The minimum acceptable criteria for the installation of reduced pressure backflow prevention devices, double check valve assemblies or other backflow prevention devices requiring regular inspection or testing shall include the following.
(A) All required devices shall be installed in accordance with the provisions of this chapter, by a person approved by the water system who is knowledgeable in the proper installation. Only licensed sprinkler contractors may install, repair or test backflow prevention devices on fire protection systems.
(B) An approved backflow prevention assembly shall be installed on each service line to a customer's premises and in all cases, before the first branch line leading off the service line, if it is impractical or easily altered to provide an effective air gap separation, when any of the following conditions exist.
(C) All devices shall be installed in accordance with the manufacturer's instructions and shall possess appropriate test cocks, fittings and caps required for the testing of the device (except hose bibb vacuum breakers). All fittings shall be of brass construction, unless otherwise approved by the water system, and shall permit direct connection to department test equipment.
(D) The entire device, including valves and test cocks, shall be easily accessible for testing and repair.
(E) All devices shall be placed in the upright position in a horizontal run of pipe.
(F) Devices shall be protected from freezing, vandalism, mechanical abuse and from any corrosive, sticky, greasy, abrasive or other damaging environment.
(G) (1) Reduced pressure backflow prevention devices shall be located a minimum of 12 inches, plus the nominal diameter of the device above either:
(a) The floor;
(b) The top of opening(s) in the enclosure; or
(c) Maximum flood level, whichever is higher.
(2) Maximum height above the floor surface shall not exceed 60 inches.
(H) Clearance from wall surfaces or other obstructions shall be at least six inches. Devices located in non-removal enclosures shall have at least 24 inches of clearance on each side of the device for testing and repairs.
(I) Devices shall be positioned where a discharge from the relief port will not create undesirable conditions. The relief port must never be plugged, restricted or solidly piped to a drain.
(J) An approved air-gap shall separate the relief port from any drainage system. An approved air-gap shall be at least twice the inside diameter of the supply line, but never less than one inch.
(K) An approved strainer shall be installed immediately upstream of the backflow prevention device, except in the case of a fire protection system.
(L) Devices shall be located in an area free from submergence or flood potential, therefore never in a below grade pit or vault. All devices shall be adequately supported to prevent sagging.
(M) Adequate drainage shall be provided for all devices. Reduced pressure backflow prevention devices shall be drained to the outside whenever possible.
(N) Fire hydrant drains shall not be connected to the sewer, nor shall fire hydrants be installed the that backflow/back-siphonage through the drain may occur.
(O) Enclosures for outside installations shall meet the following criteria.
(1) All enclosures for backflow prevention devices shall be as manufactured by a AWWA approved company or an approved equal.
(2) For backflow prevention devices up to and including two inches, the enclosure shall be constructed of adequate material to protect the device from vandalism and freezing, and shall be approved by the water system. The complete assembly, including valve stems and handwheels, shall be protected by being inside the enclosure.
(3) To provide access for backflow prevention devices up to and including two inches, the enclosures shall be completely removable. Access for backflow prevention devices two and one-half inches and larger shall be provided through a minimum of two access panels. The access panels shall be of the same height as the enclosure and shall be completely removable. All access panels shall be provided with built-in locks.
(4) The enclosure shall be mounted to a concrete pad as specified by the manufacturer, but in no case less than four inches thick. The enclosure shall be constructed, assembled and/or mounted in the a manner that it will remain locked and secured to the pad even if any outside fasteners are removed. All hardware and fasteners shall be constructed of 300 series stainless steel.
(5) Heating equipment, if required, shall be designed and furnished by the manufacturer of the enclosure to maintain and interior temperature of +40°F with an outside temperature of -30°F and a wind velocity of 115 mph.
(P) Where the use of water is critical to the continuance of normal operations or the protection of life, property or equipment, duplicate backflow prevention devices shall be provided to avoid the necessity of discontinuing water service to test or repair the protective device. Where it is found that only one device has been installed and the continuance of service is critical, the water system shall notify, in writing, the occupant of the premises of plans to interrupt water services and arrange for a mutually acceptable time to test the device. In the cases, the utility may require the installation of a duplicate device.
(Q) The utility shall require the occupant of the premises to keep any backflow prevention devices working properly, and to make all indicated repairs promptly. Repairs shall be made by qualified personnel acceptable to the water system. Expense of the repairs shall be borne by the owner or occupant of the premises. The failure to maintain a backflow prevention device in proper working condition shall be grounds for discontinuance of water service to premises. Likewise the removal, bypassing or alteration of a backflow prevention device or the installation thereof, so as to render a device ineffective shall constitute a violation of this chapter and shall be grounds for discontinuance of water service. Water service to the premises shall not be restored until the customer has corrected or eliminated the conditions or defects to the satisfaction of the water system.
(Ord. 1297, passed 4-12-2011)