) – The maximum day demand is determined by looking at the entire demand over one (1) year and determining the day with the highest (maximum) usage over one twenty-four (24) hour period. Daily demands are typically calculated using production meters from supply facilities bringing water into a distribution system. • Peak Hour Demand (PHD) – The peak hour demand is the highest water usage over a one (1) hour period. This demand number can be measured by production meters, but can also be estimated through calculations. Fire Flow Demands Residential, commercial, and industrial water demands are important for designing a distribution system. However, fire flows are a critical component, especially when sizing storage and pumping facilities. Fire flows are commonly the determining factor when sizing water systems in smaller communities serving a population of less than 50,000 people. Fire flows are determined through a variety of fire and building code criteria determined by the Insurance Services Office (ISO). Local fire departments and organizations are typically responsible for providing this information and guidance to water utilities. Among other criteria, the ISO identifies minimum pipe diameters for specific uses, as well as pressure and flow requirements. Most areas have a requirement that pressures do not drop below twenty (20) pounds per square inch (psi). The flow requirements will vary based on the type of use, such as schools, commercial buildings, and residential areas. Network Analysis Engineers use a variety of tools when planning and designing a water system to determine the size of facilities, which will dictate the pressure, and velocity of the water flowing through the pipes. The pressure within a distribution system is determined primarily by the elevation of the storage facilities within the system. Pressure is commonly measured in pounds per square inch (psi). One (1) pound per square inch equates to 2.31 feet of elevation, referred to as “head pressure”. Therefore, if a water storage tank sits one hundred (100) feet above a water service, the subsequent pressure would be 43.3 psi. Mathematically, this is accomplished by dividing 100 feet by 2.31 (see below). • 100 Feet x 1 psi2.31 feet=43.3psi This pressure is a theoretical pressure in a water distribution system. As the water moves through pipes and the various appurtenances throughout a distribution system, the pressure is reduced due to friction. The roughness of the interior of the pipe, the diameter of the pipe, the changes in direction of the piping, and valves, all have an effect on the velocity and pressure of the flow of water. A standard calculation used by engineers to determine this head loss due to friction is the Hazen-Williams equation. Another commonly used formula is the Darcy-Weisbach equation. These equations are beyond the scope of this text and beyond the necessary knowledge for distribution system operators to perform their jobs appropriately. Therefore, they are discussed in this chapter, but will not be used or explained beyond the general nature of their use by engineers. Since the Hazen-Williams equation is ideal for fluids such as water flowing at ordinary temperatures (40°to 75°F) it is the more commonly used formula. This equation is used to identify the smoothness (roughness) of the interior of a water main. The rougher the pipe interior, the more friction loss will be observed. This equation relates the flow of water in a pipe with the physical properties of the pipe and the pressure drop caused by friction. The resulting value is referred to as the C-Factor. The higher the C-Factor the smoother the pipe interior and the less head loss from friction. The lower the C-Factor, the rougher the pipe interior, which results in greater head loss from friction. The table below shows some typical pipe materials and corresponding C-Factors. Material Hazen-Williams C-Factor Asbestos Cement 140 Cast-Iron 20 years old 89-100 Cast-Iron 40 years old 64-83 Steel 140-150 Ductile Iron (cement-lined) 120 Ductile Iron 140 PVC (C900/905) 150 Another tool engineers use to determine the various parameters of a water distribution system is a hydraulic water model. Water models can help determine expected flows and pressures throughout a distribution system network and can sometimes accurately mirror what is occurring in the distribution system. While these models can be accurate in predicting pressures and flows, it is also helpful to calibrate these computer models with actual field data. Pressure recorders can be placed throughout a distribution system on things such as fire hydrants to measure and record the pressure in a distribution system over a period of time. Some pumping equipment can also be equipped with devices to measure the pressure on the suction and discharge side of a pump. Pressure is an important parameter to measure and monitor within a distribution system. Some systems can have excessive water pressures or very low pressures. This presents a problem for utility operators and customers alike. If pressures are too low, customers may not be able to operate things like irrigation sprinkler systems. If pressures are too high, things may prematurely fail due to the excessive pressure. Under normal flow conditions, acceptable pressures are commonly within the range of forty (40) psi to one hundred fifty (150) psi. However, at times certain areas within a distribution system, pressures can exceed even these relatively high values or drop below acceptable levels. Therefore, understanding what the pressures are going to be will dictate what types of materials (especially pipes) are acceptable. Pipeline strength is commonly expressed in terms of tensile and flexural strength. In addition to the internal loads expressed on pipes, there are also external loads such as traffic driving over pipes buried below ground or the amount pipe can bend or flex. • Tensile Strength – This is the measure of the resistance a pipe has to the longitudinal or lengthwise pull it has before it will fail. When the flow of water changes direction within a distribution system network, it can put these types of forces against the pipe. Therefore the material chosen can be critical. • Flexural Strength – This characteristic is the ability of a pipe to bend or flex without breaking. If the trench bedding (dirt) is not flat or if the pipe being installed needs to bend slightly as the road meanders left or right, different pipe materials have different abilities to bend or flex. If a pipe does not have the adequate strength, then the possibility of a water pipe (main) break can occur. If the earth shifts during an earthquake for example, a pipe may rupture in what is referred to as a shear break. If a buried pipe is unevenly supported, a beam break may occur. In addition, if the internal pressures exceed the acceptable operating pressure of a pipeline, it may also rupture. Therefore, understanding the pressures within a distribution system and the appropriate materials to use under different circumstances is an important aspect of planning and design. Mapping (Plans) Once all the planning is finished and the design criteria is selected, engineers get to work on creating design drawings (or plans) for the construction crews to use during the installation (construction) phase. These “construction plans” and accompanying specifications are not only important for the crews to properly build and install the distribution system facilities, but they are also used in the budgeting (estimating) process. Once a set of plans is complete, contractors can provide bids or cost estimates. The estimates will include the cost for materials, labor, and equipment needed for construction. There are various types of plans for a distribution system. These typically include piping plans, pump station plans, source of supply plans (i.e., groundwater wells), and storage facility plans (above ground storage tanks). Each set of plans will have the pertinent information for constructing and the material needed. For example, a set of pump station plans will have all the required mechanical and electrical equipment needed. These plans will detail the facility housing this equipment. The facility might be as simple as a chain-linked fence or as elaborate as a block walled building with a roof. Specifications will be detailed enough so the contractor performing the work will know what pumping equipment, valves, piping, motors, and any other items required to construct a full functioning pump station. After facilities are constructed, plans are updated to reflect any changes that have occurred during the construction process. Even on the most thoroughly prepared design plans, things often change when they are actually constructed. Therefore, it is the responsibility of the construction contractor to make up the plans for the engineer to modify and update. These updated plans are referred to as as-built drawings. Once the as-built drawings have been prepared, they need to be provided to the distribution operators for future reference. These maps give the distribution operators information regarding all the existing facilities for locating and operating purposes. Each water utility will have its own standards and mapping styles, but typically, there are three (3) main types of maps. These are comprehensive, sectional, and valve and hydrant maps. • Comprehensive Maps outline the entire distribution system. They are useful in understanding the various pressure zones, general locations of pipelines and larger facilities, and commonly outline the entire service area boundary of the utility. • Sectional Maps provide a more detailed picture of the distribution system on a larger scale. While these maps are similar to comprehensive maps, they have more details. For example, sectional maps will show distances between water main pipes and other buried utilities such as sewer and storm drain pipes. These maps help distribution operators identify which side of the street pipelines are located and provide the size and material as well. • Valve and Hydrant Maps show the precise location of distribution system valves and fire hydrants. This information is extremely important so distribution operators can quickly identify which valves need to be isolated (closed) when there is a water main break. These maps are commonly used by distribution operators for valve and hydrant maintenance activities. Many times the local fire department will request copies of these maps so they have a clearer understanding of fire hydrant locations. The designing of a water distribution system is an important process in order for a water utility to be able to provide their customers with a reliable and high-quality supply of water. Multiple departments are typically involved as well as outside consultants in order to properly plan, design, and construct a distribution system, which complies with all the required laws and regulations and operates in an efficient and functional manner. Sample Questions 1. Which of the following is the most desirable system configuration? 1. Arterial loop 2. Tree 3. Grid 4. Depends on the system 2. Dead-ends cause ___________. 1. Restricted flow 2. Stagnant water 3. Water outages during breaks 4. All of the above 3. Blow offs should be installed ___________. 1. At high points 2. Low points 3. Regular intervals 4. Only on large main lines 4. Air and vacuum valves should be installed ___________. 1. At high points 2. Low points 3. Regular intervals 4. Only on large main lines 5. ISO stands for ___________. 1. Insurance Services Organization 2. Insurance Services Office 3. Insurance Standards Organization 4. Insurance Standards Office

textbooks/workforce/Water_Systems_Technology/Water_140%3A_Water_Distribution_Operator_I_(Alvord)/1.04%3A_System_Design.txt

Student Learning Outcomes After reading this chapter, you should be able to: • Describe the different pipe materials and sizes • Explain hydraulics and how water moves through pipes • Identify the causes and results from water hammer and tuberculation Throughout the history of water distribution, a critical component of getting water from the source to the customer is pipelines. Pipelines within a distribution system can be separated into three (3) main categories: • Transmission Piping • Distribution Piping • Service Piping These three (3) categories have very distinct characteristics and uses. Transmission Piping Transmission water mains (piping) are the largest in diameter of the three. They can range from as small as 16” in diameter up to more than 120” in diameter depending on the size of the distribution system, the location of the source water, and the number of customers within the distribution system service area. Smaller utilities with the sources of supply relatively close to the distribution system would have the smaller diameter pipes while larger utilities with the source water further from the distribution system would have larger diameter transmission mains. Transmission water mains convey large volumes of water from the source to areas within the main distribution system. They are commonly installed without any other connections to the pipe until it reaches the distribution system. However, in smaller distribution systems there can be additional pipes connected to a transmission main and there may even be service connections. Below is an example of a transmission water main. Distribution Piping Distribution system piping is simply that, piping that distributes water throughout the distribution system. Diameters of distribution system piping range from as small as 4” up to 24” and sometimes larger. The most common sizes of distribution system water mains are 8” – 12”. Distribution mains connect to transmission mains as these pipes enter a distribution system. These water mains branch off into roads within communities to bring water supplies to customers. Service Main In order to get water from the distribution main to a customer, a service main (lateral) is attached to the distribution main. In the diagram above, you can see this pipe between the distribution main and a black dot. The black dot represents the water meter or point of connection between the water utilities infrastructure and the customer’s piping. Service laterals typically range in size from 1” to 10” in diameter. Most single-family residential service laterals are 1” to 2” in diameter, while larger commercial services can range in size up to 10” in diameter and sometimes even larger. The size of a service lateral is dependent on the amount of water use from the customer. Pipe Selection There are a number of things, which dictate the type of pipe material a utility would select. As discussed above, the use is something utilities look at to determine the material to use. Other things include resistance to corrosion, interior smoothness, cost, ease of use, strength, and local conditions (i.e., soil type). Pipeline Materials There are various materials used for water mains. In the 1800s up to the early 1900s, wooden water mains were used. Wood was a usable material because hollowed-out wooden logs did not expand like metal pipes and the thickness provided insulation properties. However, as distribution systems became more sophisticated and pressures increased, wooden pipes were replaced with grey cast-iron pipes. Grey cast-iron pipe (CIP) was easier to manufacture. They were strong and provided a long service life. One of the main drawbacks of this pipe was its brittleness. If the pipe wasn’t handled carefully, it would easily crack. Another major drawback was the lead poured joints. In order to properly connect sections of the pipe together a molten lead joint was poured around each connection point. Ductile Iron Pipe In the early 1970s, manufacturing plants moved away from CIP and started manufacturing ductile-iron pipe (DIP). DIP is even stronger than CIP, more versatile, not brittle, and does not use any lead. The only drawback to DIP is the susceptibility to corrosion from aggressive waters and soil. In order to protect the inside of DIP from corroding, they are commonly lined with cement mortar. If soils are corrosive, DIP is usually wrapped in plastic bags. The images below show examples of cement mortar lined (CML) DIP and DIP that has been “bagged” before installation. DIP typically comes in diameters of 4” – 64” and usually in lengths of 18’ – 20’. The pressure range for DIP is 150 psi to 350 psi. Steel Pipe Steel pipe has been used for well over a century. In the mid-1800s when water pressures were high, steel pipe was commonly manufactured for use. While steel pipe can be manufactured to small diameters (4”), the more common use of steel pipe is when large diameters are needed. Diameters of steel pipe ranges up to 120” and even larger if needed. Steel pipe is lighter in weight than CIP and DIP and can be fabricated for special needs. Some of the main disadvantages to steel pipe are both internal and external corrosion and the potential for a partial vacuum to collapse the pipe. Asbestos-Cement Pipe Asbestos-Cement Pipe (ACP) was first introduced in the US around 1930. It was commonly used in areas where metallic pipe was subject to corrosion. Pressure classes are not typically as high as pipe made from metal, but they come in pressure ranges up to 200 psi. ACP only comes in diameters ranging from 4” to 42” and the lengths (10’ – 13’) are shorter than their DIP counterpart. ACP is not subjected to aggressive waters as metal pipe, it is fairly lightweight and has a relatively smooth interior surface. It is fairly brittle and can crack if not properly handled. Special safety precautions must be taken in order to prevent employees from being exposed to asbestos fibers. Polyvinyl Chloride Pipe Polyvinyl chloride pipe (PVC) were first introduced around 1940. The durability, resistance to corrosion, lightweight, and cost-effectiveness soon became very attractive in the waterworks industry. Because these pipes are made with vinyl chloride, they must be tested and meet certain criteria to ensure no harmful chemicals leach out. In some instances, PVC pipe can also cause taste and odor problems. Another desirable characteristic of PVC piping is flexibility. When using PVC piping, special care must be taken when storing for long periods of time since plastic is susceptible and can become damaged from ultra-violet light. The above-mentioned pipes are primarily used for transmission and distribution piping. The material used for service laterals are commonly made of either copper or PVC. However, in years past, galvanized pipes were also used. Copper is malleable and resistant to corrosion, which makes it a perfect material for piping between a distribution main and the point of connection to a customer. PVC is also used with the preferred type of PVC being polybutylene since it is not as ridged as schedule 40 or schedule 80. Pipeline Connections Water mains are generally connected together with either mechanical or push-on joints and sometimes flanged connections. The type of connection is determined by the installation. For example, above-ground pipeline installations, such as in pump stations, flanged connections are very common. A flanged connection provides a strong and ridged connection and allows for easy disassembly if a section of pipe or other appurtenance needs to be removed. Flanged connections are not as common in underground installations, primarily because of the exposed nuts and bolts of flanged fittings. Pipes connected with push-on joints are manufactured in a “bell” and “spigot” style. The bell end is a wider flared end and the spigot is narrower and tapered. See the example below. The bell end has a gasket inside and the spigot end is “pushed” on to make the connection. Both ends of the pipe must be thoroughly cleaned and lubricated before making the connection. One of the main problems with push-on joints is the possibility of the joints separating under certain conditions. In addition, on slopes, push on joints must be installed with the bell end facing uphill. This will prevent the spigot end from sliding out of the bell. In some instances where additional support is needed, there are certain restraints that can be used. These types of connections are typically less expensive than other connections and are easier to install. Mechanical joints, restrained joints, and flanged connections are also used to connect pipes and fittings together. Flanged connections are typically limited to above-ground installations because of the potential of corrosion and dirt filling in around the bolts. Mechanical joints are similar to push-on joints. However, they have a means to “lock” the pipe and fittings together. Restrained joints are used with push-on fittings and require some type of restraining system. Below is an example of one such restraining system, mega lug rods. Tie rods are another type of restraining system. These help to hold two sticks of pipe together. Sample Questions 1. Flanged pipeline connections are very common ___________. 1. In below-ground installations 2. Only for sewer systems 3. In above-ground installations 4. None of the above 2. Asbestos-cement pipe come in lengths ___________. 1. Longer than DIP 2. Shorter than DIP 3. The same as DIP 4. All of the above 3. Transmission water mains deliver ___________. 1. Water directly to customers 2. Water to treatment plants 3. Carry large amounts of water 4. Water directly from service laterals 4. Which of the following would be a correct order for how water gets to a customer? 1. Source, distribution main, transmission main, service lateral 2. Service lateral, distribution main, transmission main, source 3. Source, transmission main, service lateral, distribution main 4. Source, transmission main, distribution main, service lateral 5. Which of the following pipe material is most susceptible to collapse from partial vacuum? 1. Steel 2. DIP 3. Plastic 4. Concrete

textbooks/workforce/Water_Systems_Technology/Water_140%3A_Water_Distribution_Operator_I_(Alvord)/1.05%3A_Pipelines.txt

In this chapter, we will examine water distribution valves and why they are used. Student Learning Outcomes After reading this chapter, you should be able to: • Describe the different types of valves • Explain why different valves are used with different applications • Identify the operational and maintenance criteria for valves Water valves are an important part to any water system. The main purpose of a valve is to stop and isolate the flow of water. There are many different types of valves and the uses vary, but the primary purpose is to stop the flow of water. However, as you will see in this chapter, valves serve a variety of purposes. Valves are used to stop and start the flow of water. When a pipe breaks, in order to stop the flow of water a valve is commonly closed. This prevents the water from flowing and allows for utility operators to repair the pipe. Once the repair is finished, the valve is opened and water is allowed to flow once again. Some valves are used to regulate pressure or throttle flow. Sometimes the water pressure is too great and can pose a problem and damage pipes or other equipment. Residential homes commonly use pressure regulating valves in order to reduce the pressure before the water enters a home. These types of valves can also be used within a utilities distribution system. Throttling flow is sometimes needed in order to reduce the amount of water passing through pipes. Certain valves are used to allow the flow of water in one direction only. These valves prevent the flow of water in the opposite direction. A common type of valve is a check or backflow preventer. These valves are unidirectional valves and allow the water to flow in one direction only. Other valves are designed to relieve pressure. When water pressure builds up and gets to a point where the pipes or other appurtenances can get damage, a pressure relief valve can be used to allow the water to flow out of the system and relieve the high pressure. Types of Valves There are a number of different types of valves in the water industry for the various uses described above. The following list of valves is not an exhaustive list, but it is a very comprehensive list of valves used in the water industry: • Gate • Globe • Pinch • Diaphragm • Needle • Plug • Ball • Butterfly • Check • Relief • Control Each one of these valves has specific uses and some of these valves are more commonly used than others. Understanding the various uses and types of valves is important for understanding how water distribution systems function. For example, there are several types of valves commonly used in water mains in order to stop the flow of water. However, a certain type (butterfly) is not suitable for a maintenance function referred to as “pigging”. Pigging is a process to clean the inside of a water main. “Pigs” are made from various materials, but are commonly made of foam of various densities and are pushed through a water main. If a water utility uses butterfly valves then this type of cleaning process is not possible because the valve would be an obstruction. Other types of valves can be used at pump stations, wells, or other locations within a water distribution system. Each valve will be discussed in detail throughout this text. However, it is important to understand the four (4) principle uses of valves within a distribution system. • Starting and Stopping Flow – In order to change the direction of the flow of water, stop the flow of water, and then start the flow of water, certain valves are used. When a water pipe breaks, a valve is used in order to stop the flow of water and isolate the leak so it can be repaired. Once the repair is made, the valve will be opened in order to start the flow of water once again. Some examples of these valves in a distribution system are distribution system isolation valves, fire hydrant auxiliary valves, pump control valves, and water service valves. • Regulate Pressure and Throttle Flow – Certain valves are used to lower the pressure if it is too high or to reduce the flow of water by throttling the flow. Only specific valves should be used for these purposes because some valves can get damaged if used for the incorrect purpose. An example of a pressure regulating valves within a distribution system is one installed between two different pressure zones. One zone is higher than the other and these types of valves can be installed to reduce the higher pressure and release water when needed to the lower pressure area. • Prevent Backflow – To prevent water from flowing in the wrong direction certain valves can be used to prevent something referred to as backflow. Backflow prevention is needed when a potable water supply is connected to a non-potable water supply. There are five (5) main methods and devices used for preventing backflow. These will be discussed later in this chapter. • Relieve Pressure – When pressure is too high within a water system, sometimes the pressure needs to be relieved in order to prevent a rupture of the system. Pressure relief valves are common in various installations. Air and vacuum valves are an example of a pressure relief valve within a distribution system. These valves allow air to escape preventing sudden rupture of a pipe. What Differentiates the Various Types of Valves? Valves can be classified by how they regulate the flow of water. There are four (4) main types of how a valve operates: • Closing Down – Globe and Piston valves close down in order to stop the flow of water A globe valve is commonly found on outside residential faucets, also referred to as a sill cock. The “plug” end of a globe valve closes down into a valve port, which shuts off the flow of water. The distance between fully open and fully closed is relatively short. A piston valve is similar to a globe valve. It is equipped with a piston shaped closure member, which intrudes into a seat bore to stop the flow of water. Piston valves are commonly used on control valves. These types of valves are susceptible to sediment being trapped on the seat preventing the valve to close down completely. There is also some amount of flow resistance with these types of valves, especially a piston valve. • Sliding – Gate valves are the most common valve found in distribution systems. They are classified as a sliding down style. A handwheel or a key lowers a “gate” down on a seat. The face of the gate can become worn or objects can get lodged under the gate preventing a tight or complete seal. These types of valves should not be used to throttle flows as the gate can become damaged from the force of the flow of water. There are several different types of gate valves and they will be discussed later in this chapter. The image below is an above-ground type of gate valve with a handwheel attached to the operating nut for opening and closing. • Rotating – The various types of rotating valves include, plug, ball, butterfly, and cone. These types of valves rotate to open and close. Some, for example, plug and ball valves, are rotary style rotating valves. This means they are quarter or half turn rotary valves. While others like butterfly valves rotate on a shaft to open and close. In the diagram above, the lever of a ball valve is turned one-quarter of the way and the ball that is blocking the flow opens to allow water to flow through. The “ball” that is in the line of flow is solid on each side and is open on the other sides. The rotating cylinder on these valves can also be cone-shaped. Smaller plug valves are used on customer service lines. The valve that connects a distribution main to a service lateral is called corporation stops (corp stop) and the valve that connects the service lateral to a meter is a curb stop. These are also referred to as meter and angle stops. They can be used to throttle flow without being damaged. • Flexing – The last style of valve based on how it operates is a “flexing” valve. These valves are either diaphragm or pinch style valves. The flow is reduced or stopped by a squeezing or pinching effect to obstruct the flow. The material inside of these valves need to be flexible and are commonly resistant to corrosion. Gate Valves Gate valves are one of the most widely used valves in a water distribution system. As previously mentioned their primary function is to start and stop the flow of water. These types of valves should not be used for throttling the flow of water as they can become damaged. The gate (slide) is lowered and raised by a hand wheel in above-ground installations and a nut with a key on below-ground installations. The face of a gate valve can become worn, especially if they are throttled and objects can become lodged under the gate, which prevents a proper seal. The gate picture above is the style used below the ground surface. The nut on top of the valve bonnet is operated with a “T” shaped key with a 2” square case that fits on top of the nut. The other gate valve pictured above is one used in above-ground installations and is operated with a handwheel. There are several different styles of gate valves, and they have various purposes. The list below identifies some of these valves: • Non-rising stem (NRS) – The below ground gate valves are considered non-rising stem. These valves take up less space and have the screw mechanism protected. • Rising stem – A rising stem gate valve is commonly used on fire systems. The reason is that it is easily detected if the valve is open or closed by the position of the stem. These types of valves are also called “outside stem and yoke” or OS&Y valves. The picture depicts this type of valve. When the stem is up, the valve is open. • Horizontal – In shallow below ground installations, horizontal gate valves are commonly used. They allow for low clearance and they are also easier to operate. Instead of having to lift the gate up when operating, the gate slides to the side. So, in addition to installations when the ground cover is minimum, large valves can also be horizontal gate valves. • Tapping, Cutting-In, Inserting – Several styles of gate valves are classified based on the use in construction practices. Tapping, cutting-in, and inserting valves are all used based on adding a valve in an existing distribution system. Tapping valves are used exclusively when a connection needs to be made to a water main. Hence, “tapping” into the water main. There are two types of taps, wet or hot tap and dry tap. A hot tap is done while the water main is in use and service cannot be disrupted. A dry tap is when the pipeline is shut down and the water is drained from the pipe. The two other methods of adding a valve to an existing water system are cutting-in or inserting. A pipe can be cut and a valve is added or a valve can be inserted into the pipe. The picture below is an example of an insertion gate valve. A cutting-in valve was one oversized end connection designed to be used with a cutting-in sleeve. The valve and sleeve are used together to facilitate installation of a new valve in an existing main. Pressure must be shut off for a short time. Inserting valves are installed when water cannot be shut off and the main cannot be depressurized. • Resilient seated – Gate valves are commonly made of various types of metallic materials. However, rubber, urethane rubber, and other synthetic materials are also used to make the closure member. In addition, the seat is made from this same material, providing a tight and complete closing seal. • Slide – Gate valves are sliding (sluice) valves, but a slide gate is a simple gate style valve. They are designed to release large volumes of water at one time and are often found in large agricultural systems. The gate or blade is relatively thin, they do not provide a completely tight shut off, and can be square, oblong, or round in shape. One of the main advantages of gate valves is the ability to block or let flow happen in both directions. They also offer little to no resistance when fully open and allow a clear waterway for the flow of water. In addition to the various styles of gate valves, they are classified into three (3) main types: double-disc, solid wedge, and resilient seated (as previously discussed). A double-disc gate valve is made up of two relatively loose-fitting discs that, when closed, are pressed against metal seats by a wedging mechanism. Water pushes past the upstream disc and allows the area between the two discs to become pressurized when the discs are in a closed position. The pressure is then released when the valve is opened. Some of these valves are equipped with a bypass to equalize the pressure on both sides to make it easier to open. The main disadvantage is the large frictional on the downstream disc making it difficult to lift off the seat. A solid wedge gate valve involves a closure member that is a single wedge guided into fitted, tapered seats. Although throttling is not recommended with gate valves, the solid wedge is more desirable because of the close guiding between the wedge and the body. Resilient seated gate valves were previously discussed. Other Valves Plug valves are a type of rotary valve and can be used to throttle and control flow. Even when open, they cause some flow resistance. There are three (3) basic types of plug valves, lubricated, non-lubricated, and eccentric. With lubricated plug valves, grease is used to lubricate the plug motion and to seal the gap between the plug and the valve body. On a non-lubricated plug valve, the valve is mechanically lifted up from or pushed down to the seat. An eccentric plug valve is a non-lubricated valve that rotates the plug and pulls away from the seat. Another type of rotary valve is a cone valve. These are limited in use because of their size and weight, but they are good for controlling flow and provide low flow resistance. Ball valves require a 90-degree rotation between the open and closed position, have low flow resistance, and are also suitable for throttling flow. Another common valve within the water industry is a butterfly valve. A butterfly valve is another valve that rotates. It has a disc similar to a gate valve, but this disc rotates on a shaft to open and close. Butterfly valves are easier to operate than a gate valve because as they open, the force of the water pushes against the opposite side of the disc helping to open the valve. The main disadvantage of a butterfly valve is that they have a high resistance to flow because the valve, even when fully open, is always in the flow path. The disc can also get damaged from the vibration of the flowing water. Since they have a short laying length (distance between each side of the flanges), they are used where space is limited. They are also lighter in weight and less expensive than gate valves. A check valve allows flow in only one direction and therefore has very specific applications. There are five (5) main types of check valves. • Slanting disc – Provide the lowest head loss of any check valve and are commonly used in larger pipelines to save on pumping costs • Cushioned swing – Results in a soft or cushioned closing of the valve when the flow of water stops • Rubber swing – Instead of the valve swinging on a hinge pin, like most other check valves, a rubber swing flexes to open • Double door – While all check valves are designed to allow flow in only one direction, a double door check valve is designed to have a greater seal when closed. These types of valve are more common in industrial operations. • Foot – These are special types of check valves installed on groundwater wells in order to prevent water from flowing backwards out of a pump and well piping back into the well when the well pump stops operating. They are installed at the bottom of a pump suction line and are used to prime the pump. Relieving and Controlling Pressure Pressure relief valves are very common in installations where pressures are high or where pressures can spike. These types of valves are used to control the limiting pressure within a system. The pressure is relieved by allowing the water flow to escape through an auxiliary passage out of the system. Preset pressure limits are designed to prevent damage to specific equipment or plumbing systems. Many residential homes and commercial businesses will have pressure relief valves installed if the incoming water pressure from the distribution system is higher than what is acceptable to the building being served. These valves are designed to open when pressures meet these preset values. A spring-activated disk balances the pressures on both sides of the system and opens when the inlet pressure exceeds the set value. Controlling pressure is another function of water system valves. If pressures are too low a water system is sometimes incapable of supplying the needs of customers. More importantly, if pressures are very low, the water system might be unable to provide adequate flows for fighting fires. If pressures are too high and relieving the pressure outside of the system is not possible, controlling valves can also be used. In some systems, both relief and controlling valves can be used. For example, the pressures within a system may fluctuate higher and lower beyond what are considered adequate pressures and a control valve would be installed. However, if the chance of extremely high pressures exists, then a relief valve would also be installed. Pressure control valves use hydraulic pilot systems which allow for a high pressure set point for high flow demands and a low pressure set point for low demands. The valve then automatically adjusts the pressure across the valve to accommodate these pressure ranges. This prevents the system from having too high or too low pressures. Backflow Prevention Preventing the contamination of a drinking water is an important aspect of a water distribution system. When a non-potable water supply is connected to a potable water supply the possibility of a cross-connection between these two sources exists. Therefore, every water utility needs to have a cross-connection control program. Cross-connection control and backflow prevention is discussed in another section of this text. In this section, we will look at the actual methods and devices used to prevent the flow of non-potable water back into a potable water supply system. The safest way to prevent a cross-connection is by not connecting non-potable supplies with potable supplies. When complete isolation of two supplies is not possible, a backflow method can be accomplished with an air gap. A proper air gap has the source supply discharging water into a receiving supply. This air gap distance between the source supply and the receiving supply must be two times the diameter of the supply pipe or one (1) inch, whichever is greater. When complete separation is not possible, a backflow prevention device can be used. These types of valves are reduced pressure principle, double check, or vacuum breakers. A reduced pressure principle (RP) backflow device consists of two spring-loaded check valves with a pressure-regulated relief valve between the two. Under back-siphonage conditions, both checks will close and the relief valve will open. If there is back-pressure in excess of the water main, both check valves will also close. If leakage occurs in the second valve, it will be allowed to escape through the center relief valve. It is important to install these devices high enough where the relief valve cannot be submerged in water. RP devices are used in commercial, industrial, and irrigation installations. Double check (DC) valve devices are similar to RP devices, except they do not have a relief valve in the center. Therefore, the protection is not as positive and should not be used where a health hazard may result. DC valves are commonly used in fire sprinkler installations. Installations where water use is only needed during an emergency, as with a fire sprinkler system, an RP or DC device can be installed with a meter attached. This meter will detect any flow of water through the device and allow the utility to bill the customer for this usage. These meters are referred to as detector assemblies. Therefore, an RPDA would be a reduced pressure principle detector assembly and a DCDA a double check detector assembly. Back-flow prevention devices are required to be monitored and maintained. Most cross-connection control programs require annual testing. There are other types of devices used where health hazards do not exist and are designed for intermittent use. These devices are called vacuum breakers. There are two main types of vacuum breakers, atmospheric and pressure. Common installations include lawn sprinkler systems, janitor sink faucets, and toilet flush valves. Atmospheric vacuum breakers must be installed beyond the last valve in the piping system. When the supply pipe is under pressure, the check valve closes against an upper seat to prevent leakage. When there is no pressure, the valve drops and allows air to enter the discharge pipe preventing back-siphonage. If there is continuous pressure the valve may malfunction. Pressure vacuum breakers are designed for use under pressure for long periods of time. They should not be used where back-pressure is possible on the discharge side and they must be installed above the highest fixture in the system. Valve Maintenance Since valves are mechanical devices, they need to be properly maintained. There is a wide variety of different types and uses of valves throughout the water industry and each type has its own maintenance requirements. As previously mentioned, backflow prevention devices require frequent testing and proper maintenance. The seats of a valve can become worn and damaged and need to be replaced periodically. The springs, which operate the valves and allow them to open and close, need to be replaced from time to time. This sort of maintenance is not only required with backflow devices, all valves need to be monitored and maintained. Distribution system valves are usually left in the open position to allow water to flow throughout the system. However, in the event of a leak or some other emergency, where the flow of water needs to be stopped, a valve needs to be closed. If a valve is left in the open position for years, closing it may prove to be difficult. Why? Because any mechanical device which has not been operated over a long period of time can become stuck or frozen. Therefore, it is important to operate valves on a routine basis. This routine maintenance operation of distribution system valves is referred to as valve exercising. Exercising a valve is nothing more than operating the valve from its current condition (open or closed) to the other position. Each valve type and valve size has a known amount of turns required to open and close it and the operator should be mindful of the number of turns in order to determine if the valve is in good working condition. If the valve cannot be operated to the required number of turns, it could be damaged or broken and might need to be replaced. A good valve exercise program should include all the information about the valve so the operator can make an assessment as to whether or not the valve is in good working condition. If not, then the valve should be put on a replacement schedule. Valves are an important part of any water utility system and provide a variety of uses, from stopping and starting flows, allowing flows in only one direction, reducing pressure, relieving pressure, and controlling pressure. These are some of the more critical uses of water system valves. Sample Questions 1. Which of the following valves is not compatible with a process known as “pigging”? 1. Butterfly 2. Gate 3. Ball 4. All are compatible 2. Which of the following valve should not be used for throttling? 1. Butterfly 2. Gate 3. Ball 4. Plug 3. Which back-flow device provides the most protection? 1. Double check 2. Reduced pressure 3. Vacuum breaker 4. All are equal 4. Which valve is used to prime a groundwater well pump? 1. Butterfly 2. Gate 3. Ball 4. Foot 5. Which of the following valves would be considered a “closing down” type? 1. Gate 2. Globe 3. Butterfly 4. Both 1 and 2

textbooks/workforce/Water_Systems_Technology/Water_140%3A_Water_Distribution_Operator_I_(Alvord)/1.06%3A_Valves.txt

In this chapter, we will examine water distribution fire hydrants and their uses. Student Learning Outcomes After reading this chapter, you should be able to: • Describe the different types of fire hydrants • Explain the different uses of fire hydrants • Identify the operational and maintenance criteria for fire hydrants From a very early age, we are exposed to fire hydrants. Many kids' storybooks have pictures of red fire hydrants and Dalmatian dogs. We start recognizing the red fire plug and associate it with firefighting. However, most fire hydrants we see every day are not red. They are yellow. The use of fire plugs or fire hydrants as we know them today dates back to the 1600s. After a devastating fire destroyed a large portion of London, predrilled holes were add to new water mains and plugs were installed above ground for access. Since early water mains were made out of wood, the early hydrants were holes that had above ground plugs, hence the term “fire plug”. By the 1800s, cast iron hydrants replaced the traditional fire plugs. Fire Hydrant Uses The most common and understood use of a fire hydrant is fighting fires. Public fire protection is important for any community and it is the responsibility of water utilities to provide fire hydrants in required locations and the water required for fighting fires. There are other uses of fire hydrants. Some of these uses include flushing water pipelines, storm drains, and sewers, street washing, public landscape watering, and construction. Let’s take a look at some of these less obvious uses. Flushing Water Pipelines, Storm Drains, and Sewers When a new water pipeline is installed there are various things that need to be done before the pipeline can be connected to the distribution system and used for public water supply. New pipelines need to be disinfected and sampled to make sure the water in the pipe is safe for human consumption. After this disinfection and sampling process, the water needs to be flushed out and replaced with fresh water. This flushing process is commonly performed by the use of fire hydrants. Water in pipelines can also become stagnant if there is little or no use. An example of this would be a cul-de-sac where there is little to no use. Perhaps it is a long cul-de-sac with only one home and the homeowners are out of town for an extended period of time. The water in the pipeline could become stagnant and when the homeowners return may notice some taste and odor problems with the water. If the water utility is notified of these types of issues they would oftentimes flush the water out of the pipeline to replace it with fresh water. Storm drains and sewers also need to be cleaned from time to time. If debris blocks the flow in these systems, hoses are often connected to fire hydrants in order to push the debris and flush these piping systems. It is important to make sure the potable drinking water distribution does not become contaminated from storm drains and sewers. Often times certain valves known as back-flow devices are used or water trucks are filled through fire hydrants and then these piping systems are flushed. Street Sweeping and Landscape Watering In order for city streets to stay clean, vehicles such as street sweepers are commonly used. A street sweeper will connect to a fire hydrant in order to fill up a tank and then the water is discharged to clean the street. A lot of streets have center medians with landscaping which include trees and other plant material. If these medians are not equipped with irrigation systems, water trucks are often used to water these plants. The water to fill these trucks comes from fire hydrants. Construction Construction needs water for various purposes. One of the most common uses of water (supplied through fire hydrants) is for dust control. During grading operations, heavy equipment moves and removes dirt, sometimes over large areas. This process of dirt moving creates dust. In order to control the dust, water trucks collect water from fire hydrants and spray it over the entire area to wet the dirt controlling the dust. Is Water From Fire Hydrants Free? Unlike water served to customers such as home or business owners, water coming from a fire hydrant is not metered. When a fire truck pulls up to a fire hydrant, connects a hose to the hydrant, and starts to fight a fire, the water used is not metered. In other words, there is nothing to track the amount of water used and there is no one paying for the water being used. Since fighting fires is a public service, it actually makes sense that the water used is not metered. There are some uses from fire hydrants, which should be metered, and the water paid for by the user. Most other uses of water from fire hydrants besides fighting fires is metered for use. Portable hydrant meters are used to keep track of the water used. These meters, often referred to as construction or hydrant meters, are temporary meters rented to the user. Since these meters are temporary in nature and can be used in multiple locations the user is sometimes asked to provide the meter reads. By charging for water used from fire hydrants there is accountability of the water and it also discourages the wasting of water. It is important for water utilities to account for all the water within a water distribution system. It costs the utility to pump the water throughout the distribution system, so when water leaves the system unaccounted for, there is lost revenue. This lost water is measured by utilities and is referred to as water loss. There are several ways water utilities monitor and control the use of water from fire hydrants. Specific meters are assigned and used only for connecting to fire hydrants. These meters are commonly referred to as construction or hydrant meters. Often times, deposit fees are charged to “rent” these meters. Deposits are designed to cover cost of the meter in case they are lost or damaged. These fees can also be used to maintain and service these meters to make sure they work and measure flow accurately. Some utilities use a permitting process to issue these meters. This process is designed to help track the meters being issued and often includes a fee, which provides the same coverage for maintenance and replacement costs. Parts of a Fire Hydrant There are several parts of a hydrant and can be broken into the upper and lower section. The upper section consists of the nozzle and head. The nozzles are the areas where hoses or meters can be connected and where the water flows from the hydrant. These connections are commonly 2 ½” and 4” in diameter, threaded, and caps are usually provided to cover and protect the threads. The top section of a hydrant can also be referred to as the bonnet. The bonnet is the top cover or enclosure. There is an upper barrel portion that sits above the ground and a lower buried portion, oftentimes referred to as the “bury-el”. This buried elbow portion is shown below. Types of Fire Hydrants On the surface, most fire hydrants look similar. They are usually molded in cast or ductile iron, bronze, and sometimes steel. They are typically constructed above ground with threaded openings for the attachment of hoses. However, there are a few different types of fire hydrants. The first two we will look at are the dry barrel and wet barrel hydrants. Dry Barrel Hydrants A dry barrel hydrant is exactly that…a hydrant with the barrel dry. The barrel of a hydrant is the body above ground and a section below ground. The picture below depicts the barrel. This type of fire hydrant is very common in areas where the weather drops below freezing. In these areas, the barrel of a hydrant needs to be dry in order to prevent the water in the barrel from freezing. If the water in a barrel of a fire hydrant freezes, then the ability of the fire department to access water in order to fight fires is impeded. There is a nut at the top of a dry barrel fire hydrant, which is connected to a stem. This stem connects to and operates a valve, which allows water to enter the hydrant barrel, and water can flow. There are two types of dry barrel fire hydrants: wet-top and dry-top. A wet-top dry barrel hydrant is constructed such that the threaded end of the stem and the operating nut sealed from water when the valve is open. A dry-top dry barrel hydrant has the threaded end of the stem sealed off from water in the barrel when the hydrant is filled with water and in use. This design reduces the possibility of the threads becoming fouled by sediment or corrosion. The type of operating valve can further classify a dry barrel hydrant. These types of valves include standard compression, slide gate, and toggle. • Standard compression – This type of hydrant valve closes the water against the seat of the valve to aid in providing a good seal • Slide gate – A slide gate is a gate valve similar to a distribution system gate valve • Toggle – This type of valve closes horizontally and the hydrant barrel extends well below the branch line. This type of valve is also called a “Corey” valve. Wet Barrel Hydrants Wet barrel hydrants are used in warm climates where the risk of freezing is minimal. Since most fire hydrants are above ground and exposed to the elements, it is important that the water inside the hydrant doesn’t freeze when the temperatures dip below freezing temperatures. However, it is also important that a fire hydrant flows water when it is opened. This is the design of a wet barrel hydrant. When the valve stem adjacent to a threaded opening is twisted open, water flows directly out of the hydrant. Locating Fire Hydrants Fire hydrants need to be properly located in order for ease of access and properly spaced in order to give proper coverage for firefighters. Hydrants are typically located at street intersections and spaced between 350 and 600 feet apart. The spacing is dependent on the type of structures in the area (residential, commercial, etc) and the density of the buildings. Commonly they are placed about two (2) feet from the back of curb face and located far enough away from buildings to allow the fire department to gain access without being too close to fire. When installed along public roadways on sidewalks, care must also be taken to install them so they do not impede foot traffic or wheelchairs. Since fire hydrants are commonly installed where there is vehicular traffic, the potential for one to get hit by are a vehicle is likely. Therefore, proper installation must be considered in order to provide the least amount of damage. Several methods are commonly used. One method is to use hollow bolts, which connect the flange above ground to the flange below ground. Another method employs the use of a “breakaway” flange. This type of flange is manufactured to split in the center. Both of these methods allow for the hydrant to break away from the below-ground barrel. This prevents the buried components from being damaged and allows for the hydrant to be reinstalled relatively easy without any excavation. Potential Problems As discussed above, hydrants are not just operated by water utility operators. Fire departments, City workers, construction workers, and others can and often do operate a fire hydrant for various reasons and uses. This presents a potential problem. Older hydrants may not seat (close) properly and leak after it is closed. Opening a hydrant at the end of a cul-de-sac may stir up sediment in a pipe causing water quality issues and concerns. Proper traffic control must be taken when a hydrant is open on public streets with traffic. When a hydrant is open, it can disrupt the flow of traffic by spraying water across lanes. Whenever a hydrant is open to flow onto the ground, proper drainage needs to be available. If storm drains and gutters are filled with debris, water may not be able to drain properly and some of this debris can be flushed into storm drains ending up in local waterways. Another problem that can occur when a hydrant is improperly opened and closed is something called “water hammer”. Opening or closing a hydrant too fast can cause the flow of water to move or stop too rapidly causing damage to pipes and other appurtenances. It is important to understand the need and various uses of fire hydrants. They play an important role to the surrounding community, public safety, safety to property, and a variety of other uses. Sample Questions 1. A fire hydrant referred to as a “Corey” style would be what type? 1. Flushing 2. Wet Barrel 3. Dry Barrel 4. None of the above 2. The base or buried portion of a hydrant is commonly called the ___________. 1. Bonnet 2. Cap 3. Nozzle 4. Bury-El 3. Approved use of a fire hydrant includes all of the following except? 1. Dust control 2. Fighting fires 3. Cooling the public during heat waves 4. Flushing sewers 4. Which of the following is an advantage of a dry-barrel hydrant? 1. Water is easily withdrawn by opening an operating nut 2. Water will not flow if the hydrant gets hit and knocked off its base 3. Water will not freeze in the hydrant body 4. Both 2 and 3 5. A wet-top fire hydrant is a type of ___________. 1. Wet barrel hydrant 2. Flushing hydrant 3. Dry barrel hydrant 4. All of the above

textbooks/workforce/Water_Systems_Technology/Water_140%3A_Water_Distribution_Operator_I_(Alvord)/1.07%3A_Hydrants.txt

In this chapter, we will examine water distribution meters and services Student Learning Outcomes After reading this chapter, you should be able to: • Describe the different types of water meters and services • Explain the different uses of water meters • Identify the operational and maintenance criteria for water meters Why Water Meters? What is the purpose and need for a water meter? Are water meters always used by water utilities? What does a water meter do and where are they used? What is a water meter? These and other questions will be answered in this text. Purpose of a Water Meter The primary purpose of a water meter is to monitor and record the amount of water being used by a customer. These customers can be residential homeowners, commercial buildings, industrial customers, other water utilities, and various other customers. The idea of “metering” water usage can be traced back to the early sixteenth century. However, If it rained enough to water crops and landscaping, if water was readily available equally for everyone, there might not be a need for water meters. However, it wasn’t until the early nineteenth century when water meters began to be more widely used. The increase in use coincided with the growth of urbanization and industrialization. While metering the flow of water is very common among residential and commercial drinking water supply customers throughout much of the world, it is less common with irrigated agriculture customers. Metering is also less common in rural areas and in areas where water is in abundance. In many parts of the world, water is not always easily accessible and in order for the “people” delivering the water to communities to recover all the costs associated with delivering this coveted resource, meters are used. One of the main uses of a water meter is to measure the amount of water delivered to customers. However, meters are used to measure other volumes of water in addition to what is delivered to a customer. Types of Water Meters While there are many different styles of water meters, they are all based on two main methods for measuring flow: displacement and velocity. Displacement meters physically move (or displace) a given amount of water passing through the meter. Velocity meters measure the speed at which the flow of water is passing through the meter. There are a number of different water uses and meters are commonly selected based on size and need. For example, you wouldn’t want to select a small meter if very high volumes and flows are needed. Likewise, you wouldn’t want a large meter for a single-family home. Displacement meters are commonly used in small to medium flow installations and velocity meters in areas where large flows are required. Positive Displacement Meters Positive displacement (PD) meters are commonly used for single-family residential water uses. They are very accurate in measuring low intermittent flows. They work by means of a nutating disk or rotating piston, which creates a rotary motion transmitting to gears and then to the register. PD meters are not designed to operate at full flow for extended periods of time. Normal flows for a PD meter should not be more than approximately one half of the maximum capacity in order to extend the life of these types of meters. Common sizes range in diameters from 5/8” to 2”. If PD meters are too large for the required use, lower flows will not be properly registered. For example, if a 2” PD meter is used for a one-bedroom apartment where only indoor water use occurs, lower flows such as when someone is brushing their teeth or filling a glass of water may not be accurately measured. PD meters almost never over register and continuous operation at the maximum flow rates will quickly destroy the meter. They are designed with threaded ends and are not tapered. Therefore, a coupling with a gasket is needed for installations. This type of design allows for quick and easy installation and removal. Piston PD meters operate by the means of a piston, which moves back and forth as the water flows through. A specific quantified volume is measured for each piston rotation. This rotating motion is transmitted to a register through a magnetic drive connection and series of gears. Nutating-disk PD meters use a measuring chamber containing a flat disk. As water flows through, the disk wobbles and rotates (nutates) sweeping out a specific volume of water on each cycle. The rotary motion is transmitted to a register. Velocity Meters Velocity meters measure the flow through a chamber of specific size and known capacity. The speed of the flow is converted into volumes correlating to water usage. There are several types of velocity meters, which include, single-jet, multi-jet, turbine, and propeller meters. Electromagnetic and ultrasonic meters are also technically velocity type meters, but will be discussed later in a separate section. Multi-jet meters use a multiblade, multiport rotor mounted on a vertical spindle within a measuring chamber. Water enters this chamber through several tangential orifices around the circumference and leaves through another set of orifices set at a different level. The “jets” of water rotate an impeller where the rotation transmits to a register. Installations requiring low flows, multi-jet meters range in sizes from 5/8” to 2”. Internal strainers are often used in order to protect the jet ports from getting clogged. Unlike PD meters, multi-jet meters can overregister. Multi-jet meters have two basic designs. One design is referred to as a “wet” register design and the other a “dry” register. In a dry register design, the register, which sits at the top of a meter, can be removed without shutting the water supply off. This is a desirable design when a register stops working or becomes damaged and can be replaced easily without disrupting usage. Turbine and propeller meters measure the flow of water by means of a rotor. Each revolution of the rotor is proportional to the volume of water. The rotor has blades, which are angled to transform energy from the flow stream into rotational energy. The rotor shaft spins on bearings and as the water propels through the meter faster, the rotor spins proportionally faster. The accuracy is not good at low flow rates because there is some drag between the rotor and the bearing, which slows the rotation of the rotor. Propeller meters are similar to turbine meters. The main difference is with the rotating element. A propeller is made of thick molded plastic and faces directly into the flow and is suspended by a single bearing assembly. In contrast, the thinner rotor in a turbine meter is supported on both sides by two lighter weight-bearing assemblies. Common installations of turbine meters are uses where the flow is high and the variance in the flow is minimal. For example, irrigation system flows are commonly measured using a turbine meter (below right). In these installations, the flow is constant and steady. Propeller meters (below left) have similar uses, but are more commonly found on source supply installations, for example on a groundwater well. These installations also have a constant steady stream of high flows. Venturi and Orifice Meters A venturi meter consists of an upstream reducer, a short throat piece, and a downstream expansion section. An increase in the flow velocity results in a corresponding pressure drop and the flow rate can be deduced. As the flow of water moves through the contraction in the pipe, it speeds up and so, the pressure drops. By measuring the upstream and downstream pressures, the fluid velocity and flow rate can be calculated. An orifice meters operates in much the same way as a venturi meter. A thin plate with a hole in the center of it is installed between two flanges. The flow rate is then calculated by measuring the pressures on both sides of the plate. These types of meters are considered differential pressure meters. Magnetic and Ultrasonic Meters Ultrasonic and magnetic meters operate in a similar fashion. They measure the rate of flow without any moving parts to disrupt the path of the flow. Magnetic (or Mag) meters measure the flow of water using an electromagnetic field resulting in a potential difference proportional to the flow velocity perpendicular to the electrical sensors. The pipe must be properly insulated in order to prevent corrosion from the electrical current. Ultrasonic flow meters use ultrasound frequencies to calculate a volume of flow. Transducers are used to emit a beam of ultrasound against the direction of flow. The pulses are sent in opposite diagonal directions and the sound changes with the velocity of the flow. These types of meters tend to have higher initial costs, but the ongoing maintenance costs are minimal because there are no moving parts to maintain or replace. Weirs and Flumes Some water systems such as when an open channel is providing a water supply to a community, a different structure is needed to measure the flow. In this particular system, a traditional style meter is not appropriate. An obstruction referred to as a weir is placed across the flow path to measure watersheds, creeks, and stream flows. The depth to which the water rises above the bottom of the weir is directly proportional to the flow. There are two main types of weirs, rectangular and V-notch. Rectangular weirs are constructed in a variety of different configurations including contracted, suppressed, broad crested, and sharp crested. • Contracted weirs are constructed where the width of the notch is less than the width of the channel. • Suppressed weirs have the notch as wide as the width of the channel. • Broad crested weirs have a flat horizontal surface at the crest ranging from 6” to 15” and are usually made of concrete. • Sharp crested weirs are made of fiberglass, corrosion-resistant metal, or wood. V-notch weir angles are commonly 30°, 45°, 60°, and 90°. The larger the angle, the higher volume flows are measured. These types of weirs are always sharp crested design and they measure smaller flows than rectangular weirs. The rate of flow passing over the crest of any type of weir is directly proportional to the depth of water measured from the crest to the water surface. The depth measurement is always made at a distance of at least three times the height upstream of the weir so that the measurement is not affected by the sloping surface of the water approaching the weir. For example, if the weir is 10 feet, then the flow measurement would be collected approximately 30 feet upstream of the weir. The flow depth can be automatically determined and recorded by a float and a recorded installed in a device called a stilling well. Flumes are similar to weirs and are also designed to measure the flow in an open-channel section. The principal advantage of a flume is that there are no vertical obstructions as there are in weirs. A flume narrows in the center to increase the velocity of the flow. The velocity through a flume must be high, which also helps keep the flume clean. Flumes are generally more expensive than a weir. The most common type of flume is the Parshall flume. The capacity is determined by the width of the throat of the flume, In Parshall flumes, the widths range from 1 inch to 50 feet. The depth of the flow at a particular point in the flume is directly related to the rate of flow. As with weirs, flume depths can be made by a staff gauge or automatically with a transducer. Compound Meters At times both low and high flows need to be measured accurately. As previously discussed, most meters are designed to measure either low or high flows. For example, PD style meters are not good for measuring high flows and turbine-style meters are not sufficient at measuring low flows. Installations where both low and high accurate flow measurements are required; a compound meter can be used. Compound meters usually consist of a larger turbine meter, a smaller positive displacement meter, and an automatic valve to switch between the two meters. Water passes through the small meter until a certain velocity is reached and then the valve actuates to divert the flow to the larger turbine meter. Two standard meters can also be connected together to provide the same function. Meter Selecting and Installation As previously mentioned, meters are often selected based on the volume of water needing to be measured. Meters are commonly one size smaller than the diameter of size of the service lateral. For example, if the service lateral is 1” in diameter serving a residential home, the meter might be ¾” in size. In a typical residential housing track, it is common to have 1” service laterals and ¾” meters. However, in commercial areas, the service lateral might be sized for greater usage compared to residential units, but still might have smaller meters. For example, a 2” service lateral might be installed for a bookstore where the only usage might be a single restroom and a ¾” meter might be installed. However, if this bookstore changes the use to a restaurant and higher flows are required, the service lateral is already sized appropriately and only the meter would need to be replaced with a larger one. Therefore, it is important to size services for future potential uses. Residential meters are typically 5/8” or ¾” in size depending on water demand. However, in some communities, residential homes might require internal fire sprinkler systems, in which case the meter size might need to be larger. There are various plumbing codes for sizing meter services and can also be dependent on the number of internal plumbing fixtures. Commercial businesses and multi-family residential homes commonly have meter sizes of 1”, 1 ½”, and 2”. If accuracy at low rates is not important and if typical flow rates between 5 % and 35% of the maximum rated capacity then a positive displacement style of meter is adequate. If accuracy of low flows is required, as well as being able to accurately measure higher flows then a compound meter should be used. Installations requiring large capacity and low flow accuracy, and flows at 10% to 15% maximum rating then a turbine meter should be selected. Meters are generally installed in concrete or polymer boxes located in the parkway, between the curb and the sidewalk. In very cold climates, meters are installed in deep meter pits or inside buildings. Larger meters are usually installed in precast concrete vaults. Whenever possible, meters should be installed in areas protected against flooding. They should be installed with an upstream and downstream shutoff valve. A meter, angle, or curb stop is the shutoff valve on the upstream side of the meter and there is usually a small gate, globe, or ball valve on the customer (downstream) side of the meter. Meters need to be accessible for maintenance, inspection, and reading and should be protected from freezing. Whenever a utility operator visits a meter, the condition of the meter box and lid should also be checked to make sure there is not a public hazard and that they are in good condition. Registers should be sealed and should have a means of preventing tampering. Depending on the type of usage, meters can also be installed with a bypass. If it cannot be interrupted, a bypass allows for water service to be maintained while the meter is removed or repaired. Some meter installations can have multiple meters installed in series. This type of setup is a manifold installation. They are used when high flows are required and flow cannot be interrupted. One meter at a time can be removed or repaired without disrupting service. Meters up to one (1) inch in size usually have threaded connections each side of the meter. Larger meters tend to have flanged connections. Sometimes a yoke can be used to simplify meter installations in hard to reach areas. Yokes hold the stub ends of the pipe in proper alignment and spacing to support the meter. Yokes also provide a cushion against stress and strain in the pipe. The image below shows a typical yoke. As previously mentioned, meter boxes are usually installed on public property, but close to the property line. They should be installed in areas to protect against damage from vehicles. If a meter must be installed in a driveway, steel lids are usually sufficient to help protect the meter from vehicles. Meter couplings or flanges should be located where they are accessible and the dimensions of the meter box or vault should be adequate in size and specified prior to installation. If the meter is installed in a building, then a special valve needs to be installed on the upstream side of the service line. A curb box in either an arch-style or Minneapolis style is used in these situations. An arch-style curb box fits loosely over the top of the stop valve. These installations are adequate if the soil is firm enough. If the surrounding soil is loose, it may work its way into the box or the box may shift making access to the stop valve difficult. The Minneapolis style curb box has threads at the bottom and screws onto special threads on the top of the meter. These installations do not have the issue of shifting or dirt entering the box, but if there is damage to the curb box, damage to the meter and service line can occur. Meter Reading Meter accuracy is important in order to adequately bill for the amount of water actually used. As flow passes through the body of a meter, the volume is transmitted to a register. Old style meters were equipped with circular or round registers. Some gas meters are still this style. The problem with this type of register is the difficulty to read. It is now common to have a register similar to a car odometer. Some are equipped with one or two fixed zeros. The reason for this is because water usage is commonly billed per hundred cubic feet. Therefore, with two fixed zeros, the first number to register on the meter is a one (1) with two trailing fixed zeros, indicating one hundred (100) cubic feet. Some larger meters might have a multiplier of ten (10) of one hundred (100) times. This is because usage is high and it makes it easier to keep track of this large volume of water. There are several ways a meter can be read. The simplest and most common of reading meters is to read them directly. This requires a worker to visit each location where the meter is installed and physically read the register. It requires the meter to be accessible and clean so the register can be read. By visiting meters routinely, workers can see if the meter is being tampered with, damaged, or needs to be replaced. However, this type of reading process can be difficult in cold climates and some customers do not like meter readers visiting their homes. There is also the chance for human error. As technology advances, so do the ways meter reads can be collected. Remote meter reading is becoming more and more common. There are several types of remote meter reading technologies. One remote meter reading technology is referred to as “touch probe” reading. The meter register is connected to touch sensor with a wire. A handheld unit is connected to a probe and is placed on the touch sensor transmitting the meter read. This technology still requires a meter reader to visit each location, but there is less labor involved since the meter box lid does not have to be lifted. Another remote meter reading process is called automatic meter reading (AMR) or “drive-by”. Special electronics are attached to the meter and send out a radio frequency signal. Meter readers’ drive by each location with a computer and a receiving device to pick up the meter reads through the radio frequency signal. The last remote meter reading process is called automatic metering infrastructure (AMI). This type of technology uses radio frequencies with large antennas installed in specific locations or cellular data to transmit meter reads instantly on demand. This type of system requires significant upfront costs, but does not require any labor to read the meters. Some utilities are moving to this type of meter reading technology in order to provide customers real-time data on their water usage. This can assist utilities with their conservation efforts. All meters are designed to measure flow velocity where the flow is laminar. If the flow has any turbulence, meters can and will often incorrectly register the meter read. Any kind of pipe bend, valve, obstruction, or change in flow direction get cause turbulence. Therefore, meter manufacturers often specify straight pipe lengths before and after the meter. These distances are typically expressed in pipe diameters. As a rule of thumb, five (5) times the pipe diameter before the meter and two (2) times the diameter after the meter. For example, if the pipe is twelve (12) inches in diameter, there should be sixty (60) inches of straight pipe before the meter and twenty-four (24) inches of straight pipe after the meter. One of the main reasons a worker should visit a meter regularly is because some customers will attempt to steal water. Some common ways customers attempt to steal water are removing the register, turning the meter backward, or removing the meter. In addition to visiting a meter routinely, seals can be placed on the meter. Seals do not necessarily prevent pilferage, but if the seal is broken, a worker can quickly identify if the meter has been tampered. Meter Testing Since meter accuracy is important, meters need to be tested to make sure they are operating correctly. Meter manufacturers often include testing results with new meters. In addition, some utilities randomly test new meters to make sure the manufacturer test results are correct. As meters age over time, they can start to under register. Therefore, a routine meter testing program is often recommended. Some utilities randomly remove meters at various ages in order to see if they are still registering properly. Customers can also request for a meter to be tested if they think their meter is not registering correctly. Meters should also be tested after any maintenance. Some meters (usually larger ones) are testing in place, while smaller meters are typically removed from service and placed on a test bench. Regardless of the location, meters are tested in a similar fashion. A known volume of water is flowed through the meter and the register is compared to this volume. In addition, various flow rates are flowed through the meter, each time comparing the known volume with the volume recorded on the meter register. There are accuracy limits on the different rates of flow that are considered acceptable. Positive displacement meters are tested against a minimum, intermediate, and maximum flow rate, while larger meters might have four (4) or five (5) different flow rates. Below is a set of recommended accuracy limits for different types of meters. Positive displacement, multi-jet, and turbine meters have an accuracy range of 98.5% to 101.5%. This means if 100 gallons of water are flowed through the meter and the meter registers between 98.5 and 101.5 gallons, then the meter is determined to be accurately measuring flows. The limits for propeller meters are 98% to 102% and compound meters 97% to 103%. Sample Questions 1. Which of the following meters would be most likely to over-register? 1. Turbine 2. Positive displacement 3. Multi-jet 4. All of the above 2. A compound meter is used when ___________. 1. Low flow accuracy is required 2. High flow accuracy is required 3. Constant high velocities at low flows are required 4. Both 1 and 2 3. Positive displacement meters operate by means of a ___________. 1. Rotor 2. Nutating disc 3. Propeller 4. Electromagnetic waves 4. Over time meters tend to ___________ and should be ___________. 1. Over register, replaced 2. Under register, replaced 3. Over register, tested 4. Under register, tested 5. Which of the following would not be considered a flow meter? 1. Weir 2. Volute 3. Venturi 4. Flume

textbooks/workforce/Water_Systems_Technology/Water_140%3A_Water_Distribution_Operator_I_(Alvord)/1.08%3A_Meter_Services.txt

In this chapter, we will examine the pumps that move water throughout a water distribution system. Learning Outcomes After reading this chapter, you should be able to: • List the various types of pumps found in the water industry • Identify the various components of pumps • Differentiate the various purposes of pumps in the water industry Purpose of a Pump Without a pump, water would only flow through gravitational forces of gravity. This would be fine if the source of water was always higher than the user. However, we know that this is not the case. In addition to pumps being needed to deliver water to customers at varying elevations, pumps are used to “lift” water over mountains to deliver it to treatment plants. Pumps are used to “push” water through treatment systems and to “inject” chemicals into a stream of flowing water for treatment purposes. As you can see, there are a lot of purposes for pumps in the water industry. This chapter will present a variety of examples where pumps are used, the various types of pumps, and how they are used to keep water flowing in a distribution system. There are two main types of pumps, which are primarily used in the water industry; these are positive displacement and variable displacement pumps. Positive Displacement Pumps Positive displacement pumps “displace” liquid by mechanical action providing constant flow at a fixed speed, despite changes in pressure. There are two main types of positive displacement pumps: Rotary and Reciprocating. Positive displacement pumps move fluids by trapping a fixed amount and displacing (moving) the trapped volume into a vessel such as a pipe. A good example of a positive displacement pump used in the water industry is for chemical injection such as chlorine disinfection. Below is a picture of a positive displacement pump taking a liquid chemical from a container and pumping it into a pipe. Positive displacement pumps are commonly used for chemical injection because of their ability to operate against a variety of discharge pressures while maintaining a constant given speed. This enables a consistent chemical dosage. One of the main disadvantages of positive displacement pumps is that they do not have a shutoff head. Therefore, if a positive displacement pump operates against a closed valve it will cause the discharge line to burst and/or cause damage to the pump. Positive displacement pumps include gear, lobe, peristaltic, screw, piston, and rotary. Variable Displacement Pumps Variable displacement pumps deliver the same volume or flow of water against any head pressure within the operating capacity. Typical types are piston (reciprocating) pumps and screw or squeeze displacement (diaphragm) pumps. There are various types of variable displacement pumps and include; jet, turbine, and centrifugal. The most common in the water industry are turbine and centrifugal. Centrifugal Pumps Centrifugal pumps are some of the most common types of pumps used in the water industry. They convert rotational kinetic energy to hydrodynamic energy. Electric motors provide this rotational energy. Centrifugal pumps raise the water by a centrifugal force, which is created by a wheel referred to as an impeller. This impeller revolves inside a tight casing. Water enters the pump at the center of the impeller referred to as the eye. The impeller throws the water outward toward the inside wall of the casing by the centrifugal force resulting from the revolution of the impeller. Water then passes through the casing and emerges at the discharge point under pressure. There are two main types of centrifugal pump casings, volute and diffuser. • Volute casing – Volutes are designed to utilize the incoming velocity of the liquid entering the impeller and converting this velocity into pressure. The impeller is housed in a spiral-shaped case and located offset of the center of this casing. This allows pressure to build as the impeller spins counter-clockwise and the distance between the volute and the impeller increases gradually. These are typically single-stage designs and are used for large capacity and low head applications. The impeller of a centrifugal pump is either open, semi-open, or closed design. Open impellers are generally used to pump raw water. This is because raw water may carry with it some solids, which would damage the other impeller designs. Semi-open impellers can pump liquids with some solids, but not as much as the open design. Closed impellers generally pump finished treated waters and provide a controlled area to channel water through the impeller. • Diffuser casing – A typical diffuser casing has many vanes in order to build pressure at the point where the edge of the casing approaches the edge of the impeller. Diffuser designs are generally more compact compared to volute designs. There are five (5) distinct types of centrifugal pumps in the water industry: turbine (diffuser), volute, axial flow, radial flow, and mixed flow. • Turbine – These types of centrifugal pumps are most commonly used in well pump operations. The impeller is surrounded by diffuser vanes, which provide gradually enlarging passages in which the velocity of the water leaving the impeller is gradually reduced, thus transforming velocity head to pressure head. Turbine pumps often come in multiple stages. The stages are bolted together to form a pump bowl assembly. The function of each stage is to add pressure head. The volume lifted and efficiency is almost identical in each stage. • Volute – These types of pumps were discussed earlier and are used in high flow and low-pressure installations and are commonly single-stage pumps. They are either close or long-coupled. Close-coupled pumps have the impeller mounted directly on the motor shaft. A long-coupled (or frame-mounted) has a pump with separate motor bearings and is connected to the motor by a coupling. • Axial Flow – These types of pumps are in-line and work on a vertical plane in relation to the water. Axial flow pumps offer very high flow rates and very low amounts of pressure head. • Radial Flow – This type of centrifugal pump discharges the fluid radially (at right angles to the pump shaft). Radial flow means the pump operates on a horizontal plane to the direction of flow. • Mixed Flow – A mixed flow pump is a cross between an axial flow and radial flow pump. The impeller sits within the pipe and turns, but the turning mechanism is essentially diagonal. The centrifugal force moves the water while accelerating from the axial direction for the impeller. Pump Components A pump is made up of a number of different components. The following list composes the main mechanical components of a centrifugal pump. Each item will be discussed. • Casing • Single-Suction Pumps • Double-Suction Pumps • Impeller • Wear Rings • Shaft • Shaft Sleeves • Packing Rings • Lantern Rings • Mechanical Seals • Bearings • Couplings Some of the components above have been previously discussed, so they will only be mentioned again briefly below. Casing Pumps casings are designed to retain pressure and to seal off the inside of a pump to prevent leakage. In centrifugal pumps (as previously explained) the casing surrounds the pump rotor transmitting energy to the fluid by means of an impeller, which is mounted on a rotating shaft. In positive displacement pumps, the casing surrounds the rotary or reciprocating displacement elements. All casings have inlet and outlet nozzles, which direct the flow into and out of the pump. Inlet nozzles are referred to as suction nozzles and outlets are referred to as discharge nozzles. Single-Suction and Double Suction Pumps Many pumps used in the water industry are single-suction pumps. In single-suction pumps, water enters the impeller from one end and discharges across the casing. The fluid moves from the impeller center to the peripheral region of the pump. Another type of pump based on its suction is termed a double- suction pump. In a double-suction pump, the inlet water enters on both sides of the impeller. These are commonly referred to as a horizontal split-case pump. The casing is split into two halves along the centerline of the pump shaft. Impeller Impellers are unique to centrifugal pumps. They rotate inside the pump casing transferring energy from the motor, which drives the pump to the fluid being pumped. The fluid is accelerated outwards from the center of the rotation. The open inlet portion of an impeller is often referred to as the “eye”. According to the Swiss mathematician and physicist Daniel Bernoulli, pump impellers rely on the principle that states an increase in fluid velocity is accompanied by a decrease in pressure or potential energy (and vice versa) in order to operate. Wear Rings In order for impellers to rotate freely within a pump casing, a small clearance needs to be maintained between the casing and the impeller. To minimize damage to the rotating impeller, a set of wear rings are often attached to the impeller and/or the pump casing to allow this small clearance without causing wear to the impeller and casing. These wear rings are designed to wear and be replaced through proper maintenance. Shaft and Shaft Sleeves Impellers are mounted on a metal rod commonly made of a nickel alloy or stainless steel referred to as a shaft. Shafts transmit the rotating energy to the impeller. Shafts can be solid or hollow. Solid shafts are connected near the bottom end of a motor, while a hollow shaft extends through the motor shaft and is joined at the motor’s crest. Hollow shaft pump motors are most commonly used for deep groundwater wells. A special tool referred to as an arbor press (or gear puller) is required to remove the impeller from the shaft. A pump shaft sleeve is a hollow tube, typically made of metal and is placed over the shaft in order to protect it as it passes through the packing. These cylinder-shaped metal tubes are protecting the shaft from corrosion and wear and are designed to be replaced as needed. Packing Rings and Stuffing Box vs Mechanical Seals At the point where the shaft extends out of the pump casing, leakage can occur. In order to prevent or reduce the amount of leakage, packing rings or mechanical seals are used. Up to six rings can be used and need to be staggered 90 degrees apart beginning at “twelve o’clock”. The next ring is installed at “three o’clock” and so on. The packing rings are installed in an assembly called a stuffing box. Mechanical seals can be used instead of packing rings. They are more expensive, but typically last longer, allow minimal to no damage to shaft sleeves, and offer less maintenance. The main downside to mechanical seals is that when they fail, they fail suddenly and they are fairly difficult to replace. In contrast, packing rings require monitoring and adjustment, but are much easier to replace. The picture above is an example of how packing rings are staggered. Also placed in the stuffing box are lantern rings. They are designed to prevent air from entering the pump casing. Pump discharge water is fed into the ring and flows out of it through a series of holes leading to the shaft side of the packing. Water flows both towards the pump suction and away from the packing gland acting as a seal preventing air from entering the water stream and provides lubrication for the packing. Bearings Bearings within a casing (cage) of their own are used to allow the shaft to spin the impeller with minimal friction. The type of bearing used is dependent on the type and size of pump. Most pumps within the water industry have ball-type radial and thrust bearings. These are either grease or oil lubricated. One common feature among bearings is that they usually start to get noisy before they fail. Couplings When a pump is mounted on a frame, separate pump shafts are connected together by a coupling. The coupling transmits the rotary motion of the motor to the pump shaft. They are designed and installed to allow slight misalignment between the pump and the motor. This allows the shock from the motor start up to be absorbed. There are two types of couplings: flex and mechanical. The main difference between the two is that flex couplings are installed dry and require no lubrication and mechanical couplings require lubrication. Pump Operation Whenever there is machinery with moving parts, friction occurs causing noisy operation and the potential for the development of heat. Therefore, motor and pump temperature, vibration, noise, and other parameters should be monitored. There are various sensors that can be used, but the most efficient way to monitor for these things is direct observation. If the surface of a motor unit is substantially warmer than normal, it should be shut down. Experienced water utility operators commonly get to know the normal sound of pumps and motors as well. However, there are vibration detectors, special thermometers, temperature indicators, and various types of sensors can be installed to monitor these parameters. If the temperature, vibration, or some other factor being measured is out of a specified range, then alarms can sound or signals can be sent. In some instances these sensors can shut down these devices automatically. Cavitation Pump speed is also another parameter to monitor. Speed switches or contacts can be provided to monitor and turned off pumps at certain times. Under certain speed conditions, when the pressure acting upon the water falls to or below the vapor pressure of the water, it will begin to vaporize. This will create vapor pockets. At higher pressures, the pockets collapse and a rumbling noise is created. This rumbling, popping, crackling noise is referred to as cavitation. Suction cavitation occurs when the net positive suction head available to the pump is less than what is required. Under these conditions, the pump sounds like it is pumping rocks. There will be high vacuum (suction) pressure readings will occur on the suction line and low discharge pressures with high flows on the discharge side. This can be caused by several things, which include, a clogged suction pipe, a suction pipe which is too long, a suction pipe diameter too small, suction lift too high, and a valve on the suction line only partially open. Discharge cavitation occurs when the pump discharge head is too high where the pump runs at or near shutoff. A similar sound to suction cavitation occurs, resulting in high discharge pressure readings and lower flows. Similar conditions cause discharge cavitation including, a clogged discharge pipe, a discharge pipe that is too long, or a diameter too small, the discharge static head is too high, or the discharge line valve is partially closed. In addition to the noise created by cavitation, pump impellers and bowl surfaces can become pitted. Fluctuations or reductions in yield can occur and erratic power consumption can also be a result of cavitation. Avoiding Cavitation In centrifugal and propeller pumps, cavitation can be avoided by preventing the following conditions: • Avoid heads much lower than the head at peak efficiency of the pump • Avoid capacity much higher than the capacity at peak efficiency of the pump • Avoid suction lifts higher or positive heads lower than recommended by the manufacturer • Avoid speeds higher than the manufacturer’s recommendations • Avoid liquid temperatures higher than that which the system was originally designed Pump design is an important process when selecting the correct pump for specific operational uses. Using various pump sizes is one way of controlling flow rates and preventing inefficient operations. Variable speed motors or pump drives are other ways to control flow. Discharge valves can also be throttled (partially closed), but this can lead to valve damage or inefficient operations. However, this process can be utilized in specific circumstances. Starting and stopping pumps too often can cause excessive wear and increases power costs. Variable speed motors are one solution to too many starts and stops of a motor. Daily operations, storage needs, and system pressures should all be evaluated in order to select the correct pump and motor. Pumps are one of the most important components of any water utility system. They bring water from deep underground to the surface and they distribute water throughout the distribution system. They are used in treatment plants to move water through the treatment process. In areas where the topography varies, pumps are used to lift water to these various elevations. Pumping water requires electricity and this creates a significant cost to water utilities. Water utilities greatest expense is quite often the cost of pumping water. Sample Questions 1. Which of the following is a pump casing? 1. Venturi 2. Weir 3. Volute 4. All of the above 2. Which of the following pumps is the most common pump in the water industry? 1. Piston 2. Turbine 3. Positive displacement 4. Centrifugal 3. A negative aspect of mechanical seals is ___________. 1. They fail suddenly 2. They are difficult to adjust 3. They don’t last long 4. None of the above 4. Lantern rings are designed to ___________. 1. Provide a small amount of leakage to cool the pump 2. Fail as the pump wears 3. Prevent air from entering the pump casing 4. None of the above 5. Double suction pumps are commonly referred to as ___________. 1. Centrifugal pumps 2. Turbine pumps 3. Dual split face 4. Horizontal split case

textbooks/workforce/Water_Systems_Technology/Water_140%3A_Water_Distribution_Operator_I_(Alvord)/1.09%3A_Pumps.txt

Student Learning Outcomes After reading this chapter, you should be able to: • Explain the different groundwater systems • Identify the above ground and below ground components of a well • Describe the different methods of drilling wells Groundwater Sources of Supply Groundwater is one of the most important sources of supply of fresh drinking water throughout the United States. Beneath the earth’s surface, there are soil formations where water can be extracted in large volumes. These underground soil formations are referred to as aquifers. An aquifer is an underground layer of water-bearing permeable rock formations or unconsolidated materials such as sand and gravel. Aquifers There are two main types of underground systems (called aquifers) where water is stored and can be extracted. These are called: • Unconfined Aquifer – A natural underground layer of porous, water-bearing (strata) materials (sand, gravel) usually capable of yielding a large amount of supply of water • Confined Aquifer – A natural underground layer of porous, water-bearing materials (sand, gravel) separated by impermeable layers of materials (clay) The spaces and fractures in the geologic materials underground store water which can be extracted. This material can be classified as consolidated or unconsolidated. Consolidated aquifer systems are less common and consist of materials such as sandstone, shale, granite, and basalt. The more common underground geologic material contains unconsolidated sediment containing granular material such as sand, gravel, silt, and clay. Alluvium aquifers (sand, gravel, and silt deposits by rivers are some of the more common unconfined aquifers. Since these aquifer systems generally lie within river beds, they have a direct connection to the ground surface and therefore are more susceptible to contamination. Any contamination deposited on the ground surface has the potential to percolate (“trickle through”) the sediments into the aquifer. Wells In order to extract water out of the ground, a well must be drilled. A groundwater well is a structure constructed in the ground through various methods in order to extract or pump water from underground aquifers. They can be as simple as a deep hole with supports to keep the hole from collapsing and the water is withdrawn using a bucket. Or, they can be thousands of feet deep and constructed with steel reinforcement columns and use pumps to extract the water. Regardless of the type of well, this source is an important resource for communities throughout the world. In this section, we will focus on water utility groundwater wells. There are three (3) main types of groundwater wells. These can be described as: • Bored or shallow wells: These are usually bored into an unconfined water source, generally found at depths of one hundred (100) feet or less. • Consolidated or rock wells: These are drilled into a formation consisting entirely of a natural rock formation that contains no soil and does not collapse. These are typically around two hundred (250) feet. • Unconsolidated or sand wells: These are the most common type of drinking water wells and are drilled into a formation of soil, sand, gravel, and clay material. If not supported, these wells will collapse upon themselves. Well Components There are both underground and above ground components to a well. These components channel the water into a pipe, lift the water up from below the ground, and allow the water to flow above ground and into a distribution system. First, we will look at the above-ground surface features of a well, these are: • Well casing vent • Gravel tube • Sounding tube • Pump pedestal • Pump motor base • Sampling taps • Air release vacuum breaker valve • Drain line (Discharge to waste) Well Casing Vent When a well is in operation, the water in the well starts to rise in the column pipe of the well. However, there is an air space between the water and where the water is being pumped. This “air” needs to be released from the column pipe. The well casing vent provides this release. It prevents vacuum conditions inside a well by admitting air during the drawdown period when the well pump is first started and it prevents pressure buildup inside a well casing during by allowing excess air to escape during the well recovery period after the well pump shuts off. Gravel Tube When a well is drilled, a pipe is lowered into the ground. Water enters into this pipe from the surrounding soil. We want water to enter the well, but we do not want the surrounding soil (sand) to enter the well. Gravel is used as a barrier between the surrounding soil outside of the casing and the water entering the casing. A gravel tube is installed to monitor the level of gravel within the well and to add additional gravel as necessary. Sounding Tube A sounding tube is a tube (pipe) that is installed into the well casing to allow for the measurement of groundwater levels within a well. There are several methods of measuring the depth to groundwater, which include automatic measuring devices and manual methods. The simplest means of measuring the level of groundwater below ground surface (bgs) is with a cable lowered into a sounding tube, which has markings identifying distances in various increments (inches.) The cable is connected to a light or signal and when the bottom of the cable touches the water a sound or light signal will occur. Other means of measuring the depth to groundwater include electronic transducers and airline water level measuring. Airline tube measuring is accomplished by lowering a tube into the well, supplying air pressure to the tube and measuring the pressure with a gauge. Each pound per square inch of pressure equates to 2.31 feet. In addition to measuring groundwater levels, sounding tubes can be used to add chlorine or other disinfecting or treatment chemical agents into a well. Pump Pedestal The well casing vent, gravel tube, and sounding tube are encased within a concrete pump pedestal. A pump pedestal is designed to support the entire weight of the pumping unit. The concrete should be continuously poured with steel reinforcement in order to minimize cracks and breaches in the concrete. Fractures in the concrete could expose the inside of the well to surface water and other potential contaminants. A pump pedestal must also be a minimum of 18 inches above the finished elevations of the well pad. Pump Motor Base At the point where the motor rests on the pedestal, it must have a watertight seal. This seal is commonly provided by a neoprene rubber gasket. This establishes a barrier seal between the motor base and the concrete pump pedestal. Drain Line (Discharge to waste) These are only some of the more common above-ground components of a well. There are other features, but they will not be covered in this text. The following items are a list of some below-ground features of a well. Casing A casing is an impervious durable pipe placed in a well to prevent the walls of the surrounding soil from caving in on the well. A casing is also designed to seal off water from draining into a well from specific depths. Conductor casing When a well is drilled the upper portions of the surrounding soil tends to be loose and a conductor casing is used to support the drilling operations. It is a tubular structure between the drilled hole and the inner casing completed in the upper portion of a well. Annular seal Another means to prevent surface water from entering a well is the annular seal. An annular or sanitary seal is a cement grout installed between the well casing and the conductor casing, the space between the conductor casing and the borehole, or the space between the well casing and the borehole depending on the well. This seal also protects the well casing or conductor casing against exterior corrosion. Three (3) types of grout are used; neat cement grout, sand-cement grout, and bentonite clay. Intake section Water enters a well through an intake section. This portion of a well is designed to allow water to enter the well casing and prevent the surrounding soil from entering. The following items are general characteristics of a properly designed intake section: • Non clogging slots/screen • Resistant to corrosion • Sufficient collapse strength • Resistant to encrusting • Low head loss • Prevent sand from entering There are five (5) common types of intake sections of a well. These include: • Well screens • Mill-cut slots • Formed louvers • Torch-cut/chisel-cut slots • Mechanical slots Well screens are generally constructed of stainless steel, monel metal, special nickel alloy, silicon red brass, red brass, special alloy steel, and plastic. They are broken into three (3) main categories which include continuous slots, bar, and wire-wound screens. Mill-cut slots are commonly made of the same type and diameter as the casing. The openings are machine milled (cut) into the wall of the casing pipe parallel to the axis of the casing and uniformly spaced around the casing pipe. Formed louvers are machined horizontal to the axis of the casing with the openings facing downward. They are shaped to create an upward flow as the water enters a well and they are placed together in vertical rows. Torch-cut slots are not very common. They are relatively simple to create, but very difficult to control the size of the openings. This has a tendency to produce excessive quantities of sand. Mechanical slots are usually slotted after the well has been drilled. The openings are made opposite the water-bearing formations by means of a casing perforator tool lowered into the well and activated from the drill rig. One main downside of this process is the openings cannot be closely spaced. Well Drilling In order for water to be extracted from an aquifer, a well must be constructed (drilled). There are several methods of well drilling. The more common methods include: • Cable Tool • California Stovepipe • Direct Rotary • Reverse Circulation Rotary • Air Rotary Cable Tool Method The cable tool method of drilling wells is also referred to as the “percussion” method. This method involves the lifting and dropping of a heavy string of drilling tools into the borehole. The cable tools can weigh in excess of one (1) ton and the drill bit breaks or crushes consolidated rock into smaller and smaller fragments. In unconsolidated rock the bit loosens and breaks apart the material. The reciprocating action of the tools mixes the crushed and loosened materials with water to form a slurry at the bottom of the borehole. The slurry needs to be removed and is done so with the use of a sand pump or bailer. The cable tool drilling equipment consists of five (5) components; drill bit, drill stem, drilling jars, swivel socket, and cable. California Stovepipe This method is similar to the cable tool method. The difference is a heavy bailer is used as both a drill bit and bailer. This heavy bailer is referred to as a mud scow. The stovepipe casing is what also distinguishes this method from others. It uses laminated steel in short lengths providing added strength, as opposed to using standard steel. Hydraulics jacks are used to force the casing downward as opposed to driving the casing with impact tools. Once the casing is at the desired depth, a perforator is used to puncture holes in the pipe opposite the water-bearing formation. Direct Rotary As drilling technologies progressed, the desire for faster drilling speeds and greater drilling depths increased. The direct rotary method uses a rotating drill bit. The cuttings are removed by the continuous circulation motion of a drilling fluid as the bit penetrates the formation. The bit is attached to a lower end of a string drill pipe, which transmits the rotating action from the rig to the bit. The drilling fluid is pumped down through the drill pipe and out through the ports or jets in the bit. The fluid flows upward in the annular space between the hole and the drill pipe, carrying the cuttings in suspension to the surface. Reverse Circulation Rotary The reverse circulation rotary drilling method was designed to overcome limitations in borehole diameter and drilling depths. In this method, both water and air are used as the drilling fluid and the direction of the drilling rotation is reversed. As a result of this direction, the drilling fluid and the load of cuttings move upward inside the drill pipe and are discharged by the pump into a settling pit. Air Rotary In solid consolidated materials, standard drilling practices are more difficult. Therefore, an air rotary method is often employed. This process uses compressed air as the drilling fluid as opposed to drilling mud. Air is circulated through the center of the drill pipe out through ports in the drill bit. In order to break through consolidated material, pressures from 100 to 250 pounds per square inch (psi) are needed. The process of removing the cuttings requires ascending air velocities of at least 3,000 feet per minute are necessary. Shallow Wells In some areas, groundwater levels are very shallow. These are usually in areas adjacent to running riverbeds and lakes. In these areas, the surface river and lake water could be used as drinking supplies. However, surface waters require a significant amount of treatment in order to remove turbidity (sediment). This can be quite costly. One of the benefits of groundwater is the natural filtration the geological formations provide. In these areas, shallow collector wells are often used. Trenches are dug around ten (10) to twenty (20) feet deep and screened pipe is laid horizontally to the river or lake bank. Depending on the type of surrounding soil, these pipes are often radially driven. Caissons (watertight retaining structures) are used to gain access to the bottom of a stream or other water body. A common shallow collector type is a Ranney. Here is an animation of a well being constructed. Well Pumps A few terms should be defined before discussing the classification and types of pumps used for wells. These terms are general terms relating to the inlet and outlet side of all pumps. Pressure is the concept of a continuous force being exerted on or against an object, while “head” is commonly used because it evaluates a pump’s capacity to do a job. For this discussion, both pressure and head will be considered interchangeable. Pressure is expressed as pounds per square inch (psi) and head expressed in feet. Suction Head, Suction Lift, and Discharge Head The inlet side of a pump is referred to as suction head or suction lift. Suction, referring to the “sucking” or pulling aspect of a fluid entering a pump. If the fluid is above the inlet side of a pump it is referred to as suction head. This is because the fluid is providing pressure to the inlet or suction side of a pump. In essence, it is helping the pump push water through the pump and to the discharge side of the pump. If the fluid being pumped is below the suction side, then the pump has to “suck” or lift the water up to the pump. This is referred to as suction lift. Discharge head refers to the outlet side of a pump, which is “pushing” the fluid out. There are two major pump classifications for wells: positive displacement and variable displacement. The common types of each include: • Piston (positive displacement) • Rotary (positive displacement) • Centrifugal (variable displacement) • Turbine (variable displacement) • Jet (variable displacement) Positive displacement well pumps deliver the same volume or flow of water against any head pressure within the operating capacity. Typical types are piston (reciprocating) pumps and screw or squeeze displacement (diaphragm) pumps. Variable displacement well pumps deliver water with the volume or flow varying inversely with the head (the greater the head, the less the volume or flow) against which they are operating. The major types are centrifugal, jet, and airlift pumps. There are various uses for each type of pump throughout the water utility industry. However, turbine pumps are predominately used for groundwater wells. Since groundwater is found at different depths below the ground, it only stands to reason there might be different types of “turbine” pumps to lift this water out of the ground. • Shallow Well Pumps – When a well is constructed in shallow aquifer systems. Shallow can be a relative term, but in this context let’s assume it is within fifty (50) feet below ground surface. Under these circumstances, a shallow well pump would be installed above a well. It would take water from the well by suction lift. The critical issue is the water level must be within the “lift” capacity of the pump • Deep Well Pumps – Since many wells are drilled deeper than fifty (50) feet, most pumps cannot “lift” the water above these depths when they are installed above a well. Therefore, deep well pumps are used. These types of turbine pumps have a series of pump bowls installed in a well with the inlet (suction) section of the pump submerged below the pumping level in a well. Since pressures can be expressed in both units of psi and feet, there needs to be a way to convert between the two. One pound per square inch equates to just over two feet. See the example below. • 1 psi = 2.31 feet (head) If a pump has a discharge head of 100 psi, how many feet does this equal? • 100 psi12.31 feet1 psi=231 feet While this text discusses aspects of water-related mathematical computations, it is advised to take specific coursework in waterworks mathematics. Measuring Groundwater Levels An important set of data associated with groundwater wells is the measurement of water below the ground surface. There are two common measurements in a groundwater well: static and pumping. The static water level within a well is the depth of water below the ground surface when a well is not running. In contrast, the pumping level is the measure below the ground surface when a well is running. The diagram below illustrates these two terms. In this diagram, there are several other important terms. Drawdown is the difference between the pumping and static water levels. This level identifies the distance the water level drops when a well is off and when it is running. Also depicted in the diagram is something referred to as the cone of depression. The water level in an aquifer is only affected by a well running within a certain area around the well. This area of “depression” pulls the water down deeper closer to the well and the further away from the well the effect is less. Hence, a “cone” shaped effect occurs. The distance from the center of a well to the farthest area where the depression effect occurs is referred to as the radius of influence. These measurements help in the analysis of the health of the underlying aquifer and the efficiency of a well. Sample Questions 1. If an airline measuring device is used to measure the depth to groundwater displays a pressure of 125 psi, what is the depth in feet? 1. 125 feet 2. 289 feet 3. 54 feet 4. None of the above 2. An unconfined aquifer is ___________. 1. More susceptible to contamination than a confined aquifer 2. Less susceptible to contamination than a confined aquifer 3. Typically deep within the earth’s crust 4. Not a common source of water for a water utility 3. A sounding tube is used ___________. 1. To hear if a motor is running correctly 2. To test the flow of a well 3. To measure the depth to groundwater within a well 4. To see if a well works properly 4. Which of the following materials is not a common well screen? 1. Stainless steel 2. Iron 3. Monel metal 4. Special nickel alloy 5. The annular seal is commonly made of ___________. 1. Plastic 2. Steel 3. Bentonite clay 4. All of the above

textbooks/workforce/Water_Systems_Technology/Water_140%3A_Water_Distribution_Operator_I_(Alvord)/1.10%3A_Wells.txt

• 1.1: Watermain Installation In this chapter, we will examine the details of watermain installation. • 1.2: Water Storage In this chapter, we will discuss the importance of water storage within distribution systems. • 1.3: Disinfection In this chapter, we will examine the process of drinking water disinfection, the benefits it provides, and the effects on drinking water quality. • 1.4: Motors In this chapter, we will examine the principles of electric motors and their operation. • 1.5: Instrumentation and Scada In this chapter, we will discuss how instrumentation and Supervisory Control and Data Acquisition Systems are used by water utilities • 1.6: Safety In this chapter, we will discuss good safe practices and emergency preparedness related to the water utility industry. • 1.7: Water Rates In this chapter, we will discuss the various sources of supply available for water utilities. • 1.8: Public Relations In this chapter, we will discuss the importance of and need for public relations. 01: Chapters Student Learning Outcomes After reading this chapter, you should be able to: • Understand the basic practices of water main installation • Evaluate the processes of backfilling and main testing • List the steps of installing a water main and placing into service • Analyze the use of maps and various types of drawings In a previous chapter, we discussed the importance and purpose of selecting specific water mains. In some instances, plastic pipe might be a better selection and other times ductile iron pipe might be useful. There are different uses for different types of pipe too. Regardless of the type of pipe selected, all pipe needs to be installed appropriately. The installation process will be discussed in this chapter. Pipe Shipment Water utilities need to order pipe from various manufacturers and sometimes the pipe needs to be shipped larger distances. The cost of shipping pipe is typically dependent on the distance the pipe is being transported, the size of the pipe, the weight of the pipe, and the quantity of the pipe being purchased. These variables will also dictate the method the pipe will be transported and will also contribute to the shipping costs. Ultimately, pipes are usually delivered to the water utility by truck. However, depending on the origin of the manufacturing of the pipe it may be transported by train or barge. Pipe Handling Once the pipe is delivered to a water utility, it should be properly inspected before it is unloaded from the truck. Even though manufacturers typically have a final inspection process prior to leaving their plant, damage can occur during transport. In addition, the wrong material or size may have been delivered by mistake. Therefore, it is important to inspect the following things prior to the pipe being unloaded: • Size of pipe and fittings • Class of pipe and fittings • Quantity of pipe and fittings • Condition of pipe and fittings Any problems observed during unloading should be noted in writing. The driver, shipping company, and manufacturer should all be notified. The unloading process is usually accomplished using some type of equipment. Often times with smaller shipments, the pipe will be strapped to wooden pallets and they can be unloaded from the truck using a forklift. However, with larger shipments or larger size pipe, heavy equipment might be needed. It is important that the pipe not dropped or placed down roughly, Pipes should not be allowed to strike other pipes, the ground or other items. Some pipes are shipped with special coatings and it is important these coatings are in good condition and not damaged. Padded forks on forklifts, rubber hooks, or slings are ways to prevent such damage. Pipe Storing Once the pipe has been unloaded from the delivery truck, it must be properly stored to prevent damage and contamination. If pipe is stored at job sites or remote locations, protection from vandalism should also be considered. Stockpiles of pipe should be built on a flat base to prevent rolling. If possible, the pipe should be stored off the ground and grouped by size and class. If all different sizes and classes are stored together, it will make it more difficult to transport the pipe to the job site when it is time for construction. It is helpful to lay the pipe by alternating the bell and spigot ends. This allows the pipe to be stored evenly. Polyvinyl chloride pipe should be stored out of direct sunlight as ultraviolet radiation can damage it. Any pipe that can crack or become damaged by hitting the ground, the height of the stacks of pipe should be limited to no more than three high. It is also prudent to cover the ends of the pipe during storage to prevent rodents or other animals from entering the pipe. Covering the ends also protects against contamination from dirt or other foreign objects. Sometimes covering the ends is not feasible and not critical since part of the installation process includes proper flushing and disinfecting of the pipe before being placed in service. Preparing the Pipe for Installation Pipeline projects can be small jobs requiring only a few sticks of pipe. Or, they can be extensive jobs covering several miles or more. Regardless of the size of the job, it is important to properly plan. Preparing the pipe at the job site is an important aspect of job preparation. The pipe should be placed as close to the trench as possible. This makes it easier for the pipe to be accessed and placed into the trench. String the pipe on the opposite side of the trench as the dirt (spoils) that is being excavated and should be located away from traffic and heavy equipment. The bells should be located in the direction of installation and only enough pipe should be laid out for a days work. It is also important that the pipe is protected from rolling into the trench or away from the job site. Excavation Trench excavation is the most expensive process of pipeline installation. It is important to know the location, depth, and width required for pipeline installation. A nonprofit organization called “Underground Service Alert” provides a means for anyone digging underground the opportunity to identify any other utilities or conflicts, which may exist. A toll-free number (811) should be called at least forty-eight (48) hours before any digging occurs. By calling this number, any utility in the area receives a notification that trenching will be occurring and they are then responsible to mark their utilities on the ground with an appropriately colored paint. Each different utility has a specific color as standardized by the American Public Works Association (APWA). APWA Uniform Color Code White Propose Excavation Red Electric Power Lines Orange Cable, Communication Purple Irrigation Pink Temporary Survey Marking Yellow Gas, Oil, Steam, Chemical Green Sewer, Storm Drain Blue Potable Water The local soil conditions should also be considered before trenching begins. Is there local groundwater, which can fill the trench? Is there frost or freeze issues? Is the native soil in good condition or will “fill” material need to be brought in for backfilling? Sometimes in cold climates where adequate depths are not possible, special insulation might be needed to prevent the water in the pipes from freezing. In some areas (especially in warmer climates), minimum ground cover depths are required. Some common depths are thirty-six (36) inches for water mains and eighteen (18) inches for service laterals. Whenever a pipe needs to be installed in an existing street, special consideration needs to be addressed to minimize inconveniences to the public. For example, some local cities may limit the times of construction activities. If the road is a main thoroughfare, construction may not be allowed during commute times in the mornings and evenings. Special permits for excavation may also be required. It is also very important to understand the existing and future road conditions, because these will dictate the road surface restoration requirements. Once these and other considerations are reviewed, it is important to set an excavation plan. The construction crew should review the work zone. What heavy equipment will be needed, where will the spoils and materials be placed, where will traffic control be required, and where might there be public exposure to the work zone are just a few areas crews will need to understand prior to beginning work. Since the excavation process is the most expensive part of pipeline installation, it is important to understand how much dirt is required to be removed. This is important because you don’t want to remove more dirt than is needed. Typically, the trench width should be one (1) to (2) feet greater than the outside diameter of the pipe. Trenches can be very dangerous for workers from the potential of cave-ins. There are four (4) common danger signs workers should look for to help prevent trench wall failure. These are: • Tension cracks in the ground surface parallel to the trench • Material crumbling off the walls of the trench • Settling or slumping of the ground surrounding the trench • Sudden changes in soil color, which indicates previous excavations In addition to these warning signs, certain precautions need to be in place to protect crews working in trenches. There are four (4) basic methods of preventing trench wall cave-ins. • Sloping—If there is enough room in the construction work zone, sloping the trench walls is an adequate means of preventing cave-ins. This process involves excavating the walls at an angle. The angle of repose prevents the downward forces of the soil from exceeding the soils cohesive strength. Sloping a trench is dependent on the type of soil being excavated, the amount of moisture in the soil, the surrounding conditions, and the potential of soil vibration from heavy equipment. Various angles of repose are used depending on the type of soil. Below are some common examples. • Compacted crushed rock—for every foot of depth, the trench is cut one half of a foot wide • Average soils—for every foot of depth, the trench is cut one foot wide • Compacted sharp sand—for every foot of depth, the trench is cut one and one half foot wide • Well-rounded loose sand—for every foot of depth, the trench is cut two feet wide • Shielding—This form of trench wall protection involves the use of a steel box, which is placed into the trench. It is open at the top, bottom, and on the ends, so workers can work inside of it. The protective box is pushed or towed along the trench to provide constant shield against cave-ins. It is important that the shield extends above the ground level in order to provide complete protection. These shielding boxes are also referred to as trench shields. • Shoring—Shoring is a general term used when referring to trench wall projection. It is a framework system of wood, metal, or a combination of both. This support system maintains pressure against both trench walls preventing cave-ins. It is important to install shoring from the top of the trench to the bottom of the trench. Removal of the shoring should be done in the opposite manner. This will minimize worker’s exposure of unprotected trench walls. There are three (3) main components of a shoring system. • Uprights—These are the vertical boards placed in direct contact with the face of the trench wall. The spacing of the uprights is dependent upon the soil stability. If the soil is sandy, then the uprights would be placed tightly together. • Stringers—These are the horizontal members of the shoring system to which the braces are attached. The stringers are commonly referred to as whalers. • Braces—The braces are the horizontal members, which run across the excavation to keep the uprights separated The trench bottom should be level so the pipe has support along the entire length. Sometimes a leveling board is needed to ensure the bedding is level. After the pipe is placed in the trench, the backfill material should be compacted beneath the pipe curvature. This process is known as “haunching.” It is important to make sure the pipe has proper support on all sides underground. The pipe should be set on flat firm ground. This proper bedding provides support and strength under the pipe. Bedding up to fifty (50) percent of the pipe diameter increases supporting strength by thirty-six (36) percent and proper bedding up to sixty (60) percent of the pipe diameter increases supporting strength by seventy-three (73) percent. By providing bedding over one hundred (100) percent of the pipe diameter and good compaction along the sides of the pipe increases the supporting strength by one hundred fifty (150) percent. It is also important to protect potable water mains from non-potable pipes such as sewer and storm drain. Ideally, water mains should be installed above any non-potable pipes and a one (1) foot vertical distance is commonly required. In addition, a ten (10) foot horizontal separation from sewer pipes and four (4) foot from storm drains is common. Instances where these minimum offsets cannot be achieved, special provisions and health department regulatory approval might be required. Placing water mains in a larger diameter “sleeve” and concrete encasement are some alternative solutions. Push-On Joint Installation Procedure 1. Prepare the pipe: 1. Thoroughly clean the bell socket and plain end 2. Inspect the gasket for any damage 3. Follow the manufacturer’s recommendation on whether the socket should be lubricated 4. Insert the gasket into the socket 5. In cold weather, it may be necessary to warm the gasket to facilitate insertion 6. Apply lubricant to the gasket and plain end 7. Protect the lubricant from contamination 2. Connect the pipe: 1. Be sure the plain end is properly beveled. Sharp edges can damage the gasket. 2. Keep pipes in line when making up the joint. Deflection should take place only after the joint is assembled. 3. Push the plain end into the socket 4. When pushing pipe with a backhoe or jack, use a timber header across the end of the pipe to protect it Mechanical Joint Installation Procedure 1. Prepare the pipe: 1. Clean the socket and plain the end 2. Lubricate the gasket and plain end with soapy water of an approved lubricant 3. Install the gland and rubber gasket 2. Connect the pipe: 1. Keep the pipes in line during joint assembly 2. Insert the plain end into the socket 3. Press the gasket evenly into the bell 3. Prepare the mechanical connection: 1. Push the gland toward the socket 2. Insert the bolts and hand tighten the nuts 4. Tighten the bolts: 1. Alternately tighten the nuts on opposite sides to maintain the same distance between the gland and the flange 2. Tighten the nuts to the correct torque Sample Questions 1. What is the most common cause of joint failure? 1. Having the joint too clean 2. Using unapproved soap or lubricant 3. Not having the joint completely clean 4. None of the above 2. What types of things in the recesses of the bells of pipe can cause joints to leak? 1. Sand 2. Gravel 3. Dust 4. All of the above 3. What is the piece of pipe that is cut out during tapping called? 1. Slug 2. Coupon 3. Cookie 4. Only 1 and 2 5. All of the above 4. Large-diameter pipe should be unloaded ___________. 1. By hand 2. With heavy equipment 3. By rolling it off the truck 4. Any of the above 5. What is the most expensive part of pipeline installation? 1. The material 2. The planning 3. The excavation 4. All of the above 6. What is a “story pole”? 1. A pole which is used to track the progress of the days work 2. A pole designed to improve efficiency during pipe installation 3. A pole that marks how many feet of pipe are installed each day 4. A pole with a string used to check the depth and grade of a trench

textbooks/workforce/Water_Systems_Technology/Water_141%3A_Water_Distribution_Operator_II_(Alvord)/1.01%3A_Watermain_Installation.txt

Student Learning Outcomes After reading this chapter, you should be able to: • Explain the uses and requirements of water storage • List the various types of water storage facilities • List water storage facility equipment • Describe the operations and maintenance of water storage facilities ​​​​​Water storage is an important component of a distribution system. The main purpose is to provide sufficient amounts of water to average or equalize the daily demands on the system. Storage provides increased operating conveniences by providing sources of supply throughout the day and at night when utility employees are not typically at work. It levels out pumping requirements, can decrease power costs from pumping, provides a supply of water during power outages, fire storage, and other benefits. This chapter of the text will examine water storage systems, the various types of water storage, how water storage affects water quality, and a general overview of the operation and maintenance of water storage structures. Why Water Storage Is Needed Water demand is highest in the early more and evening hours of the day. In the morning, customers are showering, using toilets, and preparing meals, which require water. In addition, most irrigation systems are in use in the early morning hours before temperatures get too hot. In the evening hours, people are returning from work and school and water demand typically increases during these times. There is low use midday and during overnight hours. Without storage, the pumping capacity would be approximately two times the average requirement. Adequate storage allows for uniform pumping. Storage also allows minimal operator involvement during non-working hours. Without storage, workers would need to be available to operate the system if unexpected increases in demand occur. A utility would require various different size pumps to match changes in demand. Frequent on-off cycling of pumps causes increased wear on pumps and motors and higher costs for electricity. Another benefit of water storage is the ability to store and supply water during emergencies and power outages. If a water utility solely relied on pumps to meet demands, anytime there is a power outage, water service would be interrupted. Having water stored in tanks allows for uninterrupted service during these times. Some distribution systems have long transmission water mains bringing the water supply into the community being served. Under these circumstances, any repairs made to these pipes requiring the water main to be isolated, would disrupt water supply to customers. Fire fighting is another critical need of community water systems. Water utilities not only need to meet operational demands, they must also meet the demands to extinguish fires. Fire fighting may account for as much as fifty (50) percent of total storage. In addition, fire-fighting demands must be met during main line breaks, power outages, and maximum customer demands. Adequate pressure must also be maintained during fire flows. Water Storage and Water Quality Water storage can help with water quality and it can also contribute to water quality problems. As part of the Safe Drinking Water Act, a set of regulations called Surface Water Treatment Rule (SWTR), requires specific times that chlorine must be in contact with the water before the water reaches the first customer. Water storage tanks can provide detention time to allow the chlorine to remain in contact with the water long enough provide the required time. Water storage can also be an area where blending multiple sources of supply can take place. If an impaired source of supply is pumped into a storage tank, unimpaired sources can also be pumped into the tank providing adequate blending of the impaired source. Water quality can also degrade in water storage tanks. While water storage tanks provide various benefits, storing too much water can lead to water quality degradation. Chlorine residuals can diminish and water can become stagnant if the water within storage tanks is not changed. Cycling tanks (allowing the level in a tank to rise and fall) can help avoid stagnation and water quality degradation. What Type and Size of Storage Is Needed? Water storage tanks come in various sizes and styles. Some of the factors to determine the type and capacity of storage in a distribution system depend on the size of the system, the topography of the distribution system, and how the distribution system is laid out (is the system spread out or concentrated in a small area). These and other criteria are used to design the water storage needs. Several terms related to water storage should be understood. • Average Day Demand (ADD)—This is the total demand for water during a period of time divided by the number of days in that time period. This is also called the average daily demand. • Maximum Day Demand (MDD)—This is the highest total demand over a 24 hour period within a given year • Peak Hour Demand (PHD)—This is the maximum demand over a one hour period within a given year • Float on the System—This is a method of operating a storage facility. Daily flow into the system is approximately equal to the average day demand. When customer demands are low, the storage facility will be filling and when demands are high the storage facility will be emptying. System hydraulics are directly related to the location of water storage facilities within a distribution system. If a water storage tank is located in close proximity to a pumping station, the head loss (pressure) to the farthest portion of the distribution system may be excessive through normal size piping. Additional transmission mains can help alleviate this type of pressure loss. If a storage tank is placed at the farthest end of a service area adequate pressure is typically received at the far ends and near the pumping stations. This type of set up avoids the need for increased main sizes. However, there must be enough capacity to the remote location to refill the tank during off-peak periods. In addition, if there is a great separation between the pumping facility and storage, lower pressures might occur in the middle of the distribution system. If possible, locating storage structures adjacent to the area with the lowest pressure is ideal. This typically provides enough available pressure to the entire service area and smaller diameter water mains can be used because flow from the tank is split into two directions. For hydraulic purposes, it is more ideal to have multiple smaller tanks instead of one larger tank. This allows for more stabilized and equal pressures throughout the distribution system. Head losses also increase whenever pumping is required over long distances and during peak demand conditions. Locating storage tanks near the center of a distribution system allows pumping stations to operate at or near average day demand conditions most of the time. Types of Water Storage Structures There are various types of water storage facilities. They are made of different types of materials and are designed in different shapes to serve various needs. While there are various storage structures storing raw water and within a treatment plant, this section only discusses storage structures found in distribution systems. The following are some of the more common water storage facilities within a distribution system: • Elevated Storage Tanks—In regions with relatively flat topography, elevated storage tanks are commonly used. They are above ground tanks supported by a steel or concrete tower or pedestal. Most are made of steel and designed to float on the system. If they are not constructed tall enough, they can overflow and provide inadequate pressures. • Hydroneumatic Storage Tanks—These tanks are used in very small systems with in adequate pressure. They are kept partially full with compressed air to provide water in excess of the pump capacity when required. These types of systems will also provide water for a limited time if a pump fails. • Standpipes—These tanks are constructed directly on the ground and have a height greater than the diameter. They are commonly used to equalize storage near a source of supply like a well field. They can also be used to provide additional fire protection. • Above Ground Storage Tanks—These are the most commonly used forms of storage tanks along the west coast of the United States. They can store large quantities of water and are located where the topography is such that they can be constructed on hillsides. The main downside is that they require a fairly large area of land. Components of Elevated and Above Ground Storage Tanks These tanks have very similar components. This section will review the major components and address any differences between the two styles of storage structures. Inlet and Outlet Pipes Elevated storage tanks generally have a common inlet and outlet pipe, while above ground storage tanks can have either common or separate inlet and outlet pipes. The purpose of these pipes is to bring water in and allow water to exit the tank. The purpose of having a separate inlet and outlet-piping configuration is to help water circulate inside the tank. The common pipe (called a riser) for an elevated storage tank typically runs up the middle of the support structure holding the tank. The inlet and outlet piping of an above-ground storage tank typically enters the tank along the bottom portion of the tank. In the separate inlet/outlet configuration, the location of the inlet and outlet connection is typically at opposite ends of the tank. Overflow Pipe Each type of tank is equipped with an overflow pipe. It is designed to allow water to exit the tank to the atmosphere in the event the water-level controls fail. They are commonly constructed to discharge into a catch basin and should never be directly connected to a sewer or storm drain. They should have a proper air gap separation from the area they are discharging into and should be screened or have a weighted flap to prevent animals from entering the pipe. Drain Connection All tanks need to be inspected periodically. While some inspections can occur with water in the tank, it is common to drain a tank for inspection, cleaning, and repairs. Water in a tank can be lowered by preventing pumps from turning on to fill the tank. However, they can only be lowered to a level the height of the outlet pipe and at no time should a tank be drained completely while in service. Once the water is brought down as far as in can while in service, a separate drain pipe can be opened to drain the rest of the water. Monitoring Devices Water storage tanks, just like other water distribution facilities are commonly equipped with monitoring devices. Details about these monitoring devices are covered in another chapter. However, the will also be discussed here briefly. One of the most important things to monitor on storage tanks is the water level. Therefore, most are equipped with either a physical site gauge mounted on the outside of the tank and/or level sensors which can transmit tank levels to remote locations. These devices are commonly furnished with high and low water level alarms. Valves In order to isolate a tank from the distribution system, a valve must be furnished along the inlet/outlet piping coming in to the tank. This valve can then be closed to take the tank out of service for maintenance and repairs. Sometimes a tank will be furnished with a valve referred to as an altitude valve. This valve is designed to close preventing the tank from overflowing. Vents Air ventilation is usually provided at the tops of tanks to allow air to escape as the tank is filling and air to enter and the level in the tank drops. These air vents must be large enough to prevent the tank from collapsing and they must be properly screened with a minimum mesh size of ¼”. Access Hatches Access inside a tank also needs to be provided. There are at least and sometimes multiple access hatches on the top of storage tanks. These allow works to enter the tank for inspection and maintenance. These hatches must be properly constructed with rims under the cover to prevent surface water runoff from getting into the tank. There are also manways at the bottom of the tank for access when a tank has been drained and taken out of service for maintenance and inspection. Ladders Access needs to be provided to the tops of tanks and inside tanks. Ladders usually provide this access. Some above ground water storage tanks use spiral staircases as opposed to ladders. Elevated storage tanks are usually equipped with three (3) different ladders. The first one runs up the leg of the tower from the ground to the balcony around the tank. The second ladder runs from the balcony to the top of the tank roof. The third ladder runs along the inside of the tank for inside access. Outside ladders should be installed six (6) to eight (8) feet off the ground or have a locked metal shield around the bottom to prevent unauthorized access. Cathodic Protection Interior tank walls are subject to corrosion, especially in the upper portions, which are not constantly submerged in water. Cathodic protection can reduce this interior corrosion in coated steel tanks. Cathodic protection reverse the flow of current that tends to dissolve iron from the tank surface causing rust and corrosion. Electrodes with a direct current (DC) are used and will corrode instead of the tank walls. In warm climates, the electrodes can be suspended from the tank roof. In cold climates, the electrodes must be submerged. The anodes can last up to ten (10) years, but should also be inspected annually. Tank Coatings Since steel can oxidize and deteriorate and since water is considered the “universal solvent”, it is important to properly coat the interior and exterior of tanks. Interior coatings must be able to withstand constant emersion in water, varying water temperatures, alternate wetting and drying periods, ice abrasion, high humidity, heat, chlorine, and mineral content in the water. Exterior coatings must endure similar conditions and maintain a good appearance. All interior coatings must be NSF approved. Operation and Maintenance The American Water Works Association recommends that all water storage structures be completely inspected every three (3) to five (5) years. Elevated and above ground storage tanks should be periodically drained, cleaned, inspected, repaired, and painted. The interior surfaces should be cleaned thoroughly with a high-pressure water jet or by sweeping and scrubbing. All dirt and debris should be removed from the tank and a complete or spot re-coating should also occur. All tanks need to be disinfected before being placed in service. This includes new construction and tanks taken out of service for maintenance. There are three (3) basic methods for disinfecting storage tanks: • The first method involves filling the entire tank with water and held at a disinfectant residual level of 10 mg/L. If the water is disinfected before entering the tank the detention time is six (6) hours and is the tank is filled and then disinfected, the detention time is twenty-four (24) hours. • The second method involves spraying the interior walls with a disinfectant solution concentration of 200 mg/L • The third method requires six (6) percent of the tank to be filled and disinfected to a residual of 50 mg/L. The tank is then completely filled and held for twenty-four (24) hours. The tank must then be sampled and analyzed for total coliform bacteria. If the results come back positive, additional disinfection is required until two (2) consecutive samples are negative. New and recoated tanks must also be sampled and analyzed for volatile organic compounds. Routine inspections should also be conducted at water storage tanks. The overflow piping, vents, hatches, ladders, and locks should be monitored frequently for damage and vandalism. Ladders should be in good condition and replaced if deemed unsafe. The roof and access points should also be checked for cracks and holes to prevent surface water leaking into the tank. Sample Questions 1. An altitude valve is used to ___________. 1. Prevent storage tanks from filling too fast 2. Prevent storage tanks from overflowing 3. Separate the inlet and out let flows 4. None of the above 2. Water storage reservoirs should be completely inspected? 1. Every year 2. Every other year 3. Every 3 to 5 years 4. Every 5 to 10 years 3. Without storage, pumping capacity would be approximately ___________. 1. Twice the average requirement 2. Three times the average requirement 3. Less than the average requirement 4. None of the above 4. Fire demand may account for as much as ___________. 1. 10% of storage 2. 25% of storage 3. 50% of storage 4. 100% of storage 5. It is recommended that storage tanks have ___________. 1. Separate inlet and outlet piping 2. Common inlet and outlet piping 3. Outlets twice as large as inlet piping 4. There are no recommendations

textbooks/workforce/Water_Systems_Technology/Water_141%3A_Water_Distribution_Operator_II_(Alvord)/1.02%3A_Water_Storage.txt

Student Learning Outcomes After reading this chapter, you should be able to: • List the various types of disinfectants • Explain the disinfection process • Describe the concepts of breakpoint chlorination and nitrification ​​​​​Disinfection is often thought of as drinking water treatment. However, it is more of a conditioning and preventative process. The process of disinfection is designed to inactivate pathogenic organisms in water with chemical oxidants or equivalent agents. This simply means the destruction (killing) of microorganisms, which poses a threat to public health. In contrast, drinking water treatment usually involves the removal of contaminants. Another term that sometimes is confused with disinfection is sterilization. Sterilization is the destruction of all organisms and not just pathogens. While sterilization may result in providing safe drinking water, it is not a necessary process and it would result in higher costs. The following chemicals can be used for the chemical disinfection of water: • Chlorine—Cl2 • Chlorine dioxide—ClO2 • Hypochlorites—OCl- • Sodium hypochlorite—NaClO • Calcium hypochlorite—Ca(ClO2) • Trichloroisocyanuric acid—C3Cl3N3O3 • Ozone—O3 • Bromine—Br2 • Iodene—I • Various bases There are other means of disinfection besides the use of chemicals. We will refer to these as physical disinfectants. The following list can be used as a physical mean to disinfect water: • Ultraviolet light—The UV rays must come in contact with each organism in order to provide disinfection • Heat—Boiling water for about five (5) minutes is usually sufficient to destroy essentially all microorganisms in the water • Ultrasonic waves—Sonic waves destroy microorganisms by vibration Chemical Disinfectants other than Chlorine Based Compounds Four (4) non-chlorine based disinfectants were listed above and while the can provide a means to disinfect and kill microorganisms in drinking water, there are drawbacks to each of them • Iodine—Using iodine as a disinfectant in drinking water can be effective, but it has a relatively high cost. In addition, iodine has potential serious physiological side effects, especially to pregnant women • Bromine—There are safety concerns and difficulties handling bromine. Direct contact with the skin can cause burns and residuals are hard to maintain. Bromine is commonly used is spas and swimming pools. • Ozone—Ozone is commonly used at drinking water treatment plants and reduces bad tastes and odors. Ozone is not usually used in distribution systems is because of the lack of a residual, high costs, and maintenance requirements. • Bases—Two of the more common bases include lime and sodium hydroxide. They leave a bitter taste and can also burn skin. Chlorine and Chlorinated Disinfectants Disinfection with chlorine and chlorinated compounds result in a disinfectant residual of free chlorine or total chlorine. Free chlorine is the amount of “free” and available chlorine to perform the disinfection process. As chlorine combines with nitrogen related compounds (as we will describe in more detail with chloramination) a combined chlorine residual occurs. This combined chlorine, along with any available free chlorine makes up a total chlorine residual. Chlorine Gas Chlorine is the most common disinfectant used in drinking water. It is in the form of a gas, provides a relatively long-lasting residual, and tends to lower the pH of the water. Chlorine gas is greenish-yellow in color and has a high coefficient of expansion. Therefore, chlorine cylinders should not be filled more than eighty-five (85) percent. Chlorine cylinders come in one hundred (100), one hundred fifty (150), and one (1) ton sizes. Only forty (40) pounds per day can be withdrawn from the smaller sized cylinders unless they are equipped with an evaporator. Cylinders are equipped with a fusible plug, which is designed to melt at temperatures between 158F and 156F to prevent the cylinder from combusting. One-ton cylinders have six (6) fusible plugs and two (2) valves to withdraw the chlorine. Chlorine gas is 2.5 times heavier than air and ventilation in chlorine rooms needs to close to the floor. Commonly, vents are twelve (12) inches above the floor. Leaks can be detected by waving an ammonia-soaked rag, which creates a white cloud. Chlorine gas has an immediately dangerous to life and health (IDLH) level of 10 ppm. Chlorine can combine with organics in drinking water created halogenated disinfection by-products. Hypochlorites of Sodium and Calcium Sodium hypochlorite comes in the form of a liquid and the chlorine concentration is commonly twelve and one half (12.5) percent. Calcium hypochlorite comes in the form of a solid as granules or tablets and is typically sixty-five (65) percent. Calcium hypochlorite is also known as high test hypochlorite (HTH). When dissolved in water hypochlorites tend to raise the pH. Hypochlorites can combine with organics in drinking water created halogenated disinfection by-products. Chlorine Dioxide Chlorine dioxide is highly effective in controlling waterborne pathogens while minimizing disinfection by-products. It is an effective means of controlling taste and odor issues. It can be expensive to use, especially in smaller quantities and can be difficult to handle. Chloramine Chloramine is a disinfection process using chlorine and ammonia together. This disinfection process is referred to as chloramination and it results in a combined or total chlorine residual. There are several reasons chloramination is used instead of chlorine alone. Chloramines are produced under three different processes; pre-ammoniation with post-chlorination, pre-chlorination with post-ammoniation, or concurrent addition of chlorine and ammonia. Concurrent addition produces the lowest disinfection by-products and pre-chlorination produces the highest disinfection by-product levels. Physical Disinfection While chemical disinfectants and chlorine specifically provide the majority of disinfection in drinking water systems, there are several other means of disinfecting water without using chemicals. These are referred to as physical means of disinfection and they include: • Ultraviolet rays—Ultraviolet (UV) light rays and inactivate microorganisms. However, the light must come in direct contact with each organism in order to inactivate. Therefore, it is not a sufficient process in drinking water systems. UV systems are commonly used with fish aquariums. • Heat—Boiling water is an efficient process to destroy microorganisms in water. “Boil Water” orders are often implemented whenever there is an issue with a drinking water system. Boiling water requires heat and time. Typically is takes approximately five (5) of boiling to destroy all microorganisms. • Ultrasonic waves—Sound waves generate cavitation bubbles in liquids resulting in intense shear forces and high stress Factors Influencing Disinfection Depending on the disinfection process, whether physical or chemical, there are things affecting the effectiveness. For example, UV light must come in direct contact with the organisms to work. We will look at six (6) variables influencing the disinfection process. The pH of the water plays a pivotal role in the effectiveness of disinfection, especially when using chlorine or chlorine related compounds. When using free chlorine with water, hypochlorus and hydrochloric acids are formed. In dilute solutions with a pH above 4, the formation of hypochlorus acid is most complete and leaves little chlorine in the solution. However, hypochlorus acid is a weak acid and poorly dissociated at pH levels below 6. The higher the pH, the greater percent of hypochlorite ion exists. Hypochlorus acid has a greater disinfection potential than hypochlorite ion. Therefore, pH plays an important role with disinfection. At a pH of approximately 7.2, 60% of dissolved chlorine exists as hypocholrus acid. At a pH of 8.5, approximately 90% of the dissolved chlorine exists as hypochlorite ions. Therefore, chlorine as a disinfectant is more efficient at pH levels around 7. Temperature also influences disinfection. The higher the temperature the more efficiently water can be disinfected. At lower temperatures, longer contact times are required. Adding larger quantities of chlorine can speed up the disinfection process. One major disadvantage of warmer waters exposed to the atmosphere is the increased dissipation rate of chlorine into the atmosphere. Excessive turbidity in water supplies will greatly reduce the efficiency of the disinfection process. Any suspended solids present in the water supply can shield microorganisms from the disinfectant. In addition, some types of suspended solids can create an increase in chlorine demand, this results in less available chlorine to react with pathogens. If some of the turbidity or if other substances in the water are in the form of organic compounds, chlorine disinfectants are greatly reduced. In addition, unwanted by-products can be formed, including trihalomethanes and halo acetic acids. The overall effect is a reduction in the overall chemical available for disinfection. Various other non-organic reducing agents can also impact the disinfection process. The demand for chlorine for all reducing agents must be satisfied before chlorine becomes available for disinfection. Inorganic reducing agents impacting chlorine disinfection include, but are not limited to hydrogen sulfide, ferrous ions, manganous ions, and nitrite ions. Chloramination vs. Chlorination Both chemicals are widely used to disinfect drinking water. Each has its benefits and drawbacks. As previously described, Chloramination results in total chlorine residual and chlorine creates a free chlorine residual. Both free and total are efficient with inactivating/killing microorganisms, including heterotrophic plate count bacteria and pathogenic organisms. They both can penetrate biofilm and reduce coliform regrowth. While free chlorine is a stronger oxidizer, chloramines provide a longer-lasting residual. At the correct ratio between chlorine and ammonia, taste and odor problems can be controlled. If water contains organic compounds, free chlorine can be combined with these compounds creating disinfection by-products, such as trihalomethane and halo acetic acid compounds. Chloramines reduce this disinfection by-product formation. Breakpoint Chlorination As chlorine is initially added to water, reducing compounds are destroyed. Both organic and inorganic reducing agents contribute to this first stage of disinfection. As a result, no chlorine residual is present. Understanding this is critical, but it is also counter-intuitive. As you add chlorine no chlorine residual is detected. More chlorine must be continually added. The next stage of breakpoint chlorination is the formation of chloroganics and chloramines. At this point, a residual begins to be detected. As the chloroganics and chloramines start to be destroyed, the residual starts to decrease. Once all the chlororganics and chloramines are completely destroyed, breakpoint is hit and all the chlorine demand is satisfied. At this point, any chlorine added is directly proportional to the chlorine residual measured. If disinfecting with chloramines, an ideal chlorine to ammonia ratio is 5:1. This means for every part of ammonia added, there should be five parts of chlorine. At this point, the highest total chlorine residual is realized and taste and odor issues are minimized. Lower chlorine to ammonia ratios result in free available ammonia. This creates a potential food source for microorganisms and results in a decreased disinfectant residual. This results in a condition referred to as nitrification. Therefore, it is important to monitor for nitrogen related components to control this condition. If the chlorine to ammonia ratio increases, the disinfectant residual also decreases and unwanted taste and odor compounds increase. If a free chlorine residual is desired and ammonia is not added along with chlorine, then chlorine needs to be continually added until breakpoint is reached. Nitrification Nitrification is an aerobic process in which bacteria reduce ammonia and organic nitrogen into nitrite and then nitrate. Nitrite rapidly reduces free chlorine and can also interfere with the measurement of a free chlorine residual. This results in a loss of total chlorine and ammonia and an increase in heterotrophic plate count bacteria. Higher temperatures and longer detention times in storage facilities increase the potential for nitrification. Water utilities using chloramination as a disinfection practice, usually have a nitrification monitoring plan. This plan would specify and describe steps the utility will take to monitor, prevent, and reduce the affects associated with nitrification. For example, the plan would specify when increased monitoring would be required. It would specify the constituents, which would need to be monitored. It would also describe maintenance activities within the distribution system such as a proactive flushing program to help distribute the chlorine residual and also remove stagnant water. Another example would be to properly cycle the water within storage tanks to prevent or reduce stratification, higher temperatures, and stagnant water. Constituents routinely monitored in systems using chloramines include ammonia, total and free chlorine, nitrite, and heterotrophic plate count bacteria. A reactive approach, which is commonly used by water utilities, is a process referred to as “batch” chlorination. Batch chlorination is the process of adding chlorine to water storage facilities when residuals become too low and/or when nitrification compounds are present. Conclusion There are a variety of methods and chemicals, which can be used to disinfect drinking water, with chlorine and chlorine related compounds being the most common. The disinfection process is critical in making sure drinking water is safe to drink by eliminating pathogenic microorganisms from the water supply. It is important to disinfect source water supplies and it is important to maintain detectable chlorine residuals within the distribution system. There are side effects related to the disinfection process including taste and odor issues and the potential formation of unwanted disinfection by-products. Therefore it is important to have adequate monitoring programs and to make sure the appropriate disinfectant is used. Sample Questions 1. The IDLH of chlorine is ___________. 1. 5 ppm 2. 10 ppm 3. 20 ppm 4. 100 ppm 2. A 1,000 ton gas chlorine cylinder has ___________. 1. 6 valves and 2 fusible plugs 2. 2 valves and 6 fusible plugs 3. 4 valves and 2 fusible plugs 4. 4 fusible plugs and 2 valves 3. Gas chlorine ___________. 1. Lowers the pH 2. Raises the pH 3. Keeps the pH neutral 4. None of the above 4. HTH stands for ___________. 1. High Tolerant Hypochlorite 2. Hypochlorite Total Hypochlorate 3. High Test Hypochlorite 4. High Total Hypochlorite 5. After “breakpoint,” ___________. 1. All chlorine added is free 2. All chlorine added is combined 3. Chlorine is not detectable 4. Chlorine is a weak disinfectant 6. Chloramines are ___________. 1. A combination of Clorox and ammonia 2. A combination of amino acids and chlorine 3. A combination of chlorine and ammonia 4. Bad because they create high levels of disinfection byproducts 7. Chlorine leaks are best detected with ___________. 1. A chlorine gas detector 2. A rag soaked with DPD 3. A rag soaked with ammonia 4. Your nose 8. Fusible plugs are designed to melt between ___________. 1. 155°F and 165°F 2. 168°F and 175°F 3. 158°F and 165°F 4. <150°F 9. A 150 lb chlorine cylinder is designed to provide 40 ppd of chlorine unless it has a(n) ___________. 1. Evaporator 2. Chiller 3. Extra fusible plug 4. They can never deliver more than 40 ppd 10. Which of the following has no effect on the disinfection process? 1. Turbidity 2. Temperature 3. pH 4. They all affect disinfection

textbooks/workforce/Water_Systems_Technology/Water_141%3A_Water_Distribution_Operator_II_(Alvord)/1.03%3A_Disinfection.txt

Student Learning Outcomes After reading this chapter, you should be able to: • List the various types of electric motors • Describe the construction of electric motors • Explain motor control equipment • Identify the types of motor maintenance Motors In order to pump water throughout a distribution system, a motor is needed to run the pump. Motors and engines are an integral part of moving water from the source to the customer. Almost all electrical motors used by water utilities to operate pumps are powered by alternating current (AC). AC flows in one direction and then the other. The current strength rises from zero to a maximum, returns to zero, and then falls and rises in the opposite direction. This sequence is called a cycle. The frequency of AC is the number of cycles that are completed in one second. For example, 60 hertz (Hz) is equivalent to 60 cycles per second. The number of peaks per cycle equals the phase power. Larger motors are usually powered by three-phase power. Electric motors are available in a wide range of types, speeds, and power capabilities. Smooth power output and high starting torque is suited for direct connection to centrifugal pumps. While most motors used in the water industry, internal combustion engines are used and have their place of function. Internal combustion engines are primarily used for standby service during emergencies or when there are power outages. Motor Definitions As with most things, there are certain terms, phrases, and words associated with motors. Therefore, this section will handle several definitions, which will help in the overall understanding as we progress through this chapter. • Horsepower (hp) is the unit of measure of power for electric motors. A Scottish engineer adopted the term by the name of James Watt. Watt compared the output of steam engines with the power of horses. • Watt is the standard unit of measure of power. One watt is equivalent to one joule per second. It is used to quantify the rate of energy transfer. The conversion between watts and horsepower is shown below: • 0.746 watt = 1 hp • Volt is a measurement of electrical pressure. It is similar to pounds per square inch of pressure in water. Common voltages are 110/120 and 220/240 volts for lighting and operation of small motors. Large motors require voltages of 440/480 or higher. • Ampere is the unit used to measure the flow electrical current • Ohm is a measure of electrical resistance or impedance. Electrical pressure drops due to resistance. • Stator is the stationary part of a motor. It usually consists of a steel core with slots in which insulated coils of copper or aluminum winding are placed. • Rotor is the rotating part of the motor. It consists of a steel core with copper or aluminum windings. The rotor is located on the motor shaft within the stator and is separated from it by only a small air gap. There are other terms associated with motors, which will be discussed later in this chapter. How a Motor Works As previously mentioned, motors are found throughout the water utility industry. However, there are motors everywhere in our day to day lives. There are motors in computers, hairdryers use a motor, fans, appliances, toys and so many other things use motors. When an electrical current starts to move along a wire, it creates a magnetic field around it. This magnetic field can cause movement, which can propel a motor. The link between electricity, magnetism, and movement is the basic science behind an electric motor. The attracting and repelling forces of a magnet within a motor are what create the rotational motion. One pole of the magnet is designated as north and the other south. A current passing through a wire wrapped around a wire rod is called an electromagnet. A simple motor is formed when a rotating magnet is placed near an electromagnet. When AC power is connected, the current is passed through the electromagnet (stator) creates a magnetic pole that attracts the unlike pole of the other magnet (rotor). Reversing the current changes the pole and the rotor spins and rotates the shaft. The magnetic field in the stator induces a current in the rotor, which then rotates, turning the motor and pump shafts. The speed at which the magnetic field rotates is called the motor’s synchronous speed. This speed is expressed as revolutions per minute (rpm). A frequency of 60 Hz has a maximum synchronous speed of 3,600 rpm or 60 revolutions per second. Remember, in 60 Hz, there are 60 cycles per second. The 60 cycles multiplied by the 60 revolutions equals 3,600 rpm. Motors can run at fractions of 3,600 rpm by increasing the number of poles in the stator. For example, a four-pole motor has a synchronous speed of 1,800 rpm and a six-pole has a synchronous speed of 1,200 rpm. Motors may also run at their synchronous speed or slightly lower. More electrical current is needed to start motors than there is needed to keep the motor running. The motor starting current (locked-rotor current) is the current drawn by the motor the instant the motor is connected to the power supply system. The locked-rotor current is often five to ten times the normal full load current. The current starts out at its maximum value and then decreases to the motor’s ordinary current draw as the motor reaches full speed. Single Phase Motors Single-phase motors operate in the same fashion as 3-Phase motors, except they are only run off of one phase. The instantaneous power of single-phase motors is not constant. This is because the system reaches a peak value twice in each cycle. Typically they are only used in fractional horsepower sizes, but they can be furnished up to 10 hp at 120 or 240 V. No power is required to bring these motors up to speed and they must be started by some outside device. A starting winding is usually built into the motor to provide initial high torque. As the motor comes to high speed a centrifugal switch changes connections to running winding. There are three basic types of single-phase motors: • Split-phase motors use a rotor with no windings. They have a comparatively low starting torque so a low starting current is needed. • Repulsion-induction motors are more complex and expensive than split-phase motors and require a higher starting current • Capacitor-phase motors have a high starting torque and high starting current. They are used in applications where the load can be brought up to speed very quickly and infrequent starting is required. Three-Phase Motors Three-phase motors are used when more than ½ horsepower is needed. A three-phase motor has two main parts. A rotor is the turning component and the stator is the part that turns the rotor. The rotor is also referred to as a squirrel cage. The squirrel cage consists of a circular network of bars and rings, which look similar to a cage connected to an axle. The stator within a three-phase motor consists of a ring with three pairs of coils. The coils are evenly spaced around the rotor. Each pair of coils is attached to one phase power. Since each is out of phase with each other, a rotating magnetic field is created and spins around the stator at a continuous rate. Three phase motors are operated at 230, 460, 2,300, or 4,000 V. There are three main classes of three-phase motors. • Squirrel-Cage Induction motors • Synchronous motors • Wound-Rotor Induction motors Various motors are used to operate pumps in the water industry. The table below identifies the motor type, phase, application, and provides some additional comments. Motor Type Phase Application Comments Induction (Squirrel cage rotor) Single Jet pumps, small centrifugal pumps <1 hp, requires switch Induction Squirrel Cage (split-phase) Three General centrifugal Low maintenance, single speed Phase-Wound Three Variable speed Speed adjustable Synchronous Three Used where power efficiency is critical No slip, efficient Vertical Hollow-Shaft Three Vertical Turbine Mounted on pump discharge head Submersible Three Submersible Submersible Principal Motor Components There are several components, which make up a motor. This section discusses five (5) principal components. • Frame—The frame of a motor provides protection. A frame is usually made of cast iron or steel. There are four (4) common frame types. • Open drip-proof—This frame type has openings that allow air to pass through and cool the motor. The openings are constructed so drops of liquid or solid particles will not normally interfere with motor operations. These frames are suitable for most indoor installation, but should not be used if water or chemicals will splash on the frame. • Totally Enclosed Fan-Cooled—In a totally enclosed frame, it is constructed so that outside air cannot enter the motor. Cooling is provided by a built-in fan. These frames are suitable for outside use and in moisture-laden atmospheres. • Totally Enclosed Explosion-Proof—This type of frame is constructed to withstand an explosion of gas or vapor within the motor. It also prevents the ignition of gas or vapor surrounding the motor by sparks within the motor. This type of frame should be used whenever the motor is located near an explosive atmosphere such as chemical feeding areas. • Submersible—A submersible frame is designed to be totally submerged in water. It is equipped with special seals to keep the water out and retain the oil surrounding the motor. • Stator—As previously explained, the stator is the stationary part of the motor. It usually consists of a steel core with slots that are insulated coils of copper or aluminum winding. • Rotor—The rotating part of a motor is called the rotor. It is located on the motor shaft within the stator. • Bearings—In order for the motor shaft to be held in position with minimal frictional resistance, bearings are used. The rotor is in turn supported by bearings, which allows the rotor to turn. The motor housing supports the bearings. Bearings are either lubricated with oil or grease to prevent metal surfaces from wearing. • Shaft—The shaft is a rod that extends through the bearings and rotor. The rotor turns the shaft to deliver mechanical power. • Windings—The windings are wires laid in coils wrapped around a magnetic core. This forms magnetic poles when energized with electrical current. • End Bells—Motor end bells or shields are the main support for the bearings Motors are designed for a wide range of loads, environmental conditions, and mounting configurations. Many motor configurations are standardized is sizes up to 200 hp. Larger motors are not usually standardized. As motors convert electrical energy into mechanical energy, heat is generated. Therefore, motors must be designed with some type of ventilation. In external temperatures greater than 104°F, the life of a motor can be shortened. Motor Control Equipment Smaller motors are usually started by directly connecting line voltage to the motor. However, in larger motors (greater than fractional horsepower) a motor started is needed. A typical motor starter includes a main disconnect switch, fuses or circuit breakers, temperature monitors, and a means for operating the motor remotely. The functions of motor control fall into two main categories. Much of the functions of motor control are for the protection of the motor and associated feeder cables. The other function determines when and how a motor operates. There are full voltage and reduce voltage motor controllers. Full voltage controllers use the full line voltage from the electrical source to start the motor. The starting current is drawn directly from the power line. In a reduced voltage controller the starting current of the motor is too high and may damage the electrical system. The controller uses a reduced voltage and current to start the pump motor. Motor control systems are either automatic or manual. Manual systems are usually less expensive and require employee labor to operate. These types of control systems are generally located in a central control room. Automatic controllers are commonly operated remotely and reduce the need for manual operation. Either type of control system should be included with high and low-level alarms as an early warning system. In order to prevent or reduce the likelihood of motor failure, motor protection equipment is often used. Thermal overload relays on starters prevent a motor from burning out if abnormal operating conditions increase the load beyond the design capacity. Fuses and circuit breakers are placed in the main power wiring of a motor to protect against short circuits. The fuses or circuits fail and shut down the motor. Overcurrent or overload relays are used to sense current surges in the power supply. In the event of a power surge, these relays disconnect the motor from the power supply. In areas where lightning may occur, lightning arresters are used to prevent damage from high voltage surges. Voltage relays are frequently used to detect a loss of power and to initiate a switchover to an alternate power source. There are a variety of other relays to protect against things such as reverse currents, phase reversals, and frequency changes. Sensors are also used to protect against overheating, increases in speed, and other operational variables, which are not considered normal. Motor Maintenance As with all mechanical equipment, a regularly scheduled maintenance program is prudent. General inspection and maintenance items include good housekeeping in order to keep the area around the motor clean and free of things, which can contribute to premature failure. An inspection checklist to routinely examine things such as alignment and balance of the motor, proper lubrication, adequate insulation, phase imbalance, and connections of switches and circuitry should be followed. Bearings need to be properly maintained as well. The bearing housing should be filled with oil. With new pumps, the oil should be completely replaced after the first month of operation. Then routine oil changes should occur every 6 to 12 months. In grease lubed bearings the temperature should be monitored closely, especially during the first month. Regreasing should be completed per manufacturer specifications. Proper records should also be maintained. The make, model, capacity, type, serial number, and warranty information should be kept in order to replace or repair the same or compatible motor. The installation date and name of the company that installed the motor should also be kept with all the other records of the motor. Manufacturers provide suggested inspection and maintenance schedules. It is also important to maintain records of the names and addresses of the manufacturer and local repair representatives. Results from any testing should also be kept on file. Depending on the size and type of motor, testing can vary. Some common testing parameters include, but are not limited to motor vibration and operating temperatures. Routine checking of cables and grounding is also recommended. Sample Questions 1. Volt is a measurement of electrical ___________. 1. Resistance 2. Pressure 3. Power 4. Current 2. Ampere is a measurement of electrical ___________. 1. Resistance 2. Pressure 3. Power 4. Current 3. Ohm is a measurement of electrical ___________. 1. Resistance 2. Pressure 3. Power 4. Current 4. Which of the following is not a three-phase motor? 1. Repulsion induction 2. Squirrel-cage induction 3. Synchronous 4. Wound-rotor induction 5. A four-pole motor has a synchronous speed of ___________. 1. 1,200 rpm 2. 1,800 rpm 3. 2,400 rpm 4. 3,600 rpm 6. The speed at which the magnetic field rotates is called the motor’s ___________. 1. Run speed 2. Rotation speed 3. Synchronous speed 4. Dynamic speed 7. Which of the following is a basic single-phase motor? 1. Repulsion-induction 2. Squirrel-cage induction 3. Synchronous 4. Wound-rotor induction 8. The stator is the ___________ part of the motor. 1. Rotating 2. Stationary 3. Insulating 4. Not part of a motor 9. Motors are designed for an external temp ___________. 1. less than 150F 2. less than 125F 3. less than 110F 4. less than 104F 10. PLC stands for ___________. 1. Programmable Logic Center 2. Pump Local Control 3. Programmable Logic Controller 4. Pump Local Center

textbooks/workforce/Water_Systems_Technology/Water_141%3A_Water_Distribution_Operator_II_(Alvord)/1.04%3A_Motors.txt

Student Learning Outcomes After reading this chapter, you should be able to: • Explain the differences between primary and secondary instrumentation • List the various ways water utilities use SCADA to operate a distribution system • Define the term telemetry and how it relates to a SCADA system There are many different processes that need to be monitored by water utility operators. These include, but are not limited to flow rates, meter totalizers, chemical dosages, pressures, levels, and various water quality parameters. Primary Instrumentation Primary instrumentation is an instrument used to measure process variables. Some of the more common process variables measured in a water distribution system include but are not limited to, flows, pressures, levels, chemical dosages, and temperatures. This sort of process flow measurement provides water utility operators information on the efficiency and overall operation of the system. Pump stations, groundwater wells, storage tanks, and other facilities should be monitored to ensure they are operating correctly and to help maintain the quality and quantity of the drinking water supply. Flow Sensors Measure the flow of water is an important aspect of any distribution system. Flow measurements are used to monitor flows coming into a distribution system (wells, treatment plants, and purchased water sources), flows moving through a distribution system (pump stations), and flows delivered to customers (water service). Measuring flows is important for accounting for the amount of water being purchased, pumped, and sold. Flows can also be used to help track when a piece of equipment needs to be maintained and/or replaced. Meters for measuring flows are typically differential pressure and velocity. They either transmit a read directly to a register (similar to a car’s odometer) or have a pulse or electronic output for monitoring at remote locations. Pressure Sensors Pressures on the inlet or suction side of a pump and pressures on the outlet or discharge side of a pump are important parameters to track. Too high or too low of pressure can cause problems with pumping equipment and within a distribution system. Pressure sensors can provide direct-read outputs or provide electronic pulses, which can transmit readings to remote locations. There are four common pressure sensors: • Strain gauge—This is the most widely used pressure gauge in modern instrumentation. It consists of a section of wire fastened to a diaphragm. The diaphragm moves changing the resistance of the wire. This changing resistance can be measured and transmitted by electrical circuits. • Bellows sensor—A bellows sensor uses flexible copper that can expand and contract with varying pressures. This is a direct reading pressure gauge. • Helical sensor—A spiral wound tubular element that coils and uncoils with changes in pressure is a helical sensor. This is a direct reading pressure gauge. • Bourdon tube—This is a semicircular tube with an elliptical cross-section that tends to assume a circular cross-sectional shape with changes in pressure. This is a direct reading pressure gauge. Level Sensors Water levels in groundwater wells and water storage tanks are commonly measured. The depth to groundwater is important to ensure the groundwater table is not drawn down too low and it also indicates when the water level drops below the bowls within a well. At this point, a well should be shut off. Water levels in storage tanks are also important to measure. Water storage tanks provide millions of gallons of water to consumers and it is critical that storage tanks do not overflow or run empty. • Float mechanisms—A simple and inexpensive type of liquid level measuring device is a float that rides on the surface and drives a transducer through an arm or cable. • Diaphragm element—This type of level sensor operates on the principle that the confined air in a tube compresses in relation to the head of water above the diaphragm. The change in pressure sensed is then related to a change in the head of water. • Bubble tube—A bubble tube provides a constant flow of air in a tube, which is suspended in the water. The pressure required to discharge air from the tube is proportional to the head of water above the bottom of the tube. Bubbler tubes are not very common and are being replaced with newer electronic equipment. Direct Electronic Sensors Probes, variable resistance devices, and ultrasonic sensors are also being used to measure levels. A probe can be suspended in the water and has an electronic circuit that detects a change in capacitance between the probe and water. It then electronically converts this information into water depth. A wound resistor inside a semi-flexible envelope makes up a variable-resistance level sensor. As the water level rises, a portion of the resistor element temporarily shorts out and changes the resistance of the sensor. This resistance is converted to a level output signal. Transducers are common water level measuring devices, which translate the head of water over the unit into a signal (typically 4-20mA), which is then converted to feet of head or pressure. Temperature Sensors There are two main types of temperature measuring devices used in water, they are thermocouples and thermistors. A thermocouple uses two wires made of different materials, which are joined at two points. One wire is referred to as the sensing point and the other the reference junction. Temperature changes between the two points causes a voltage to be generated, which can then be read directly or transmitted. A thermistor uses a semiconductive material, such as cobalt oxide, which is compressed into a desired shape from the powder form and then it is heat-treated to form crystals to which the wires are attached. Temperature changes are reflected with a corresponding change in resistance through the wires. Primary instrumentation provide real-time measurements of the condition of various pieces of equipment. Some of this information can be used for planning and scheduling routine maintenance and also can be used to indicate when something is out of the norm. These instruments are composed of a sensor, which responds to a physical condition being measured and an indicator, which converts the signal into a display on an indicator. Equipment Sensors Several parameters are monitored for different pieces of equipment in a distribution system. Electrical sensors are used to monitor voltage (volts), current (amps), resistance (ohms), and power (watts). A D’Arsonval meter is used to measure volts, amperes, and ohms on equipment. It is a current sensing device where an electromagnetic core is suspended between the poles of a permanent magnet. While these types of sensors have been used over the years, digital sensors, which indicate values directly, are more commonly found in the industry nowadays. The status of equipment is an important parameter to monitor. Common equipment status monitors include, but are not limited to vibration, position, speed, and torque sensors. Any time equipment turns on, off, or simply just runs, vibration occur. This is normal when the components within the equipment are in good condition and the flow of energy is smooth. However, as components age and begin to wear, vibration can increase. A vibration sensor, especially in locations where daily visual inspections are not possible, can be connected to the power circuit and shutdown the equipment if vibration exceeds a specified value. Similar sensors measuring speed, torque, position, and various other parameters can also be used to monitor equipment and help protect against excessive damage by shutting down equipment at specified set points. Process Analyzers In addition to sensors used to monitor the status of equipment, various other processes are commonly monitored within the water utility industry. Measuring water quality is important and common. While measuring water quality parameters in drinking water treatment plants is routine, there are several water quality parameters monitored within distribution systems. One of the most common water quality parameters measured in distribution systems is the disinfectant residual. Chlorine or chloramines are chemicals used to make sure the biological integrity of drinking water is maintained. Chlorine and chloramine residual analyzers are commonly used to measure the water quality on sources of supply such as groundwater wells and purchased water sources. The measurements can trigger alarms or can be automatically adjusted if the measured parameter falls outside predetermined set points. Secondary Instrumentation Secondary instrumentation converts signals from sensors and primary instrumentation. There are several ways instrumentation receives and transmits (indicates) parameters. There are a variety of ways including, but not limited to direct-reading indicators, which express values such as gallons per minute (gpm) for flows, volts from motors, and pressures expressed in pounds per square inch. Some receivers and indicators collect and record data. Charts are sometimes used to express the values such as the strip chart shown below. Other recorders display total accumulated values or some combination of data collection and expression. On analog devices, the values will range smoothly from the minimum and maximum values. They are generally easier to read the relative position of the value being displayed throughout the entire range. If values fall between the scaled values on the display they can easily be estimated. On digital devices, the accuracy tends to be better than analog systems and they are very easy to read. The values are typically decimal numbers on mechanical or electronic displays. However, estimating the exact value when the reading falls between divisions on the display is difficult. When sensors and the indicators are not located in the same area, some type of equipment is needed to send the signal from the sensor to the indicator. In these instances, telemetry is often used. Early telemetry systems used audio tones or electrical pulses. Digital systems are common and se a binary code to transmit signals. A sensor signal feeds into a transmitter, which then generates a series of on-off pulses. The number of on-off pulses represents a number. For example, the pulse sequence of off-on-off-on represents the number five (5). The transmitting device in a digital system is referred to as a remote terminal unit (RTU) and the receiver is called a control terminal unit (CTU). Whenever multiple signals need to be sent from more than one sensor over the same transmission line is needed, there are several employable methods. Tone-frequency sends signals over one wire or radio signal by having tone-frequency generators in the transmitter. Each parameter is sent at a different frequency. There are filters within the receiver, which sort out the signals and send them to the proper indicator. An example of this is a single voice grade telephone line. As many as twenty-one (21) frequencies can be sent over these types of systems. Scanning equipment is used to transmit the value of several parameters one at a time in a specified sequence. The receiver decodes the signals and displays each one in a specific turn. Scanning equipment can also be combined with tone-frequency to allow even more signals over a single transmission line. Polling is a system used where each instrument has its own unique address. A system controller sends out a message requesting a specific piece of equipment to transmit its data. Duplexing is the last process of transmitting signals we will discuss. There are three (3) types of duplexing systems: full-duplex, half-duplex, and simplex. • In full-duplex systems, the signals can pass in both directions at the same time • Half-duplex systems only allow signals to pass one direction at a time • A simplex system only allows signals to pass in one direction Control Systems The idea of instrumentation and control systems is to obtain the ability to make changes or corrections in the parameters being measured. Yes, it is very valuable to know what a chlorine residual is at a groundwater well, but if you need to visit the location to make actual changes based on the signals being received from a sensor then valuable time can be lost. Therefore, control systems are extremely useful. A control system allows for adjustments to be made based on the data being transmitted and received. Control systems can be broken down into four (4) main types of systems. • Direct Manual—A direct manual system, is the simplest and least complicated control system. Components are controlled by an operator that must physically visit each location to make a change. For example, if a signal is transmitted that requires a system to be turned off, in a direct manual control system, an operator must drive out to the location and manually turn the component off. This type of system has a low initial cost and has little complicated equipment to maintain. However, it does require labor and operator expertise and judgment. • Remote Manual—In a remote manual control system, an operator can make adjustments to systems and components from a remote location. This type of system still requires operator expertise and judgment, but it requires less physical labor. An example of this type of control system could be when a pump needs to be turned on or off. Instead of requiring an operator to physically visit a location to perform this task, it can be controlled remotely from a control room or some remote location. • Semiautomatic—This type of control system combines manual control from a remote location (control room) with automatic control of specific pieces of equipment. An example of this could be a circuit breaker. A breaker will disconnect automatically in response to an overload, but then it must be reset manually. This “resetting” can be remotely or at the facility. • Automatic—Full automatic control is when equipment can turn on and off or adjust their operation in response to signals from sensors and analytical instruments. There are two general modes of automatic controls: on-off differential and proportional. • On-Off Differential control systems turn equipment either full on or off in response to a signal. The rate of the equipment would need to be adjusted manually. • Proportional control systems adjust variables automatically. Proportional control systems can be broken down into three (3) main types. • Feedforward proportional control measures a variable such as chlorine dosage. The flow of water is being measured and the faster (or more) water flows through a meter, the chlorine feed system increases the amount of chlorine. This type of system is useful, but it cannot account for varying chlorine demand. • Feedback proportional control measures the output of a process and will then react to adjust the operation of the piece of equipment. This type of system is also referred to as a “closed-loop” control system because it continuously self corrects. These systems can be troublesome if there are wide variations in the water flow rate. • Combined control systems adjust in response to changes in the flow rate, but an analyzer monitoring the chlorine dosage makes minor adjustments in the feed rate of the chemical to maintain the selected residual being measured in the finished water. Supervisory Control and Data Acquisition The processes discussed in this chapter are wrapped up together into a Supervisory Control and Data Acquisition (SCADA) system. SCADA a system used in a variety of industries including drinking water treatment and distribution systems. There are field devices (primary instrumentation) such as sensors, which read various parameters, sending signals, which are received and transmitted (secondary instrumentation) through telemetry, to a centralized computer system. This allows an operator a complete view of a distribution system to see how things are operating. A variety of components and processes are monitored in a drinking water distribution system, including but not limited to storage tank levels, pump station flow rates, pressures, groundwater well depths, and chemical feed such as disinfection systems. Here is a simple example of a how a SCADA system works in a water distribution system. A groundwater well provides water to the distribution system. So, how does this well turn on and start pumping water? Years ago, an operator would drive out to the well, open the gate to the facility, insert a key to unlock the control panel, and then turn a switch to power it on. Water would enter the distribution system through a network of pipes. If a customer turns on a faucet, water would come out. What is no one was using water when the well was turned on? The water would then flow to a water storage tank. This tank would begin to fill. What would happen if the well was not shut off? Obviously enough, the storage tank would overflow. So, how would an operator know when to shut the well off? Without some sort of computer system, signal, or alarm, the operator would need to drive to the tank and visually look at the level of water. Then, the operator would drive back down to the well site and shut off the well. This is not very complicated, but it is labor-intensive and time-consuming. Fast forward to the age of computers. A sensor could be installed in the water storage tank to monitor the level. With the help of a SCADA system, specific level set points can be programmed to tell another set of sensors when to turn on and off something like a groundwater well. This is a very simplistic example of how a SCADA system works, but it adequately explains the process of a sensor sending a signal, a computer system reading this signal, and responding with a function. A control room is typically equipped with a human-machine interface (HMI). This interface is a window into the SCADA system. It graphically displays all the facilities within a system. The tanks, pumps, sources of supply are all interconnected to make sure water is continually distributed throughout the system. The system is usually equipped with various alarms to remotely notify operators through pagers, text messaging, or some other type of remote notification. This allows the system to continually function without someone sitting at a computer twenty-four (24) hours a day, seven (7) days a week. An alarm is received by an operator and then the fully trained operator would either verify the alarm was cleared after the process returned to normal operation or inform the operator that additional tasks might be needed to fix the system. Sample Questions 1. Which of the following is used to measure pressure? 1. Volute 2. Multi-jet 3. Strain gauge 4. All of the above 2. Which of the following is used to measure low pressure? 1. Bellows sensor 2. Helical sensor 3. Bourdon tube 4. All of the above 3. Bubble tubes must be installed ___________. 1. At the top of the tank 2. In the middle of the tank 3. At the bottom of the tank 4. Anywhere in the tank 4. Which of the following temperature measuring devices uses two wires? 1. Thermometer 2. Thermister 3. Thermostat 4. Thermocouple 5. Which of the following temperature measuring devices uses cobalt oxide as a semiconductive material? 1. Thermometer 2. Thermister 3. Thermostat 4. Thermocouple 6. Which type of control would not account for varying chlorine demand? 1. Feedback proportional 2. Feedforward proportional 3. Combined 4. All of the above 7. Which of the following is the smallest measurement of power? 1. Voltage 2. Amperes 3. Ohms 4. Watts 8. Amperes is a measurement of ___________. 1. Current 2. Resistance 3. Power 4. Voltage 9. SCADA stands for ___________. 1. Self Contained Analog Digital Assembly 2. Superior Computer And Data Acquisition 3. Supervisory Computer And Digital Assembly 4. Supervisory Control And Data Acquisition 10. Which of the following allows signals to only pass in one direction? 1. Half-duplex 2. Full-duplex 3. Simplex 4. All of the above

textbooks/workforce/Water_Systems_Technology/Water_141%3A_Water_Distribution_Operator_II_(Alvord)/1.05%3A_Instrumentation_And_Scada.txt

Student Learning Outcomes After reading this chapter, you should be able to: • Describe the difference between acute and chronic health effects as they relate to safety • List the various types of safety practices of a water utility • Explain the importance of proper record keeping related to safety ​​​​​​Safety in the workplace is something that transcends all industries. Each profession has their own set of safe work practices as it pertains to their specific job functions. For example, construction workers might be exposed to excessive heat. Therefore, these employees should be given the proper training and equipment to help prevent things like heat stroke. People working on an assembly line might be exposed to repetitive motions, which can lead to things like carpal tunnel syndrome. Their employer must provide the right work conditions in order to protect against strains and conditions associated with this type of activity. Another example might be someone working on a loading dock and is required to lift heavy objects. In this case, they must receive the proper instructions on how to lift properly and provided about what to do in the case where something is too heavy to lift. These are just a few examples of safety-related items workers encounter in various industries. The water utility industry is no different. In fact, a professional water worker might be exposed to many different safety-related issues compared to employees in other industries. In addition, since many water utility operators are required to work around the public, there is an aspect of protecting the public from injuries related to the work they do. This text will attempt to analyze and address many of the safety items water workers might encounter. Various Types of Safety We will break the different types of safety into three (3) main categories. These are organizational safety, fleet safety, and public safety. Each of these categories is defined below: • Organizational Safety—This is the most universal type of safety businesses (organizations) are faced with. It is the overall prevention of injury to employees. This prevention of injury is for employees both on and off the job. You might ask why an employer should be concerned with an employee’s personal safety when they are not working. The main reason organizations should instill the value of safety for employees both on and off the job is two-fold. First, any injury can result in lost time. This means if an employee gets injured at home, they may not be able to report to work. This results in inefficiency in the workplace and sometimes results in a loss of revenue for the employer. The second reason and maybe more importantly is creating a culture where safety is a value within the organization. Valuing safe work practices both on and off the job will result in a safer work environment and less loss time and money for organizations. • Fleet Safety—Water utility workers work within a community. They are required to operate equipment and drive vehicles. This can result in traffic accidents and equipment-related accidents. Fleet safety is designed to help prevent these types of accidents. • Public Safety—Put simply, public safety is the prevention of injury to the general public. Water utilities have facilities throughout a community and it is important these facilities do not pose a safety hazard to the general public. An example of this might be something simple like a meter box lid. If the lid is missing or broken, it could present a tripping hazard to someone walking along a sidewalk. Water utility workers also work in public streets. This not only presents a safety hazard to the employee but blocking off portions of a street can lead to traffic accidents and exposes the public to potential safety hazards. Organizing a Safety Program Each utility should designate an individual responsible for safety. Unfortunately in smaller agencies this is usually someone in middle management. A full-time safety officer is important in order to have one single person looking after health and safety for the entire organization. When safety is assigned to someone with other responsibilities, safety sometimes gets overlooked. Regardless who is tasked with overseeing the program, it is important that staff, management, and the entire organization look at safety as a core value. Each individual is ultimately responsible for their own safety, but they also need the correct tools and equipment to do their job safely. A designated safety’s main responsibility is to help staff and primarily supervisors. They are not tasked with providing all the training and equipment. They are to assess safety work practices and help implement safety programs. They determine the safety needs of an organization. They plan, develop, and recommend safety plans and programs. A safety officer should evaluate the effectiveness of safety plans and programs and make adjustments and corrections as necessary. Generating safety information and conducting meetings with employees and supervisors is also a function of a safety officer. Investigating accidents and injuries is also part of the responsibility of a safety officer as well as maintain records and reports covering all aspects of the safety program. These are some of the more critical responsibilities and additional tasks may be required as necessary. Management also plays a large role in regards to safety. Without management’s “buy-in”, staff sometimes feels disenfranchised. Management needs to establish an overall safety policy for the organization. They appoint the safety officer (or coordinator) and assign responsibility for accident prevention. Management establishes goals, revises as needed, and evaluates results of the overall program. Supervisors set the patterns for safety and should lead by example. No employee likes the “do as I say, not as I do” attitude. Since supervisors have direct control over employees, they should instill safety as a core value and provide the proper tools, equipment, and safety items needed to do tasks in a safe manner. They should instruct and council staff on safe work habits and review work for compliance with the safety program and regulations. Employees are the front line workers of an organization. Therefore they are typically exposed to the majority of safety hazards. They must perform their work in accordance with the appropriate safety procedures and actively participate in the safety program. All injuries and hazards should be reported. At no time should an employee work in an unsafe manner or condition. If an employee feels a job is unsafe they are to report these findings to a supervisor. The following is an example policy safety statement: • The organization’s recognition of the need for safety in order to stimulate efficiency, improve service, build employee morale, and promote better public relations • The organization’s interest in the employee - to provide proper equipment and working conditions, and to promote safety and the expectation that the individual employee will maintain safe work practices • The fact that the human factor rather than the mechanical is most significant cause of accidents, thus emphasizing the employee’s responsibility to perform the job safely • That an essential part of the supervisor’s job is responsibility for development of safe work practices and their environment Safety Regulatory Requirements The federal Occupational Safety and Health Administration (OSHA) is responsible for assuring safe and healthful working conditions by setting and enforcing standards and by providing training, outreach, education, and assistance. OSHA is part of the United States Department of Labor. Safe work practices can eliminate and reduce suffering, injury, and death. Safe work practices also reduce lost time, medical costs, and legal judgments. Proper safe work practices save time and money for companies too. OSHA has established minimum health and safety standards that are applicable to every industry. The mandate that every employer furnish employees with a workplace that is free from recognized hazards that are likely to cause death or serious physical harm. Causes of Accidents Unsafe acts and unsafe conditions are two of the most common results in accidents and injuries. Lack of experience or improper training commonly results in unsafe acts. Some employees have an indifference to safety and can result in excess accidents and injuries. Poor work habits or cutting corners, working too fast and impatience results in unnecessary accidents and injuries. It is also important for employees to be well-rested and in good physical condition. There are usually specific condition requirements for some jobs. For example, a job requiring the operation of heavy equipment or strenuous labor may require certain licenses and regular physical fitness testing. Drug and alcohol testing may also be required for certain jobs. Impaired employees pose a danger to themselves and to other co-workers. Below are examples of unsafe acts: • Ignorance—It is not that employees are ignorant. It is when they lack the experience or training to do their job safely • Indifference—Some employees and in some instances employers are “indifferent” or do not care about safe work practices • Poor work habits—Many times employees develop bad habits if they don’t understand how to perform task correctly in the first place • Laziness—Sometimes employees do not want to or are unable to provide the required effort • Haste—Working too fast can contribute to unsafe work conditions • Poor physical condition—Employees need to have proper rest and for some tasks must be physically fit • Temper—Impatience and anger can cloud judgment and result in accidents Reading through the list above you might have thought that most if not all of these are preventable. If so, you would be right. Most unsafe acts and conditions are preventable. That is not to say all accidents can be avoided, but many can by simply avoiding the list above. Safety Training Topics One of the most important aspects of a safety program is training the workforce. Some training topics are required to be completed by employees on a routine basis. Standard training requirements are found in Occupational Safety and Health Administration (OSHA) regulations. Some safety requirements are under General Industry standards while others are specific based on the type of industry. The following safety training topics are general in nature, required throughout the water industry, and provide a high level of understanding. Hazard Communication Any industry where chemicals are used, annual training explaining the hazards associated with exposure to these chemicals in the workplace must be conducted. Employers should provide employees with training prior to initial assignment to their work area. Hazard communication (HazComm) training should identify the activities and locations of the chemicals in the workplace and the health hazards associated with exposure to the chemicals. Additional topics covered in the training include but are not limited to steps employees can take to protect themselves, labeling criteria of the chemicals. And clean up procedures. As part of hazard communication training, an inventory list of chemicals needs to be provided and available to all employees. The details of which chemicals are required to be covered in training are beyond the details provided in this text. The example we will use is one of the more common chemicals used in the water industry. Chlorine is one of the most widespread chemicals used in drinking water distribution and treatment. In addition, chlorine is hazardous to health. Several different types of chlorine related compounds are used in the disinfection of drinking water. Calcium hypochlorite is corrosive in water and can support combustion. Sodium hypochlorite is a very strong base on its own and becomes an acid in water. Operators should wear goggles and gloves when working with hypochlorites. The most common disinfectant in drinking water is chlorine, which is a greenish/yellow gas. Since chlorine gas is two and half times heavier than air, ventilation is required in chlorine rooms. The ventilation vents should be twelve (12) inches above the floor. Since chlorine is a compressed gas and stored in cylinders, it should not be filled more than eighty-five (85) percent to allow for expansion. Another safety feature of chlorine gas cylinders is a fusible plug. One (1) ton cylinders have two (2) valves for removing either gas or liquid and six (6) fusible plugs. A one hundred fifty (150) pound cylinder has one of each. Fusible plugs are designed to melt between the temperatures of one hundred fifty-eight (158) and one hundred sixty-five (165) degrees Fahrenheit. If there are chlorine leaks in a cylinder, an ammonia-soaked rag can be used to help detect the leak. By waving an ammonia-soaked rag a white cloud would appear. High levels of chlorine in the air affect respiration and the immediately dangerous to life and health (IDLH) level is 10 parts per million (ppm). This example is just one of many where chemicals are used in the workplace and employees need to be properly trained on the hazards associated with working with and around these chemicals. In 2003, the United Nations adopted the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). In 2009, OSHA published regulations to align their Hazard Communication standard (HCS) with the GHS. There are five (5) mandatory components of OSHA’s HCS, one of which includes an update to what was previously known as Material Safety Data S, which sheets. The revised standard refers to Safety Data Sheets (STS) and sixteen (16) required sections with information about each chemical. If there is no relevant information under one of the subject headings, then the SDS must clearly indicate that no applicable information is available. Personal Protective Equipment One of the sections on an SDS must reference personal protection from exposure to chemicals. In addition, personal protective equipment (PPE) has its own regulatory standards regarding training, what types of working conditions might require PPE, and how to Don, Doff, and care for PPE. Each employee is responsible to maintain their own PPE and notify their supervisor whenever it needs replacing. It is the management’s responsibility to provide the training and required PPE needed by the employees. The following PPE examples are just some common types of personal protective equipment. • Hard hats—Any time there is a potential for head injuries including low headroom working conditions or overhead items, which can fall on an employee, hard hats are required. Metal or plastic hard hats can be used, but metal hard hats should not be used where there are electrical hazards. • Gloves—If there are pinching, cutting, crushing, or other hand-related injuries, then gloves should be worn. In addition, gloves may also be required when working with or around chemicals. • Respiratory—When surrounding air contains dust, fumes, mists, or any other particulates, which can be inhaled, then respiratory protection is required. Respiratory protection can be as simple as a dust mask or as complex as a self-contained breathing apparatus. • Eye Protection—Goggles, face shields, safety glasses are all forms of eye protection. Dust and debris can cause irritation is they get into someone’s eyes. Any kind of object, including chemicals, can all cause damage to the eye. • Steel-toed boats—It is prudent to wear foot protection in any construction-related industry. Therefore, steel-toed boats are often required. • Hearing Protection—Earplugs provide ear protection from loud noises and sounds. Earmuffs can also be used to protect ears. Understanding how to don and doff PPE is an important aspect of PPE training and all employees should understand the proper way to wear the appropriate equipment. Slips Trips and Falls Sometimes, the simplest and most common hazards can result in personal injury. Slips, trips, and falls should always be avoidable. Often times, it is a matter of good housekeeping. Making sure floors and walking surfaces are clear of debris and any kind of slipping or tripping hazards. Walking areas should have slip-resistant surfaces and proper handrails should be provided on stairways, catwalks, and areas where walking can be difficult. Fall protection also needs to be provided on elevated surfaces. Back Safety Back injuries are one of the most common injuries in the workplace. Improper lifting, twisting, pulling, and pushing are all aspects of back safety. Whenever lifting something heavy, workers should always bend at the knees and keep their back straight. One person should never lift large and heavy loads. When carrying something heavy, you should always turn with your legs and not at your waist. Equipment should also be used when appropriate to help lift and/or move heavy objects. Trench Safety Trenching is a method of digging into the ground to install things such as pipes. Whenever work is done inside a trench, special precautions need to be made in order to protect workers from the possibility of a cave-in. There are specific requirements based on the depth of the trench. If trenches are shallow (less than five (5) feet) then the danger is not as great as it is with deeper trenches. However, workers can still get trapped in shallow trenches. When trenches are five (5) feet or deeper, special protection is required. This protection is referred to as shoring, shielding, or sloping. If there is enough room, then sloping is allowed. Sloping is the process of reducing the depth of a trench by removing soil and opening the width of a trench to prevent the trench walls from collapsing. Shoring and shielding is the process of using equipment placed up against trench walls. The dirt being excavated (referred to as spoils) should be placed at least two (2) feet away from the trench edge and on the side opposite of the pipe being installed. If trenches are long, then ladders should be placed within twenty-five (25) feet of workers. Another important aspect of trench safety is proper supervision. Special training must be provided to individuals overseeing trenching activities. These individuals providing supervision are referred to as a “Competent Person”. Confined Spaces A confined space is defined, as a workspace, which has limited or restricted means of entry or exit, is large enough for an employee to enter and perform work, and is not designed for continuous work or occupancy. Confined spaces are defined as “permit-required” and “non-permit required” confined spaces. In order for a confined space to be classified as a permit-required confined space, it must meet the following conditions: • Contains or has the potential to contain a hazardous atmosphere • Contains a material that has the potential for engulfing an entrant • Has an internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or by a floor that slopes downward and tapers to a smaller cross-section • Contains any other recognized serious safety or health hazard The internal atmosphere of a confined space must be tested for oxygen content, flammable gases, and vapors, potentially toxic air contaminants, hydrogen sulfide, and methane. Ventilation equipment should be used to provide acceptable air conditions. Three (3) or more workers should be involved with permit-required confined spaces. One (1) or more workers inside the confined space, one (1) worker in communication with the worker(s), and one (1) worker to respond and retrieve emergency personnel if needed. Respiratory Safety As previously mentioned, it is important to provide workers with respiratory protection if the surrounding atmosphere is not adequate for a working environment. Respiratory hazards include, but are not limited: • Dust from rock, cement, coal, and wood • Dust from toxic materials such as lead, arsenic, and asbestos • Mists and fumes from chemicals and heated materials • Vapors and gases from chemicals such as chlorine, ammonia, and carbon monoxide • Oxygen deficient environments Respiratory problems can range from very mild irritation causing coughing and wheezing, to death. Respirators can be broken down into two main types, air purifying and atmosphere supplying. Air-purifying—These types of respirators use cartridges, filters, or canisters to remove contaminants from the air. In order to remove vapors and gases, a granular porous material referred to as an absorbent needs to be used. The type of filter, cartridge, or canister is dependent on the type and amount of the airborne contaminate. For example, a particulate filter would not necessarily remove vapors or gases. Therefore the employer must identify the contaminant(s) and provide employees the proper protection against dust, fumes, mists, and solid particulate matter. Atmosphere-supplying—In certain circumstances, the surrounding atmosphere is not suitable for breathing and purifying the air may not be sufficient. Therefore, a respirator where clean air is provided should be used. A common situation where this might occur is when the surrounding atmosphere lacks adequate oxygen levels or is considered oxygen deficient. At this point, atmosphere-supplying respirators are required. There are a number of various other safety topics, which should be considered if potential hazards exist. Some of these topics include, but are not limited to hand and power tool safety, electrical, head, body, and extremity protection. Traffic Control Utility workers often work in roadways. Whenever work is performed in traffic areas, the Manual on Uniform Traffic Control Devices for Streets and Highways should be used. This manual is published by the US Department of Transportation (USDOT) and specifies approved traffic control devices and procedures. Some states have their own traffic control reference manuals and those should also be reviewed before working in the street. If improper traffic control is set up, the utility can be held liable for damage from accidents. Often times special permits, such as encroachment permits are required as well as special traffic control plans need to be submitted to the governing agency. Traffic control devices such as cones, pylons, and other systems are used to channel the flow of traffic to designated areas. There are five (5) zones within a construction worksite in roadways: • Advanced Warning Zone—This area is a warning to drivers letting them know what to expect. This advanced warning can be as simple as a single flashing light to a series of signs and notifications prior to the temporary construction work and change in the flow of traffic. • Transition Zone—Whenever the redirection of the normal flow of traffic is required, a transition area is needed. Traffic must be channelized from the normal flow to the new path in order to avoid the construction area. • Buffer Zone—While not required, it is an important area for the protection of workers. It is an area between the flow of oncoming traffic and the area where employees are working. • Work Zone—This is the area where the work is being performed. Workers and equipment are within this area. By the time traffic reaches this area, it should be completely redirected out of this zone. • Termination Zone—As with the transition zone, the termination zone is redirecting traffic. Except in this zone, traffic is being returned to its normal flow path. The taper lengths and buffer zones have specific distances in relation to traffic speed. More traffic control devices, longer taper lengths, and larger buffer zones are needed as the speed of traffic increases. Occupational Injuries All injuries in the workplace should be reported immediately. This early reporting not only helps the utility determine if the injury occurred at work and it also speeds up the process for the employee to start any type of worker’s compensation. An occupation injury is defined as any personal injury sustained by an employee during the course of work. Employees should report their injury to their supervisor or to the organization's safety representative. Utilities typically have injury report forms. These forms should be simple but informative. They should contain information from both the employee and supervisor. The employee is responsible for reporting the injury and the supervisor and safety representative are responsible for making sure the report form is completed correctly. All injuries should be investigated. Accident and injury investigations provide an opportunity for the safety professional to speak with the employee and any witnesses. It allows for feedback on the cause of the incident and give the safety professional the opportunity to provide feedback on the necessity of exercising care and caution. It also presents the opportunity to identify any unsafe work practices or conditions and allows for recommendations on workplace improvements. Safety professionals should prepare and review a variety of reports associated with workplace accidents and injuries. These include, but are not limited: • Number of lost-time injuries—any injuries resulting employees missing time from work • Number of injuries requiring first aid—first aid kits should be provided at each workplace and with workers who work in remote locations • Number of injuries requiring medical attention—any injury where an employee receives assistance from a medical professional • Number of lost time days—when employees miss work due to an injury, this is referred to as lost time There are also OSHA related performance measures safety professionals use to track and interpret the prevalence of workplace-related injuries. These include: • Incidence Rate—This is based on the number of injuries requiring more than first aid per 200,000 hours worked • Frequency Rate—This is the number of lost time accidents per million employee hours worked • Severity Rate—This is the number of days lost or charged per million employee hours worked OSHA has specific reporting requirements related to workplace injuries. Most organizations are required to maintain an OSHA Form 300 Log. This log lists all recordable workplace injury and illness. OSHA defines a recordable injury or illness as: • Any work-related fatality • Any work-related injury or illness that results in loss of consciousness, days away from work, restricted work, or transfer to another job • Any work-related injury or illness requiring medical treatment beyond first aid • Any work-related diagnosed case of cancer, chronic irreversible diseases, fractured or cracked bones or teeth, and punctured eardrums In addition to these definitions, there are also special recording criteria for work-related cases involving: needle sticks and sharps injuries; medical removal; hearing loss; and tuberculosis. In general, minor injuries and injuries requiring first aid treatment do not need to be recorded. All employers are also required to notify OSHA directly when an employee is killed on the job or suffers a work-related hospitalization, amputation, or loss of an eye. Fatalities must be reported within eight (8) hours and in-patient hospitalization, amputation, or eye loss must be reported within twenty-four (24) hours. Safety is a very important aspect for all occupations. Water utility operations are no exception. It is important for safety to be supported from the top executives all the way down throughout the organization. Ultimately, the primary person responsible for safety is…YOU! Sample Questions 1. When symptoms develop rapidly within a person it is considered ___________. 1. A chronic health effect 2. An acute health effect 3. A disease 4. Both 1 and 3 2. What is the primary responsibility of the safety officer? 1. Should be a line function 2. Should be a staff function 3. Should provide all the training 4. All of the above 3. Traffic control should be set up in the following order: 1. Buffer Zone, Transition Zone, Work Zone, Termination Zone, Advanced Warning 2. Advanced Warning, Buffer Zone, Work Zone, Transition Zone, Termination Zone 3. Advanced Warning, Transition Zone, Buffer Zone, Termination Zone, Work Zone 4. Advanced Warning, Transition Zone, Buffer Zone, Work Zone, Termination Zone 4. Fusible plugs are designed to ___________. 1. Melt, preventing combustion 2. Melt between 158°F - 165°F 3. Fuse the valve connection to the hose 4. Only 1 and 2 5. A 1-ton chlorine cylinder has ___________. 1. 2 fusible plugs and 6 valves 2. 2 valves and 6 fusible plugs 3. 1 valve and 5 fusible plugs 4. 5 valves and 1 fusible plug 6. The IDLH for chlorine gas is ___________. 1. 5 ppm 2. 10 ppm 3. 20 ppm 4. 100 ppm 7. All fatalities, serious injuries and illnesses must be reported to Cal/OSHA within ___________. 1. 8 hours 2. 16 hours 3. 24 hours 4. 48 hours 8. A chronic health effect is ___________. 1. An adverse effect developing rapidly 2. An adverse effect resulting in cancer 3. An adverse effect developing over a long period of time 4. A disease with little or no symptoms

textbooks/workforce/Water_Systems_Technology/Water_141%3A_Water_Distribution_Operator_II_(Alvord)/1.06%3A_Safety.txt

Student Learning Outcomes After reading this chapter, you should be able to: • Evaluate different rate structures • Understand why water rates are needed • Analyze water rights and utility ownership Why Are There Water Rates? Water must be sold in order for a utility to be able to treat, distribute, and deliver water. There are chemical, electrical, infrastructure, labor, and a variety of expenses a water utility must cover. In order to pay for all these expenses, they must receive revenue to cover all the costs associated with operating and maintaining a water utility. This required revenue is referred to as revenue requirements. Revenue requirements can be explained, as the total revenue required to ensure proper operations and maintenance, development, and perpetuation of a distribution system, and preservation of the utilities' financial integrity. Most of the revenue received by a water utility comes from the sale of water. However, some utilities receive supplemental revenue from renting property, merchandising, services related to other utilities, taxes, capacity, and impact fees. Utilities must properly budget based on projections of water sales and all associated expenses for proper water rates are assigned in order to generate enough revenue. Sometimes budgets and associated projections extend out multiple years. Regardless of budgetary projections, they should be reviewed annually and adjusted accordingly. Water rates studies and analysis usually accompanying any rate changes. Budget projections aid this process of rate-making. Additional studies can also include financial and budgetary planning, support for issuance of debt, and evaluation of past and future adequacy of contractual, litigation, rate proceeding or other requirements. When a utility is calculating the adequacy of revenue in order to recover costs. Budgeting may require projections into the future. Projections beyond ten (10) years tend to be quite speculative, while five (5) projections are usually considered adequate. Historical water usage and other data is used to help determine appropriate water rates. However, the data must be normalized or adjusted to reflect conditions that may not continue in the future. For example, if there will be no future growth of additional customers, the need for additional sources of supply and storage may not be needed. Below is a list of some factors affecting revenues: • Number of customers served • Customer water use • Rate changes • Non-recurring sales • Weather • Conservation • Use restrictions • Price elasticity Below is a list of factors affecting revenue requirements: • Number of customers served • Customer water use • Non-recurring sales • Weather • Conservation • Use restrictions • Inflation • Interest rates on debt • Capital financing needs • Changes to tax laws • Other changes in operating • Economic conditions There are two general approaches for projecting revenue requirements. They are cash-needs approach and utility approach. Cash-Needs Approach The cash-needs approach ensures revenues are sufficient to recover all the utility cash needs for a given projected time period. This approach simply means the total amount of revenue needed to meet cash expenditures. The cash-needs approach usually relies on debt financing. Debt indentures usually specify sufficient cash to meet cash expenditures, deposits are made to reserve account(s), and debt-service coverage requirements are met. The accounting term “cash” refers to revenues being recognized as earned when cash is received and expenses charge when cash is disbursed. The term “accrual” refers to revenues being recorded when earned and expenditures are recorded when the become liabilities for benefits received and are not dependent on what period of time they are received. The cash-needs approach is usually followed by public (government-owned) water utilities. Elected officials of public water utilities are tasked with approving water rates. Utility Approach The utility approach of projecting revenue requirements is mandated for all investor-owned (private) water utilities. This approach is also referred to as “utility basis” approach. This approach is similar to the cash-needs approach. However, the governing regulatory body assigns a “rate payer advocate”. In California, this rate payer advocate group is referred to as the Division of Rate Payer Advocate (DRA) and the governing body is the California Public Utility Commission (PUC). This approach involves measuring revenue requirements with or without concern for allocating revenue requirements among classes of customers served. This means assigning or not assigning specific revenue requirements to specific classes of customers. Revenue Requirement Components In order to determine the revenue requirements, a utility must determine all the operating expenses. In other words, what does it cost the utility to provide service. On the surface, this might seem like an easy and straightforward task. However, there are a lot of aspects to operating a water utility and it is important to capture all these expenses. The following list is not exhaustive, but it is fairly comprehensive. • Administrative costs • Salaries • Benefits • Energy costs • Chemicals • Supplies • Fuel • Equipment costs • Equipment replacements • Principal and interest payments on debt • Miscellaneous The paragraphs below will provide additional detail for some of these operating costs. Operations and Maintenance These expenses are usually based on actual expenditures and adjusted to reflect anticipated changes. Operations and maintenance (O & M) costs include employee salaries, wage, benefits, purchased power to operate pumps and equipment, purchased water from other utilities, chemicals for treatment, supplies, tools, equipment, vehicles, fuel, outside services, and general overhead. Some outside services can include, billing services, construction contractors, engineering and other consultants, other utility services. This list is not exhaustive but should provide a good general understanding of the various O & M expenses. Some utility expenses are considered fixed costs while others are referred to as variable costs. Fixed costs are the costs the utility most cover to keep the utility in operation and are independent on the amount of water the utility sells. For example, if the water utility does not experience the anticipated water demand (this could be due to water use restrictions during a drought) the amount of revenue recovered would be lower than expected. However, the utility would still need to out salaries, benefits, and administrative costs. The staffing requirements are not directly proportional to the amount of water sold. Water meters would still need to be read, infrastructure, equipment, and vehicles would also need to be maintained. These costs would be considered fixed costs. Whereas, the amount of chemicals needed to treat the water might be less if the utility is producing less water. Therefore, the cost for chemicals would be less and this would be considered a variable cost. Regardless of the type of cost, the utility would still need to recover these revenue requirements. Debt Service Sometimes utilities require large amounts of funds in order to pay for large capital improvement projects. Some of these projects consist of new sources of supply such as groundwater wells, large storage facilities, and other major infrastructure improvements. If a utility had to spend several millions of dollars in a given year and tried to collect these expenditures in the same year, water rates would be unusually high. Therefore, a utility acquires debt in order to spread out these costs over multiple years. Debt service is the annual cost to pay the debt back. It includes both principal and interest. Reserves Water utilities commonly maintain reserve accounts. Reserve accounts are savings accounts. They are usually set aside for emergencies or unexpected needs. For example, if a utility has earthquake insurance, a specific reserve account can be set aside to cover the deductible costs and start making payments to begin the immediate process for repairs to the system. Another example might be a reserve account to replace a large expensive facility if there is an unexpected failure. Capital Expenditures Water utilities will typically have normal routine replacement of existing facilities. All equipment and infrastructure have reasonably expected operating lives. For example, groundwater might last fifty (50) years. The utility would have to plan for the replacement of these facilities. Another example is the piping infrastructure. A utility might have two hundred (200) miles of underground pipelines. Let’s assume the average lifespan of this pipe is seventy-five (75) years. This would mean the utility would need to replace on average 2.7 miles or 14,256 feet a pipe per year to keep up on the replacement schedule. Capital improvement projects (CIP) would also include annual extensions and other improvements. Often times, large CIP is financed through debt, reserves, or some combination. Very rarely are large projects paid for with cash. Issuing debt or using reserve funds prevents the customers from paying 100% of the initial cost of facilities. Coverage Ratio A common measurement to help determine the financial health of a utility is the coverage ratio. This is the measure of the ability of the utility to pay the principal and interest on all loans and bonds. It is calculated by subtracting the non-debt expenses from the total revenue divided by debt service expenses. A good financial coverage ration would be above 1.0. Revenue Where does a water utility get the money to fulfill revenue requirements? There are typically three (3) classes of revenue; Operating revenues, non-operating revenues, and contributions to capital. Operating revenues include both metered and unmetered water sales. Most of the time, the sale of water is metered. This means a customer pays for the water, which flows through their meter. Sometimes, utilities sell water at a flat rate or unmetered. If a water utility sells water to another water utility they would be considered a wholesale water provider. The revenue earned from these sales are also considered operating revenue. Any fee for or charge for water service is also considered operating revenue. For example, some utilities have a monthly fee for something referred to as a “readiness to serve” charge. This means if a customer has a meter service, but does not use any water for a period of time (i.e., month) the utility would still bill the customer for the ability or readiness to serve the customer. Often times this monthly service charge is based on the size of the meter. The larger the meter the higher the monthly charge. If a water utility rents property (i.e., cellular leases) or charges for the use of the utilities operating property, these would also be considered operating revenues. Non-operating revenues is a smaller amount of revenue most utilities earn, but they still need to be taken into account. Examples of non-operating revenues include merchandising interest, dividends, sale of property, tax revenues, and various other revenues not associated with operating the utility. The last classes of revenue include funds contributed by developers and grant funds. These are considered contributions to capital. Customer Classes There are generally four (4) main classes of customers. These are identified as residential, commercial, industrial, public authority, and dedicated landscape. Residential customers consist of single and multi-family dwellings. This would include attached and detached homes, apartment buildings, condominiums, and townhomes. Commercial customers would include businesses such as restaurants, small and large businesses. Industrial customers would include manufacturing and processing establishments. Public authority would be public establishments such as schools, city, and county buildings. Dedicated landscape service connections are commonly separated from other service classes. There are also some special classes of customers. These would include wholesale service, fire-protection, and service for air conditioning and refrigeration. Wholesale service is usually defined as a situation in which water is sold to a customer at one or more major points or delivery for resale to individual retail customers within the wholesale customer’s service area. This water is typically treated before being sold and is sold to a separate municipality or water district. Fire protection service is primarily a standby service. There is a readiness to deliver relatively large quantities of water for short periods of time at any of a large number of points within a distribution system. The total quantity of water used is typically small and service costs are based on one of the following two criteria: 1. Cost of service is determined on the basis of the potential demand for water for fire fighting purposes in relationship to the total of all potential demands for water. 2. Cost of service is allocated as an incremental cost to the costs of general water service. It is based on the premise that the prime function of a water utility is to supply general water service. Air conditioning and refrigeration is water sold for use in water-cooled air conditioning and refrigeration systems. Most units now use water referred to as “make-up” water. This is water recycled within the business. Water Rates It is common practice for a water utility to provide water service to all general service customers within a given jurisdiction through a single rate schedule, comprised of a two-part rate. There are three (3) common general classes of customers and these are: • Residential—This customer class generally comprises of one and two family dwellings, usually physically separate. • Commercial—This customer class is commonly comprised of multifamily apartment buildings and nonresidential, nonindustrial business enterprises. • Industrial—This customer class represents manufacturing and processing establishments Sometimes a utility will subdivide the general classes of customers into more specific groups. Water use characteristics, service requirements, and other various reasons may set certain customer classes apart from one another. Sometimes utilities will create special classes of customers, which can include wholesale, fire-protection, irrigation, and air conditioning/refrigeration services. The jurisdictional area referred to above is the service area boundary. A governing body of each water utility determines service area boundaries. In the case of investor-owned private utilities in California, the governing body is the California Public Utilities Commission (CPUC). Within the County of Los Angeles, the governing body is the Local Agency Formation Commission (LAFCO). Commonly, a two-part water rate includes an initial charge, which generally recovers customer related and possibly some volume related costs of the utility, together with a volumetric charge to recover the remaining costs. Some utilities recover their fixed costs with a monthly charge not associated with the amount of water sold. The variable revenue requirements would then be covered by the volumetric charge for water. The volumetric charge is based on the amount (or volume) of water sold. Why would a utility have a two-part rate versus just charging water based on the actual usage of each customer? This is a common question people sometimes ask. The simple answer is because of the variability in how much water people use. What would happen if every customer only used a small quantity of water? Earlier in this text, we discussed revenue requirements. A utility must sell enough water or more importantly collect enough revenue from the sale of water, to cover all their related “requirements” to operate. If customers use too little water, then the utility would not be able to collect enough revenue, unless they charged an exorbitant amount for each unit of water. An example of this will be presented in the last chapter of this text (Waterworks Mathematics). Therefore, oftentimes, a utility will have a “fixed” charge. This fixed charge is sometimes referred to as a readiness to serve charge. This allows the utility to collect sufficient revenue to keep the utility running regardless of the amount of water sold. It commonly covers meter reading, billing, and day-to-day operational costs. Therefore, a two-part rate, one part fixed and the other part variable is commonly used. Flat Rates A fixed charge is different than a flat rate. A flat rate is something utilities sometimes use when the water supply is plentiful. It is the same charge across all customer classes and users. It is an amount, which must cover the revenue requirements of the utility, but is blind to the amount of water each customer uses. This type of rate is becoming less common, especially in California where drought often affects certain parts of the state. It is also not an even or equitable means of charging for water service. It also does not encourage water savings or conservation. Variable Rates As previously mentioned, a variable rate is based on the amount of water customers use. Therefore, the more water a customer uses the more revenue the utility collects. Conversely, if a customer uses zero units of water over the billing cycle, then the utility would collect no revenue from this particular customer. Also, as previously mentioned, fixed charges can and are oftentimes included with a variable water rate. Tiered Rates Much like variable rates, a fixed charge is usually included with tiered rates. Tiered rates are another type of variable rate structure. However, in a tiered rate the variable price increases with usage. For example, each unit of water would be sold at a specific amount up to a certain unit usage set point. Then after the designated amount, the charged amount is increased until another specific usage amount, and so on. See a simple example below. • 0 – 9 Units of Water Used = \$1.00 • 10 – 19 Units of Water Used = \$2.00 • 20 – 29 Units of Water Used = \$3.00 • 30 or More Units of Water Used = \$4.00 Tiered rates are designed to encourage water conservation. The belief is as water becomes more expensive as usage goes up, usage would be curbed. While tiered rates have been shown to contribute to conservation efforts. However, there are other issues associated with charging more for water based on customer usage. The utility must explain the reason they are charging more for quantities above specific usage amounts. There have been several lawsuits associated with the legality of tiered water rates. One such lawsuit was in 2015 between a group of San Juan Capistrano taxpayers and their local water utility. It is extremely important a utility properly explains and notifies their customers before implanting water rates, especially tiered water rates. Budget Based Rates A budget based rate structure is similar to a tiered rate structure. The difference between the two is instead of charging water purely based on the quality of water used. In a water budget based rate structure, water charges are assigned based on customer usage both indoors and outdoors. While most utilities do not measure these (indoor/outdoor) uses separately, under a budget based water rate, a certain volume is often assigned for indoor water use. In addition, a specific amount is assigned for outdoor water use (irrigation). These assigned amounts are considered a customer’s budget. The rate assigned to the budget is a standard volumetric water rate. If customer’s stay within their budget, do not use more than the allocated amount, then the rate does not change. However, if a customer uses more water than their allocation, the cost of water increases similar to a tiered structure. Another difference to a water budget rate structure compared to a standard tiered rate structure is budgets are commonly personalized for each customer. In a tiered system, all customers follow the same tiered rate, whereas budgets can be based on the specific water needs of each customer. Regardless of the rate structure, the utility must be able to adequately recover its revenue requirements with the chosen rate structure. Rates are designed for specific periods of time known as the rate schedules. Projections of expenses are compared against projections of water use and then a rate can be calculated. During a water rate study, utilities will commonly use something referred to as a test year. A test year is an annualized period for which costs are analyzed and rates are established. Utility costs for ongoing operations and maintenance of the system as well as past large capital improvements must be incorporated into the water rate. In addition, utilities need to properly account for future replacements and growth of the utility. While existing customers typically cover a large portion of these costs, some of the future expansion of a system should be and often times is paid for through fees to construction developers. These fees are referred to as facility capacity and connection fees. These fees are associated with expanding a system in order to supply water to additional customers. The concept of recovering costs and expenditures through the sale of water is a fairly simplistic concept. However, determining necessary costs and expenditures and calculating the water rate associated with recovering this money is a difficult and complex process in order to keep the customer of water reasonable to the customer, but also ensuring the utility has enough cash flow to keep operations flowing. Sample Questions 1. Budget projections beyond 10 years tend to be ___________. 1. Accurate 2. Speculative 3. Adequate 4. Both 1 and 3 2. The “Cash-Needs” approach is typically used by ___________. 1. Private utilities 2. Public utilities 3. Agencies with multiple commodities 4. All of the above 3. Which of the following is not included in O&M expenses? 1. Salaries 2. Purchased water 3. Chemicals 4. None of the above 4. Investor-owned utilities are governed by ___________. 1. An elected board of directors 2. A City Council 3. The California Public Utilities Commission 4. A Mayor 5. A periodic stated charge for utility service not based on the metered quantity of service defines ___________. 1. Firm service 2. Flat rate 3. Rate blocks 4. Standard rates 6. The annualized period for which costs are to be analyzed and rates established defines ___________. 1. Test year 2. Yearly projections 3. Annual analysis 4. None of the above 7. Connection fees are charged to ___________. 1. Create revenue for O&M expenses 2. New customers for the costs of new facilities needed to apply water 3. Help establish service area boundaries 4. All of the above

textbooks/workforce/Water_Systems_Technology/Water_141%3A_Water_Distribution_Operator_II_(Alvord)/1.07%3A_Water_Rates.txt

Student Learning Outcomes After reading this chapter, you should be able to: • Explain the importance of public relations as it pertains to public perception • Identify the key areas where communicating to the public is important • List four (4) main areas the public experiences a water utility and their workers Many times, public relations are looked at as a marketing strategy for businesses selling a product, or, perhaps a government agency disseminating information to a certain constituency or group of voters. Public relations (PR) is nothing more than the spread of information between an individual or an organization to the public. Therefore, PR is just as important for a water utility. Even though customers do not have a choice who they receive their drinking water from, it is important for a water utility to be open, transparent, and helpful to their customers. Therefore, providing good public relations is important. A water utility is in the public eye in a variety of ways. Utility vehicles are driving throughout a town performing work. Meter readers often visit customer homes to read a water meter. Every time someone turns on their faucet and the water coming out is unacceptable or when someone receives a high water bill, the water utility is often the one a customer will blame. Some areas water utility workers are exposed to the general public include, but are not limited to meter reading, operations and maintenance workers, vehicle operation, public meetings, and customer calls and complaints. These are not the only instances where customers can and interact with water utility workers. Meter Readers Meter readers have the potential of interacting with customers on a routine basis. Meters are generally located near the property boundary of customers and in some parts of the United States; they can be installed inside customer buildings. Therefore, a customer might approach an employee reading meters. Customers can be in search of specific information about the service they are receiving or perhaps they might have questions about something they heard about in the news. Regardless of what a customer might be asking, it is important for meter readers to be respectful and polite. Meter readers should maintain a neat appearance. Many utilities provide their employees with uniforms, which clearly display the utility’s name. If a meter reader is speaking with a customer they should provide some form of identification letting the customer know who they are and whom they work for. If a customer’s meter is inside a customer’s residence, a customer may be reluctant to allow them into their home without proper identification or someone who is wearing worn-out clothes, dirty, or unshaven. Meter readers should be properly trained and have a good general understanding of utility operations. However, at no time should any employee, including meters, feel responsible to answer any questions they are unfamiliar with. Sometimes meter readers will carry around brochures with frequently asked questions and they should always provide the customer with a phone number to call, in order to receive additional information. While reading meters, a meter reader should also be aware of any abnormalities with the customer’s service. If a leak is detected on the customer’s side of the service, they should attempt to contact the customer. If a customer is not home, often times a water service notice tag is left on the customer’s door. Whenever dealing with the public a meter reader should stay pleasant and polite. Operations and Maintenance Workers This group of workers does not typically have direct contact with customers. Therefore, while they should maintain a neat appearance, it is not as important as with meter readers. Sometimes when workers are working in the public right of way (i.e., streets, sidewalks, etc) a local resident may inquire about the work they are doing. While it may seem obvious to the worker, they need to remember most of the time the public is just curious. Therefore, it is important for the worker to be polite and to refrain from “smart aleck” responses. It is oftentimes best for a worker to refer the inquisitive public to the supervisor in charge of the work instead of trying to answer all the questions they might be asked. It is important for the utility to give the public proper notice whenever service is planned to be disrupted or when streets might be closed. This can be accomplished through mailers, calls, or signs placed in the work area. During planned shutdowns for repairs or new installs, door hangers are commonly used to provide the local residents notice. All work zones should be properly marked and kept safe. Safety cones, tape, and other means can be used to block public access in order to protect public safety. Work zones should also be kept as clean as possible and workers should avoid sitting or walking on private property. Customers generally do not like workers taking their breaks on their lawns. Equipment and vehicles should look clean and professional and tools should not be scattered around the worksite. After the work is complete, the workers need to leave the area in the condition (or better) as they found it. Vehicle Operation Water utility workers generally drive a significant amount throughout their day. This increases the potential for accidents and citations. Therefore, it is critical that all utility drivers need to be careful, follow all driving rules, and be extremely cautious of their surroundings. Careless driving also makes people angry. If a utility worker is driving too fast or appears to be driving carelessly, residents often take note and many times will call the utility to complain. This generally leads to a situation where it is the worker’s word versus the resident’s word. Courteous driving leaves a better impression on the public and leads to less potential issues. Utility workers should also use good judgment on where they park their vehicles. It might make a bad impression if someone sees a utility truck parked in front of the local tavern, even if the worker is actually working around the corner. Water Quality Water quality throughout the United States is highly regulated and safe to drink. However, that doesn’t mean customers like the taste, smell, and look of their water. Even if the water is considered safe to drink, if it is discolored, has an odor, and tastes odd, customers will complain. A good PR strategy for handling water quality complaints is very important in order for customers to be confident in the water they are being served. Typically, there are water quality professionals employed by a water utility to answer questions related to water quality complaints. They are trained to explain the potential causes of these unpleasant aesthetic qualities, offer suggestions to improve the quality, and offer to sample the water if necessary. Many times, the aesthetic quality of the water is a result of internal home plumbing problems, such as old galvanized plumbing. However, sometimes water can be discolored in the distribution system from flushing or other flow changes in pipes. Other times a utility might change the disinfection practices for various reasons. This can result in taste and odor issues. If the utility is aware of potential changes in water quality from distribution activities, it is advised the utility notify customers ahead of time in order to prevent a large number of complaints. In accordance with federal and state drinking water quality regulations, annual reports must be provided to customers stating the quality of water they are being served. These reports are referred to as annual water quality reports or consumer confidence reports. These reports typically list the sources of supply, results from water quality samples collected, and health effects data related to constituents found in the water supply. These reports while regulatory requirements are also public relations materials and it provides utilities another avenue for communicating with their customers. Customer Service The staff in customer service departments is the first exposure a customer has with a utility. Customers often call with questions or complaints about their service. Some customers pay their water bills in person. Customer service representatives can experience angry and hostile customers who are unhappy with the service provided by the utility. They may receive calls and complaints about high water bills, poor water quality, low or high water pressure, leaks, and a host of other issues customers might experience. These customer service representatives should be trained to be able to appropriately handle customer complaints and when to escalate complaints to their supervisors. Customer service representatives should remain calm and polite, even if a customer raises their voice and/or gets angry. This is easier said than done. However, it is important to try and diffuse conflict with customers. If a customer is aggressive with an employee of a utility getting angry will only escalate the problem. Instead, it is recommended to listen, listen, and listen. People taking the time to call a utility and complain, want to be heard. Once you have listened to the customer’s issue, offer to help. Even if there is not much you can do, the simple offer of wanting to help will go a long way. Customer service representatives need to be provided with the proper tools to be able to adequately address customer concerns. Access to customer account information is important as well as a list of staff that the representative can refer or transfer customers to. For example, if a customer is complaining or has questions about the quality of their water, there should be staff within the organization that are able to answer questions and provide answers to customers. Therefore, properly trained staff is an important aspect of public relations and good customer service. Media The general rule most water utility workers should follow when it comes to talking with anyone from the media is, don’t do it. There are too many opportunities for being misquoted and it can be embarrassing to see incorrect information in print, on the radio or television. Water utilities should have a designated media spokesperson to handle all questions and interviews from reporters. However, oftentimes, the front line workers are the first people on the scene and might be approached by reporters. If this happens, workers should give very brief and factual information about what they are doing and that is all. For example, if crews are responding to a water main break that is all the information the workers should offer. They can explain what they are doing and why they are at the location. However, they should avoid speculating as to the cause of the problem or how long they will be at the work location. They should let reporters know they are not qualified to go into more detail and that a supervisor or media representative will arrive on site soon. Larger organizations can have designated public relations departments and spokespeople, commonly public information officers. In smaller utilities, middle or upper management staff is typically the designated spokesperson. Regardless of the spokesperson they should speak in facts only and never speculate. Communication It is important for a utility to properly communicate with its customers and the community as a whole. General communication about the service provided by the utility is important to convey to customers. Informing customers about changes in their water rates, conservation information, how to pay or where to pay water bills, or things such as business hours are all important items to communicate. In addition, it is important to properly notify customers and the general public whenever there’s going to be work performed or water outages. Strategic communication planning is also important. It is important to properly plan and relay information about changes in regulations, which can affect customers, changes in water quality or service reliability, and meet the public’s expectations. There are four steps to successful communication planning. These include understanding the message, identifying the audience who will receive the communication, deciding on the type of communication, and the strategic planning of the dissemination of the communication. It is important to establish a good working relationship with the local media. Working directly with reporters and writers for local newspapers and news media who typically write and report on environmental and utility-related issues is suggested. Working with the local media provides a means to open and honest dialog and the ability to help frame the stories they cover. Public relations representatives should be accessible for comments regardless if the story is positive or negative. Access to subject matter experts should also be provided. Many times a story is about a topic involving issues of a complex nature. The subject matter experts should be available for interviews. However, they should also be able to explain complex subject matter in non-technical and understandable terms. Public Media Events Often times a utility will host a variety of public events. These events should be designed to provide valuable information and educate the participants about the event. These events can be joint events with other local agencies and organizations. They are typically intended to create public involvement and participation. It is important to properly advertise the events and host in a location with ample space. All public events should be held in locations convenient to the public, have plenty of parking, and access to restrooms. A public event is designed to create a positive and informative perception of the local community. While it is not necessary, utilities often have free items to hand out to the visiting public. If the event is a water conservation event, the utility may offer free low flow showerheads or other water-saving devices. If the event is about drinking water quality, free sample water testing kits are sometimes offered. Regardless of the event, free “trinkets” with the utilities logo or name are good ways to publicize the agency. Emergency Information No one looks forward to a crisis or emergency. However, all water utilities should be prepared to properly respond to and notify their customers in the case of one of these events. An emergency can be associated with a large water main break where traffic is disrupted and water service is lost to several customers to a major catastrophe where water service is lost to thousands of customers. Regardless of the extent of the emergency, the utility needs to be properly prepared. In addition to operational planning of how a utility will respond to water quality and operational issues, a utility needs to have proper public relations planning and preparation. Some media notifications are required by regulations. For example, if a utility has a Tier 1 water quality violation, they must notify all of their customer within twenty-four (24) hours. In these situations, it is important not to waste any time. Therefore, it is important for the public relations team to prepare ahead of time. In these situations, if the utility has developed a good working relationship with the media, disseminating information is easier. It is important to know all the media outlets in the utilities service area, including but not limited to newspapers, radio stations, and television stations. Interviews When possible, interviews should be conducted with public relations personnel or by knowledgeable staff. There are things you definitely don’t want to say during an interview and there are strategies for giving a successful interview. One common mistake by interviewees is not listening to the interviewer’s question. You should always take your time before answering a question and listen carefully to what is being asked. If the interview is live radio or television, be sure to speak clearly and try to avoid using acronyms and too technical details. An interviewee should always assume they are providing information to an uninformed audience. Keeping things to basic grade level responses can be effective. Always look at the person (reporter) interviewing you and try and not look at the camera. Whether in print, audio, or visual media, the interviewee should try and disseminate information that is factual and stands on its own merit. Sometimes interviewers paraphrase information and you want to avoid any misinterpretation. In any print media, in-depth detailed information is generally acceptable. The reader has the opportunity to reread statements if they do not understand something. However, it is still important to provide facts and not opinions. Sample Questions 1. Which one of the following is not an example where utility workers are exposed to the public? 1. Meter reading 2. Public Meetings 3. Accounting 4. Vehicle Operation 2. What would be a common mistake in a public relations interview? 1. Not listening to the interviewer's question 2. Answering a question specifically 3. Looking at the person conducting the interview 4. Disseminate factual information 3. In larger organizations, it is common to have ___________ act as the organization's public spokesperson. 1. Middle Manager 2. Public Information Officer 3. Customer Service Representative 4. Consultants 4. Operations and Maintenance workers typically have frequent contact with the public. 1. True 2. False

textbooks/workforce/Water_Systems_Technology/Water_141%3A_Water_Distribution_Operator_II_(Alvord)/1.08%3A_Public_Relations.txt