15 Water Supply

15 Objectives (1 of 2) Discuss rural water supplies. Describe how portable tanks are used to supply water for firefighting. Describe the sources of water for a municipal water supply system.

15 Objectives (2 of 2) Describe the major features of a municipal water distribution system. Describe dry-barrel fire hydrants and wet- barrel fire hydrants. Discuss maintaining a fire hydrant. Define static pressure, residual pressure, and flow pressure.

15 Introduction (1 of 2) An uninterrupted water supply is: –The primary weapon for extinguishment –Essential for fire fighter safety Ensuring a dependable water supply is a critical fire-ground operation and must be accomplished as soon as possible.

15 Introduction (2 of 2) Water sources include: –Municipal and private water systems –Static water sources

15 Rural Water Supplies Residents of rural areas usually depend on wells or cisterns to provide water. No hydrants in these areas, so water must be obtained from other sources

15 Static Water Sources (1 of 3) Static sources include: –Rivers or streams –Lakes, ponds, oceans –Canals or reservoirs –Swimming pools –Cisterns

15 Static Water Sources (2 of 3) Must be accessible to a fire engine or portable pump –Is there a road or hard surface within 20‘ of the source? May have a dry hydrant permanently installed for speed and reliability

15 Static Water Sources (3 of 3)

15 Mobile Water Supply Apparatus Tankers or water tenders Designed to carry large volumes of water to the fire Generally carry 1000– 3500 gallons May be used to pump water directly into attack engine

15 Portable Tanks (1 of 2) Carried on fire apparatus to be quickly set up at the fire scene Typically hold 600– 5000 gallons of water Tankers are used to fill the portable tanks.

15 Portable Tanks (2 of 2) The pump operator drafts from the tanks. Dump valves on the tankers allow them to off-load up to 3000 gallons per minute.

15 Tanker Shuttles Used to deliver a large volume of water over a long period of time Number required depends on –Distance between fill site and fire scene –Time it takes to dump and to refill –Flow rate required at the fire scene Fill site should be designed to refill tankers without delays

15 Municipal Water Systems Provide clean water for public use. Provide water for fire protection. Most are owned and operated by a local government agency. Systems includes water sources, water treatment facilities, and a water distribution system.

15 Water Sources Sources include: –Wells –Rivers or streams –Lakes –Reservoirs Many systems draw water from several sources.

15 Water Distribution Systems (1 of 5) Water mains deliver water from treatment facilities to the end user. Include pumps, storage tanks, and reservoirs

15 Water Distribution Systems (2 of 5) Water pressure –Generally 20–80 psi –Hydrant pressure should not drop below 20 psi. –Usually produced by pumps (directly or indirectly)

15 Water Distribution Systems (3 of 5) Water pressure may also be produced by gravity. –Gravity-feed system –Elevated water storage towers

15 Water Distribution Systems (4 of 5) Water mains typically follow a grid system. May have dead-end mains –Water enters from only one direction. –Limited available water supply

15 Water Distribution Systems (5 of 5) Water main valves –Control valves: Located throughout system to shut down sections –Shut-off valves: Used to shut off water flow to individual customers or to hydrants

15 Fire Hydrants Provide water for firefighting purposes Installed on both public and private water systems Consist of an upright steel casing attached to the underground distribution system

15 Dry-Barrel Hydrants Used in cold climates Hydrant valve is located at the base of the barrel. Water flows into the hydrant only when it is needed.

15 Fire Hydrants Locations Located according to local standards and nationally recommended practices –Every 900' in residential areas; every 300' in high-value areas in Medina County. –Every intersection; mid-block when over set distances –Based on occupancy, construction, and size of the buildings

15 Fire Hydrant Operation Turning on a hydrant. Individual fire departments may have their own variations on this procedure. –Removed needed caps –Connect Hydrant Valve to 2 ½” discharge –Flush hydrant –Connect hose –Open hydrant completely

15 Inspecting Fire Hydrants (1 of 3) Check for visibility and access. Check for exterior damage. Ensure barrel is dry and free of debris. Ensure all caps in good working order. Open valve for water flow until clear. Shut down and ensure proper draining. Replace cap.

15 Inspecting Fire Hydrants (2 of 3)

15 Inspecting Fire Hydrants (3 of 3) To clean threads, use a steel brush. Replace cracked, broke, or missing cap gaskets. Lubricate as recommended by manufacturer.

15 Flow and Pressure (2 of 3) Static pressure: Pressure when no water is moving –Measured by placing a gauge on a port with no water in the system moving

15 Flow and Pressure (3 of 3) Residual pressure: Amount of pressure that remains in the system when water is flowing

15 Summary Rural water supply utilizes fill sites, tankers, and portable tanks. Municipal system has three components. Hydrants may be wet-barrel or dry-barrel. Inspection of hydrants is needed annually. Testing is done to determine maximum flow availability.