W. Va. Code R. § 64-77-10

Current through Register Vol. XLI, No. 45, November 8, 2024

Section 64-77-10 - Distribution Systems

10.1. Materials.

10.1.a. Standards and materials selection. -- Pipe, fittings, valves and fire hydrants shall conform to ASTM, AWWA standards, meet ANSI/NSF Standard 61: Drinking Water System Components - Health Effects and shall be acceptable to the BPH. In the absence of these standards, materials meeting applicable product standards and acceptable to the BPH may be selected. Special attention shall be given to selecting pipe materials that protect against both internal and external pipe corrosion. Pipes and pipe fittings containing more than eight percent (8%) lead shall not be used. All products shall comply with ANSI/NSF Standard 61: Drinking Water System Components - Health Effects.

10.1.b. Permeation of system by organic compounds. -- Where distribution systems are installed in areas of groundwater contaminated by organic compounds: pipe and joint materials that are not subject to permeation of the organic compounds shall be used; and non-permeable materials shall be used for all portions of the system including water main, service connections and hydrant leads.

10.1.c. Used materials. -- Water mains that have been used previously for conveying potable water may be reused provided they meet the standards contained in this rule.

10.1.d. Joints. -- Packing and jointing materials used in the joints of pipe shall meet the standards of the AWWA, ANSI/NSF Standard 61 and the BPH. Pipe having mechanical joints or slip-on joints with rubber gaskets is preferred. Lead-tip gaskets shall not be used. Repairs to lead-joint pipe shall be made using alternative methods. Manufacturer approved transition joints shall be used between dissimilar piping materials.

10.2. Water Main Design.

10.2.a. All distribution systems shall be designed to provide a residential peak demand flow (not including fire flows) in accordance with Table 64-77E of this rule.

10.2.b. Pressure. -- All water mains, including those not designed to provide fire protection, shall be sized after a hydraulic analysis based on peak flow demands and pressure requirements. The system shall be designed to maintain a minimum pressure of twenty (20) pounds per square inch at ground level at all points in the distribution system under all conditions of flow and thirty (30) pounds per square inch under static conditions. The normal working pressure in the distribution system shall be designed based upon the pipe manufacturer's recommendations and the applicable AWWA standards for the type of pipe.

10.2.c. Surge Pressures. -- All water mains shall be designed to provide adequate strength to withstand water surge pressure. Table 64-77F of this rule lists the minimum acceptable pressure surge for PVC for each foot per second velocity of water. Design shall allow for at least five (5) feet per second instantaneous flow velocity change or higher if conditions warrant.

10.2.d. Diameter. -- The minimum size of a water main for providing fire protection and serving fire hydrants shall be of six (6) inch diameter. Larger size mains are required if necessary to allow the withdrawal of the required fire flow while maintaining the minimum residual pressures.

10.2.e. Fire protection. -- When fire protection is to be provided, the recommended system design shall be such that fire flows and facilities are in accordance with the requirements of the ISO. Under no circumstances shall fire flows be less than two hundred fifty (250) gallons per minute.

10.2.f. Small mains. -- Any departure from minimum six (6) inch diameter requirements shall be justified by hydraulic analysis and future water use, and can be considered only in special circumstances; however, no mains less than two (2) inches are permitted.

10.2.g. Hydrants. -- Water mains not designed to carry fire-flows shall not have fire hydrants connected to them.

10.2.h. Dead ends. -- In order to provide increased reliability of service and reduce head loss, dead ends shall be minimized by making appropriate tie-ins whenever practical. Where dead-end mains occur, they shall be provided with a fire hydrant if flow and pressure are sufficient, or with a flushing hydrant or blow-off, approved by the BPH, for flushing purposes. Flushing devices shall be sized to provide flows that give a velocity of at least two and a half (2.5) feet per second in the water main being flushed. No flushing devices shall be directly connected to any sewer.

10.3. Valves. -- A sufficient number of valves shall be provided on water mains so that inconvenience and sanitary hazards are minimized during repairs. Valves shall be located at not more than five hundred (500) foot intervals in commercial districts and at not more than one block or eight hundred (800) foot intervals in other districts. Where systems serve widely scattered customers and where future development is not expected, the valve spacing shall not exceed two thousand five hundred (2,500) feet.

10.4. Hydrants.

10.4.a. Location and spacing. -- Hydrants shall be provided at each street intersection and at intermediate points between intersections as recommended by the ISO. Generally, hydrant spacing may range from three hundred fifty (350) to one thousand (1000) feet depending on the area being served.

10.4.b. Valves and nozzles. -- Fire hydrants shall have a bottom valve size of at least five (5") inches, one four and one half (41/2") inch pumper nozzle and two (2) two and a half (21/2") inch nozzles.

10.4.c. Hydrant leads. -- The hydrant lead shall be a minimum of six (6) inches in diameter. Auxiliary valves shall be installed in all hydrant leads.

10.4.d. Drainage. -- Hydrant drains shall be provided with a gravel pocket, or a dry well shall be provided unless the natural soils provide adequate drainage. Hydrant drains shall not be connected to or located within ten (10) feet of sanitary sewers or storm drains.

10.4.e. Draining type frost proof yard hydrants are not permitted.

10.5. Air Relief Valves, Valve, Meter and Blow-off Chambers.

10.5.a. Air relief valves. -- At high points in water mains where air can accumulate, provisions shall be made to remove the air by means of hydrants or air relief valves. Automatic air relief valves shall not be used in situations where flooding of the manhole or chamber may occur.

10.5.b. Air relief valve piping. -- The open end of an air relief pipe from automatic valves shall be provided with a screened, downward-facing elbow. The pipe from a manually operated valve shall be extended to the top of the pit. Use of manual air relief valves is recommended wherever possible.

10.5.c. Chamber drainage. -- Chambers, pits or manholes containing valves, blow-offs, meters or other such appurtenances to a distribution system shall not be connected directly to any storm drain or sanitary sewer nor shall blow-offs or air relief valves be connected directly to any sewer. These chambers or pits shall be drained to the surface of the ground where they are not subject to flooding by surface water or to absorption pits underground.

10.6. Installation of Mains.

10.6.a. Standards. -- Specifications shall incorporate the provisions of the AWWA standards and manufacturer's recommended installation procedures.

10.6.b. Bedding. -- A continuous and uniform bedding shall be provided in the trench for all buried pipe. Backfill material shall be tamped in layers around the pipe and to a sufficient height above the pipe to adequately support and protect the pipe. Stones found in the trench shall be removed for a depth of at least six (6) inches below the bottom of the pipe.

10.6.c. Cover. -- All water mains shall be covered with sufficient earth or other insulation to prevent freezing. All distribution mains shall be provided with a minimum of thirty-six (36) inches of earth covering; forty-two (42) inches are recommended. All mains of less than eight (8) inches in diameter within five (5) feet of a heavily traveled highway shall be provided with at least forty-two (42) inches of cover.

10.6.d. Blocking. -- All tees, bends, plugs and hydrants shall be provided with reaction blocking, tie rods or joints designed to prevent movement.

10.6.e. Pressure and leakage testing. -- All types of installed pipe shall be pressure tested and leakage tested in accordance with AWWA Standard C600.

10.6.f. Disinfection. -- All new, cleaned or repaired water mains shall be disinfected in accordance with AWWA Standard C651. The specifications shall include microbiological testing of all water mains. Microbiological sampling shall be collected by a BPH certified public water system operator or other individual authorized by the BPH.

10.6.g. All non-metallic mains shall be provided with tracer wire or metallic tape.

10.6.h. Anchoring of fusible pipe. -- Additional restraint may be necessary on fusible pipe at the connection to appurtenances or transitions to different pipe materials to prevent separation of joints. The restraint may be provided in the form of an anchor ring encased in concrete or other methods as approved by the BPH.

10.6.i. External corrosion. -- If soils are found to be aggressive, necessary action to protect the water main shall be taken, such as by encasement of the water main in polyethylene, provision of cathodic protection (in very severe instances), or using corrosion resistant water main materials.

10.7. Separation of Water Mains, Sanitary Sewers and Storm Sewers.

10.7.a. General. -- The following factors shall be considered in providing adequate separation: materials and type of joints for water and sewer pipes; soil conditions; service and branch connections into the water main and sewer line compensating variations in the horizontal and vertical separations; space for repair and alterations of water and sewer pipes and off-setting of pipes around manholes.

10.7.b. Parallel installation. -- Water mains shall be laid at least ten (10) feet horizontally from any existing or proposed sewer. The distance shall be measured edge to edge.

10.7.c. Crossings. -- Water mains shall cross above sewers and shall be laid to provide a minimum vertical distance of eighteen (18) inches between the bottom of the water main and the top of the sewer. At crossings, one full length (20 feet) of water pipe shall be located so both joints will be as far from the sewer as possible. Special structural support for the water and sewer pipes may be required.

10.7.d. Force mains. -- There shall be at least a ten (10) foot horizontal separation between water mains and sanitary sewer force mains. There shall be an eighteen (18) inch vertical separation at crossings as required.

10.7.e. Exception. -- The BPH may approve a variance from the above requirements when it determines that compliance with the specified separation distances cannot be practically achieved.

10.7.f. Sewer manholes. -- No water pipe shall pass through or come in contact with any part of a sewer manhole.

10.7.g. Separation of water mains from other sources of contamination. -- Design engineers shall exercise caution when locating water mains at or near certain sites such as sewage treatment plants or industrial complexes. Individual septic tanks shall be located and avoided. The engineer shall contact the BPH to establish specific design requirements for locating water mains near any source of contamination.

10.8. Surface Water Crossings. -- The BPH shall be consulted before final plans are prepared.

10.8.a. Above-water crossings. -- An above-water crossing pipe shall be adequately supported and anchored, be protected from vandalism, damage and freezing and be accessible for repair or replacement.

10.8.b. Underwater crossings. -- A minimum cover of three (3) feet shall be provided over the pipe unless otherwise approved by the BPH. When crossing water courses that are greater than fifteen (15) feet in width, the following shall be provided: the pipe shall be of special construction, having flexible watertight joints; valves shall be provided at both ends of water crossings so that the section can be isolated for testing or repair; the valves shall be easily accessible, and not subject to flooding; and permanent taps shall be made on each side of the valve to allow insertion of a small meter to determine leakage and for sampling purposes.

10.9. Cross-connections and Interconnections.

10.9.a. Cross-connections. -- There shall be no connection between the distribution system and any pipes, pumps, hydrants, or tanks whereby unsafe water or other contaminating materials may be discharged or drawn into the system. Each water utility shall have a program conforming to the BPH requirements to detect and eliminate cross connections.

10.9.b. Cooling water. -- Neither steam condensate nor cooling water from engine jackets or other heat exchange devices shall be returned to the potable water supply.

10.9.c. Interconnections. -- The approval of the BPH shall be obtained for interconnections between approved public water systems.

10.10. Water Services and Plumbing.

10.10.a. Plumbing. -- Water services and plumbing shall conform to relevant local and state plumbing codes or to the applicable National Plumbing Code. Solders and flux containing more than two tenths percent (0.2%) lead and pipe and pipe fittings containing more than eight percent (8%) lead shall not be used. The public water system is not responsible for an individual customer's private plumbing.

10.10.b. Booster pumps. -- Individual booster pumps are not allowed for any individual service from the public water supply mains where residual pressures are less than five (5) pounds per square inch under all flow conditions. Where used, backflow prevention, approved by the BPH, consisting of at least a double check valve assembly shall be provided by the customer to protect the public water supply.

10.11. Service Meters. -- Each service connection shall be individually metered.

10.12. Water Loading Stations. -- Water loading stations present special problems since the fill line may be used for filling both potable water vessels and other tanks or contaminated vessels. To prevent contamination of both the public supply and potable water vessels being filled, the following principles shall be met in the design of water loading stations: there shall be a double check valve assembly approved by the BPH and installed to prevent backflow to the public water supply; the piping arrangement shall prevent contaminant being transferred from a hauling vessel to another. Hoses shall not be contaminated by contact with the ground and shall be capped when not in use. Water meters shall be provided.

W. Va. Code R. § 64-77-10