Water Supply

Water SupplyIntermediate SFFMA Objectives:12-02.01 12-02.064Hrs receivedSFFMA Objectives12-02.01 Trainee shall identify the following types of water main valves: A. indicating C. post indicators B. non-indicating D. outside screw and yoke 12-02.02 Trainee shall identify hydrant usability by: A. obstruction to use of hydrantB. direction of hydrant outlets to suitability of use operating the hydrant C. mechanical aboveground damageD. condition of paint for rust and corrosionE. the flow by fullyF. the ability to drain12-02.03 Trainee shall define, explain, and demonstrate where applicable, the use of a rural dry fire hydrant system and static water supply source. 12-02.04 Trainee shall define a tanker shuttle.12-02.05 Trainee shall identify the apparatus, equipment, and appliances required to provide water at rural locations by relay pumping, large diameter hose, or a tanker shuttle. 12-02.06 Trainee shall demonstrate deployment of a portable water tank. Water Main ValvesProvide means for controlling flow of water through distribution pipingShould be located at frequent intervals in grid system so only small sections are cut off if necessary to isolate parts of system for repairsFirefighter II123(Continued)Water Main ValvesFirefighter II124

(Continued)Water Main ValvesSpacing should be such that only minimum length of pipe is out of service at any timeShould be operated at least once/year to keep workingWater department should be able to open valves promptly when neededFirefighter II125(Continued)Water Main ValvesIndicating valvesShow position of gate or valve seatIncludes most valves in fire protection systemsPost indicator valves (PIVs)Outside stem and yoke (OS&Y) valvesFirefighter II126(Continued)

Water Main ValvesOS&Y Valve (Outside stem and yoke)A type of control valve for a sprinkler system in which the position of the center screw indicates whether the valve is open or closedPost Indicating ValveValve type used to control underground water mains that provides visual means for indicating open or shutWater Main ValvesNonindicating valvesNormally buried/installed in utility manholesCan be operated aboveground through valve box or may need special socket wrench on end of reach rodFirefighter II128(Continued)

Water Main ValvesControl valvesCan be indicating or nonindicating typesGate valvesButterfly valvesFirefighter II129(Continued)

Water Main ValvesProper valve installation (spacing)Necessary to close off one or two hydrants from service while single break in main is being repairedAdvantages reduced if all valves not properly maintained and kept openFirefighter II1210Water MainsGenerally made of cast iron, ductile iron, asbestos cement, steel, PVC, plastic, or concreteMust be proper type for soil conditions, and pressures to which will be subjected

Firefighter II1211(Continued)Water MainsWater flow may be resisted by internal surface of pipe, encrustations, solidified sedimentsFirefighter II1212

PressureForce per unit areaForce that moves water through conduitMeasured in pounds per square inch (psi) or kilopascals (kPa)Firefighter II1213Static PressureWhen little or no water flow, pressure that can be measured is static pressureRarely found in public water supply systemFirefighter II1214

(Continued)Static PressureDefined in this context as normal pressure existing on system before water released from hydrant

Firefighter II1215Flow PressureForward velocity pressure at discharge opening while water flowingCan be measured with pitot tube and gaugeFirefighter II1216

Residual PressureRepresents pressure left in system at specific location when water flowingFirefighter II1217

(Continued)Residual PressureThat part of total available pressure not used to overcome friction/gravity while forcing waterProvides indication of availability of additional water

Firefighter II1218Dry HydrantsInstalled at static water sources to increase water supply availableUsually constructed of steel or PVC pipe with strainers at water source, steamer ports to connect to pumperDesigned to supply at least 1,000 gpm (4 000 L/min)Firefighter I1219(Continued)Water ShuttlesInvolve hauling water from supply source to portable tanks from which water may be drawn to fight fireRecommended for distances greater than mile (0.8 km) or greater than the fire departments capability of laying supply hoselinesFirefighter I1220(Continued)Water ShuttlesCritical elementsFast-fill, fast-dump capabilitiesWater supply officers at fill/dump sitesTraffic controlHydrant operationsHookupsTank ventingFirefighter I1221

Water ShuttlesKey componentsDump sitePortable tanksFirefighter I1222(Continued)

Water ShuttlesWays in which water tenders unloadGravity dumpingJet dumps that increase flow rateApparatus-mounted pumpsCombination of these methodsFirefighter I1223(Continued)

Water ShuttlesAccording to NFPA 1901, water tenders on level ground should be capable of dumping/filling at rates of at least 1,000 gpm (4 000 L/min)Firefighter I1224(Continued)Water ShuttlesTo fill water tenders quickly, use best fill site, large hoselines, multiple hoselinesMultiple portable pumps may be necessaryFirefighter I1225DISCUSSION QUESTIONWhat are the advantages and disadvantages of a water shuttle operation?Firefighter I1226

Relay PumpingCan be used in situations where water source is close enough to fire scene to render water shuttles unnecessaryFactors to considerWater supply must be capable of maintaining desired volume of waterRelay must be established quicklyFirefighter I1227(Continued)Relay PumpingDetermining number of pumpers needed and distance between themSeveral factors to take into accountApparatus with greatest pumping capacity should be at water sourceFirefighter I1228(Continued)Relay PumpingDetermining number of pumpers needed and distance between them Large-diameter hose or multiple hoselines increase distance, volume a relay can supplyWater supply officer should consider all factors and determine correct distanceFirefighter I1229Practical ExerciseFirefighter shall:Identify apparatus, equipment, and appliances required to provide water at rural locations byRelay pumping orLarge diameter hose orTanker shuttleFirefighter shall:Demonstrate deployment of a portable water tank