(A) Backflow prevention assemblies shall be installed in accordance with the town and state regulations.
(B) Backflow prevention assembly installations shall be inspected and approved for use by the town.
(1) Additionally, most new installations such as sprinklers and irrigation will require a state plumbing permit and inspection.
(2) All backflow assemblies shall be installed in the horizontal position. Vertical installation shall be acceptable when approved by ASSE, ABPA or FCCC and HR specifications. Variance may be granted by review and town approval.
(3) A pressure vacuum breaker shall be used where the assembly is never subjected to back- pressure and installed a minimum of 12 inches above the highest piping or outlet downstream of the assembly in a manner to preclude back-pressure.
(C) An atmospheric vacuum breaker shall be used where the assembly is:
(1) Installed as an isolation assembly;
(2) Never subjected to continuous pressure (more than 12 consecutive hours);
(3) Installed with the air inlet in a level position and a minimum of six inches above the highest piping or outlet it is protecting;
(4) The single check valve is not considered a backflow prevention assembly;
(5) Double check valve assemblies may be installed in below ground vaults when these vaults are properly constructed in accordance with the town standards. They must be insulated to prevent freezing;
(6) (a) Reduced pressure backflow preventers will be installed above ground. The unit should be placed at least 12 inches above the finish grade to allow clearance for the repair work.
(b) A concrete slab at finish grade is recommended. Proper drainage should be provided for the relief valve and may be piped away from the location; provided, it is readily visible from above grade and provided the relief valve is separated from the drain line by a minimum of double the diameter of the supply line.
(c) A modified vault installation may be used if constructed with ample side clearances. Freezing is a major problem in this area;
(7) A hose bib vacuum breaker will be installed on each residential hose bib where a well exists on the property and the hose bib does not have anti-siphon protection itself, and must be approved for use by the town; and
(8) Connection to a fire hydrant requires either air-gap protection or a reduced pressure zone (RPZ) Valve to be used for bulk water tank filling.
(Prior Code, § 135.5.6) (Ord. 398, passed 6-6-1996; Ord. 577, passed 11-6-2014; Ord. 586, passed 12-3-2015)