Upon completion of this unit of study, the student should be able to: 1. Identify the parts of a water distribution system.

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2 Water Supply - 1

3 UNIT OBJECTIVES Upon completion of this unit of study, the student should be able to: 1. Identify the parts of a water distribution system. 2. Identify the causes of increased resistance or friction loss in water mains. 3. Identify the types of water main valves. 4. Define the terms static pressure, normal operating pressure, residual pressure, and flow pressure. 5. Identify the differences between dry-barrel and wet-barrel hydrants. 6. Describe the conditions which reduce hydrant effectiveness. 7. Describe and demonstrate connecting a supply hose to a hydrant and operating the hydrant. 8. Identify the apparatus and equipment necessary for a water shuttle and how to set up a portable water tank and assemble equipment to transfer water between portable tanks. 9. Demonstrate the assembly and connection of drafting equipment required for drafting from a static water supply. Water Supply - 1

4 NFPA STANDARDS Successful completion of the information in this section is necessary to fulfill the requirements of the following sections of NFPA : Fire Fighter I Standard * Connect a fire department pumper to a water supply as a member of a team, given supply or intake hose, hose tools, and a fire hydrant or static water source, so that connections are tight and water flow is unobstructed. (A) Requisite Knowledge. Loading and off-loading procedures for mobile water supply apparatus; fire hydrant operation; and suitable static water supply sources, procedures, and protocol for connecting to various water sources. (B) Requisite Skills. The ability to hand lay a supply hose, connect and place hard suction hose for drafting operations, deploy portable water tanks as well as the equipment necessary to transfer water between and draft from them, make hydrant-to-pumper hose connections for forward and reverse lays, connect supply hose to a hydrant, and fully open and close the hydrant. Fire Fighter II Standard 6.5.3* Prepare a preincident survey, given forms, necessary tools, and an assignment, so that all required occupancy information is recorded, items of concern are noted, and accurate sketches or diagrams are prepared. (A) Requisite Knowledge. The sources of water supply for fire protection; the fundamentals of fire suppression and detection systems; common symbols used in diagramming construction features, utilities, hazards, and fire protection systems; departmental requirements for a preincident survey and form completion; and the importance of accurate diagrams. (B) Requisite Skills. The ability to identify the components of fire suppression and detection systems; sketch the site, buildings, and special features; detect hazards and special considerations to include in the preincident sketch; and complete all related departmental forms. 2 - Water Supply

5 I. Water Supply A. Water has always been the primary extinguishing agent for fire fighting for its: 1. Availability 2. Economy 3. Effectiveness 4. Ease of storage and transfer B. Fire fighters must have a knowledge of water supply systems and how to use these systems to supply water for fire fighting efforts II. Water Distribution Systems (Essentials p. 594) A. Public and private water supply systems typically serve large areas with numerous individual properties 1. May be a city-operated utility, a public water supply district, or a private water company 2. Several municipal water systems in Missouri have been sold to private corporations B. Sources of water supply 1. Surface water a. Rivers b. Lakes c. Reservoirs Water Supply - 3

6 2. Ground water a. Water wells b. Water-producing springs C. Means of moving water 1. Direct pumping system a. Uses pumps to take water from the primary source to the treatment process and into the distribution system b. Most direct pumping systems are found in agricultural and industrial settings c. The main disadvantage is the reliance only on pumps and electricity to operate the pumps d. Backup generators and duplicate pumps may be needed for reliability 2. Gravity system a. Uses a primary water source at a higher elevation than the distribution system b. Gravity pressure is adequate only when the primary water source is more than 100 feet higher than the highest point in the water system 3. Combination systems a. Most communities use a combination direct pumping and gravity system b. Water is pumped from the treatment facilities to elevated storage tanks 4 - Water Supply

7 c. Gravity flow is supplied by elevated tanks for storage and pressure (1) When consumption is high, the tanks supply extra water and pressure (2) Elevated reservoirs can ensure the water supply when other parts of the system may be inoperable D. Processing or treatment facilities 1. Provide treatment to remove contaminants and add chlorine to kill bacteria 2. May add fluoride or oxygen 3. The fire department's concern with treatment facilities is that a maintenance problem, power loss, or fire may reduce the volume and pressure of available water supplies 4. A secondary potential problem for fire fighters is the large quantities of chlorine which can be stored at these facilities E. Distribution systems 1. The amount and pressure of water that a distribution system can deliver depends on: a. The capacity of its pipe network b. The capacity of elevation of its storage tanks 2. As water flows through piping, its movement causes friction which reduces pressure Water Supply - 5

8 a. Friction loss is also increased by encrustations inside water mains b. Friction loss reduces the volume and pressure available from fire hydrants c. Less pressure will be lost when fire hydrants are supplied from two or more directions (1) Dead-end hydrant: receives water from only one direction (2) When a hydrant receives water from two or more directions, it has a circulating feed or looped line 3. Grid system: a distributing system that has circulating feed from several mains a. Primary feeders: large pipes that convey large quantities of water for distribution to smaller mains b. Secondary feeders: intermediate-sized pipes within the loops of primary feeders that aid the concentration of flow c. Distributors: smaller mains serving hydrants and blocks of consumers d. Two or more primary feeders should run from the water source to high-risk and industrial areas 4. Recommended size of supply mains from the American Water Works Association a. Residential hydrant supply mains: 6-inches 6 - Water Supply

9 b. Business and industrial districts: 8-inches with cross-connecting mains every 600 feet c. 12-inch mains should be on principal streets and in long mains 5. Water main valves a. Valves should be within the grid system so small districts can be shut off without affecting the entire system (1) The water department must be able to open valves when increased flow is needed during an emergency (2) In the event of a main break, the valves may have to be closed to isolate areas b. Indicating valves: visually show if valve is open or closed (1) Post indicator valve: a hollow metal post housing the valve stem with a small window which shows if the valve is open or shut (2) Outside screw and yoke (OS&Y) valve (a) Has a yoke on the outside with a threaded stem (b) The stem is extended when the valve is open and invisible when the valve is closed Water Supply - 7

10 c. Non-indicating valves (1) Usually buried or in manholes (2) Usually requires a special wrench or water valve key to operate d. Gate valves (1) May be indicating or non-indicating (2) Usually the non-rising stem type (3) The control valve is operated by a handle or screw mechanism which rises or lowers a plate into or out of the waterway e. Butterfly valves (1) May be indicating or non-indicating (2) The control valve is operated by a handle mechanism which rotates a valve disk to open or shut the valve f. If valves are not fully opened, friction loss increases and available water decreases 6. Water mains a. Underground water mains may be constructed of: (1) Cast or ductile iron (2) Asbestos cement (3) Steel 8 - Water Supply

11 (4) Polyvinyl chloride plastic (PVC) (5) Concrete b. A water main must be the proper type for the soil conditions and pressures needed (1) Some soil types may corrode some materials (2) Extra protection may be needed to prevent breaks in certain soil types c. The interior surface of the pipe creates resistance (friction loss) to water flow d. Encrustations and sediments in a pipe cause increased friction loss F. Pressures within water supply system 1. Pressure is the velocity of water through pipe or hose of a certain size 2. Static pressure a. Stored potential energy available to force water through pipes or hose b. Normal pressure within a system before a hydrant is opened c. True static pressure is rarely found in a water system 3. Normal operating pressure: pressure on a water system during normal use demands Water Supply - 9

12 4. Residual pressure: pressure left in a water system at a location when water is flowing 5. Flow pressure: forward pressure at a discharge opening III. Fire Hydrants (Essentials p. 605) A. Hydrant construction 1. Barrels, bonnets, and foot pieces are constructed from cast iron 2. Internal working parts are usually made of bronze 3. Valve facings may be rubber, leather, or composite materials B. Hydrant operations 1. As a safety precaution, tighten hydrant outlet caps that will not be used 2. Turn the outlet cap nut counterclockwise and remove the outlet cap 3. If time permits, flush the hydrant before connecting hoses 4. Turn operating nut in direction of arrow (usually counterclockwise) 5. Open and close hydrant slowly and fully a. Opening too fast may cause the hose attached to flail violently or burst 10 - Water Supply

13 b. Closing too fast can cause a sudden increase in water pressure within the water system (water hammer) C. Dry-barrel hydrants 1. Used in areas where freezing occurs 2. The valve holding back the water is located underground, below the anticipated frost line for the area 3. Water in the barrel of dry-barrel hydrant drains through a small drain hole at the bottom of the hydrant after closing 4. If the hydrant is not completely opened or closed, the drain hole will be partially open and cause soil erosion around the hydrant base 5. To test the ability for a hydrant to drain: a. After flowing water, close the hydrant and cap all discharges except one b. Place a hand over the open discharge c. A slight vacuum should be felt on the hand as the barrel drains 6. If water is bubbling up out of the ground at a dryhydrant's base when the hydrant is fully open, a broken component in the hydrant barrel is allowing water to get past the drain opening D. Wet-barrel hydrants 1. Used in areas with warmer climates where freezing is unlikely Water Supply - 11

14 2. Always filled with water to a compression valve at each outlet 3. Also referred to a "frost-free" or "California" hydrants E. Hydrant color coding from NFPA 291, Recommended Practice for Testing and Marking Hydrants 1. Light blue: 1,500 gpm or more 2. Green: 1,000 to 1499 gpm 3. Orange: 500 to 999 gpm 4. Red: less than 500 gpm 5. Local color-coding of hydrants differ depending on the jurisdiction F. Hydrant locations 1. Different jurisdictions have different requirements for hydrant spacing and locations depending on: a. Types of construction b. Types of occupancies c. Building densities d. Water main size e. Required fire flow for area occupancies 2. Generally, hydrants should not be spaced more than 300 feet apart in high-value districts 12 - Water Supply

15 G. Hydrant effectiveness may be affected by different factors 1. Obstructions erected too near a hydrant, such as signs, poles, fences, may limit access 2. Discharge outlets may face the wrong direction to allow hose attachment 3. Hydrant may have been damaged by traffic or vandalism 4. Corrosion may prevent the proper operation or impede the flow of water 5. Lack of clearance between outlet caps and the ground 6. Outlet caps missing or stuck in place with paint 7. Stem nut that cannot be turned or turns freely with no result 8. Obstructions (bottles, cans, rocks) inside hydrant outlets H. Testing hydrants 1. In some jurisdictions, hydrants are tested by a water department instead of the fire department a. Where fire departments do hydrant testing, fire fighters usually assist with the testing b. If the water system is privately-owned, the fire department should coordinate hydrant testing with the system owner Water Supply - 13

16 2. Pitot tube and gauge are used to test the flow pressure of a hydrant 3. Use of the pitot tube and gauge a. Pitot tube is held so that blade slices into water stream b. Open the petcock to make sure the air chamber is drained, close petcock c. Edge blade in stream with opening centered in stream d. Hold blade at a distance equal to about half the diameter of the orifice e. Tube should be parallel to the opening with the air chamber slightly above the center of the stream f. If the gauge is fluctuating, take the value between the highest and lowest readings 4. Fixed-mount pitot tubes are available to reduce the possibility of human error IV. Alternative Water Supplies (Essentials p. 610) A. Alternative water supplies may have to be used even in areas with adequate water systems 1. The water system may fail due to broken mains or power outages 2. Fires may occur in areas some distance from hydrants, such as fields or along limited-access highways 14 - Water Supply

17 3. Departments may have to draw water from sources such as lakes, ponds, rivers, swimming pools, and water tenders B. Drafting from a static source 1. Drawing water from a static source to supply a pumper is known as "drafting" 2. Hard suction intake hose is used primarily to draft water because it is designed to withstand the partial vacuum created when drafting without collapsing 3. Drafting operations are affected by debris, sediment, and rocks which can clog strainers, damage pumps, and clog nozzles a. Hard suction hoses must have strainers in place when drafting from a natural source b. Strainers can be supported by a ladder or floating strainer used to prevent hose from drawing in sediment c. A strainer should have at least 24-inches of water above and below it d. Floating strainers can draft from water as shallow as 24-inches deep 4. In some areas dry hydrants are installed at static water sources to supply water for fire fighting a. Usually constructed of steel or PVC pipe with strainers at the water source and large connections to connect to a pumper Water Supply - 15

18 b. In order to establish a water supply from a dry hydrant, hard suction must be used and a drafting operations set up 5. Drafting operations a. Suitable water source must be located for adequate water supply and to allow positioning of pumper nearby b. Pumper is positioned near water source c. Check hard suction coupling for dirt, debris, and worn gaskets d. The hard suction hose is attached to intake on pumper e. Strainer or floating strainer is attached to hard suction f. All connections must be air tight to allow for adequate draft g. If a floating strainer is not used, a ladder should be positioned in the water for the strainer to rest on h. Strainer is placed in water i. Pumper pulls a draft by priming the pump until positive pressure is indicated j. If unable to achieve draft, tighten connections with rubber mallet k. If still unable to get draft, lift may be too great for pumper to overcome 16 - Water Supply

19 C. Rural operations usually consist of water shuttle operations 1. Water is hauled from a supply by water tenders (tankers) to portable tanks where it can be drawn to the attack pumper 2. Water shuttles are recommended for distances greater than one-half mile or greater than the amount of supply line carried 3. Enough water tenders must be available to maintain the needed fire flow 4. To be successful, fast-fill and fast-dump times are required a. Water supply officers should be at both the fill site and dump site b. Personnel should be assigned to traffic control, fill site connections, and dumping c. If possible, tanker drivers should stay in their vehicles during the operations 5. Water shuttle operation components a. Water source - fill site b. Transport system: tankers/tenders c. Dump site - pumper drafting from tanks to either supply attack lines or supply another pumper used for fire attack d. Portable tanks (1) Range from 1,000 gallons and up Water Supply - 17

20 (2) May be collapsible or folding with a metal frame holding a synthetic or canvas duck liner (3) May be a self-supporting synthetic tank with a floating collar that rises as the tank is filled (4) Before opening a portable tank, a heavy tarp should be spread on the ground to protect the tank liner from damage (5) If possible, portable tanks should be positioned: (a) As level as possible to allow for maximum capacity (b) To allow for easy access for tankers from multiple directions (c) So as not to obstruct scene access for other apparatus (d) With the drain towards the lower side (6) Low-level strainers may be used to get the most water from the portable tanks (7) If multiple tanks are used, a jet-siphon can be used to transfer water between tanks (a) The jet-siphon may be incorporated into a low-level strainer and attached to hard suction hose, which is placed between the tanks (b) The jet-siphon draws the water through the hard suction hose 18 - Water Supply

21 e. Water tenders/tankers (1) NFPA 1901, Standard for Automotive Fire Apparatus, requires that water tenders on ground level be capable of dumping or filling rates of at least 1,000 gpm (2) Pumping water from a tanker should only by done by trained and qualified apparatus operators (3) Water tender unloading methods: (a) Gravity dumping through large (10- to 12-inch) dump valves (b) Jet dumps that increase the flow rate (c) Apparatus-mounted pumps that off-load the water (d) Combinations of these methods (4) Water tankers must be capable of being quickly refilled during emergency operations by using: (a) The best fill site or hydrant available (b) Large hoselines (c) Multiple hoselines (d) If necessary, a pumper with adequate flow Water Supply - 19

22 D. Relay pumping operations 1. Multiple pumpers can be used in a series to relay water to the scene if the water source is close enough 2. The water supply must be capable of maintaining the required volume for the incident's duration 3. The number of pumpers needed will depend on: a. The volume of water needed b. The distance from the water source to the scene c. The amount of hose available d. Pumper capacities 4. The pumper with the largest pumping capacity should be located at the water source 5. A relay pumping operation must be established quickly to be worthwhile V. Water Supply Summary A. For as long as there have been fire fighters, water has been the primary tool used to control fires B. Fire fighters must understand how water systems function to provide them with the water needed in an emergency C. More importantly, fire personnel must be proficient at getting the water from the supply source to the fire apparatus and then on the fire 20 - Water Supply

23 WATER SUPPLY QUIZ Name: Date: 1. The large pipes that convey large quantities of water for distribution to smaller mains are called. a. distributors b. secondary feeders c. primary feeders d. branch feeders 2. The pressure that is normally within a water supply system before water is flowing from the system is the. a. static pressure b. normal operating pressure c. residual pressure d. flow pressure 3. The pressure left in a water supply system when water is flowing is the. a. static pressure b. normal operating pressure c. residual pressure d. flow pressure 4. A hydrant is used in areas subject to freezing a. class A b. class B c. wet-barrel d. dry-barrel 5. Which of the following will not have an effect on hydrant effectiveness? a. Obstructions too near hydrant b. Whether it is a wet or dry hydrant c. Corrosion d. Failure to open fully Water Supply - 21

24 WATER SUPPLY QUIZ 6. Which of the following is not considered to be a part of a drafting operation? a. Static water source b. A pumper capable of drafting c. Fire hose d. Hard suction hose 7. The forward pressure at a discharge opening in a water supply system is the. a. static pressure b. normal operating pressure c. residual pressure d. flow pressure 8. Water bubbling up out of the ground at a dry hydrant's base when the hydrant is fully open is an indication that. a. the hydrant is properly draining b. excessive pressure within the hydrant is being relieved c. a broken component in the hydrant barrel is allowing water to get past the drain opening d. the drain opening at the base of the hydrant has ruptured 9. Drawing water from a static source to supply a pumper is known as. a. drafting b. a water shuttle c. gravity dumping d. jet-siphoning 10. When a hydrant connection is made, the hydrant should be opened. a. until water begins to flow b. to ½ of its maximum c. to ¾ of its maximum d. to a fully open position 22 - Water Supply

25 VENTILATION INSTRUCTOR'S GUIDE PRACTICAL SKILLS These Lead Instructor Practical Skills are designed to provide the Lead Instructor for a Fire Fighter I and II course with a more detailed overview of the practical skills required of all students. The appropriate skills from NFPA are listed at the front of each skill's section. Although the skills from NFPA are written as Job Performance Requirements, these have been divided into individual skill elements. This is to allow for consistency in the evaluation of each skill element. Students must successfully complete each step of each practical skill during the practical skills evaluation portion of a Fire Fighter I and II course. At the time of a Fire Fighter I and II Certification Examination, the skill steps have been prioritized to allow a student to miss a predetermined number of steps Water Supply

26 MISSOURI DIVISION OF FIRE SAFETY FIRE FIGHTER I & II PRACTICAL SKILLS Water Supply Successful completion of the practical skills in this section are necessary to fulfill the requirements of the following sections of NFPA : Fire Fighter I Standard * Connect a fire department pumper to a water supply as a member of a team, given supply or intake hose, hose tools, and a fire hydrant or static water source, so that connections are tight and water flow is unobstructed. Water Supply - 25

27 MISSOURI DIVISION OF FIRE SAFETY FIRE FIGHTER I & II PRACTICAL SKILLS Water Supply - NFPA , Demonstrate Operating a Hydrant Skill Objective: The candidate, given an equipped fire apparatus and hydrant, wearing protective equipment (SCBA optional), shall demonstrate making a hydrant connection from the hydrant to the pump intake using a 2 1 / 2 " soft supply hose and then fully open and close the hydrant. Skill Procedure: The evaluator should arrange for a fire apparatus to be positioned near a fire hydrant and identify which supply hose the candidate shall use to achieve the objective. The candidate shall then make the hydrant connection and fully turn the hydrant on. Students are allowed two chances at each skill for successful completion. Any step listed in italics missed shall result in failure of the skill. Otherwise, students are allowed to miss a maximum of two of the following steps and pass this skill. Items to be checked If the candidate: 1. As a safety precaution, tightens hydrant outlet caps that will not be used 2. Loosens appropriate hydrant cap and places the wrench on the operating nut 3. Connects hose completely to the hydrant 4. Threads other hose coupling to pump intake 5. Removes all kinks from the hose 6. Fully opens the hydrant 7. Closes hydrant fully and returns equipment 8. Checks for hydrant draining 26 - Water Supply

28 MISSOURI DIVISION OF FIRE SAFETY FIRE FIGHTER I & II PRACTICAL SKILLS Water Supply - NFPA , Demonstrate Assembling the Equipment for Drafting Skill Objective: Given the necessary equipment, the fire fighter shall assemble and connect the equipment necessary for drafting from a static water supply source. Skill Procedure: The candidate should be given all of the necessary equipment to perform this task. This skill should be conducted in an open area free of traffic and pedestrians. It is not necessary to actually draft water as part of the skill. If possible, the candidate should use the pump intake the same size as the hard sleeve to reduce the need for adapters. Students are allowed two chances at each skill for successful completion. Students are allowed to miss a maximum of one of the following steps and pass this skill. Items to be checked If the candidate: 1. Checks gaskets on hard suction hose for dirt or gravel 2. Connects the sections of hard suction hose 3. Connects the strainer to one end of the hard suction hose 4. Removes pump intake cap on pumper 5. Connects hard suction hose to pumper intake 6. Hand tightens hard suction coupling to pump intake 7. Dismantles drafting equipment and returns to proper storage on apparatus Water Supply - 27