A. Assemblies shall be installed at the service connection or near the property line but in all cases, before the first branch line leading off of the service line, and in an accessible location approved by the department. All assemblies shall be shown and specified on all required building and engineering plans and approval shall be obtained prior to issuance of building and/or engineering permit. All assemblies shall be installed according to standard detail.
B. Backflow preventive assemblies shall have at least the same cross sectional area as the water service and/or meter. In those instances where a continuous water supply is necessary, or if the water supply cannot be temporarily interrupted for testing of assemblies, then two (2) sets of backflow preventive assemblies shall be installed in parallel.
C. No bypass shall be installed around backflow prevention assemblies.
D. Double check valve assemblies may be installed belowground in a vault if approved, in writing, on a case by case basis, by the department. Double check valve assemblies installed in vaults shall have sufficient clearance provided to permit testing in place or removal for maintenance, as prescribed in the standard details. Copies are available upon request from the department.
E. A reduced pressure principle backflow preventive assembly shall be installed aboveground. Assemblies installed shall be accessible for testing as not to endanger the tester. Under no conditions except as provided for herein will backflow prevention assemblies be installed less than twelve inches (12") or more than twenty four inches (24") above grade level.
F. All pressure type backflow prevention assemblies which are designed for periodic field testing shall be equipped with resilient seated valves on both the upstream and the downstream side of the assembly. In addition, test cocks shall be provided and located so that test equipment may be connected to the assembly at such points that the pressure in each pressure zone may be detected and, in addition, a test cock shall be located upstream of the upstream shutoff valve, as close as possible to the upstream shutoff valve.
G. Backflow assemblies shall be protected from freezing by a method acceptable to the department. (Ord. O 12-01, 2-7-2012)