A. Approved Backflow Prevention Assemblies:
1. Only backflow prevention assemblies which have been approved by the City shall be acceptable for installation by a water user connected to the City's potable water system.
2. The City will provide, upon request, to any affected user, a list of approved backflow prevention assemblies.
B. Backflow Prevention Assembly Installation:
1. Backflow prevention assemblies shall be installed in a manner prescribed in the Standards and Specifications for Public Works Construction adopted by the City. Location of the assemblies shall be as close as practical to the user's service connection. The City shall have the final authority in determining the required location of a backflow prevention assembly.
a. Air-Gap Separation (AG): The air-gap separation shall be located on the user's side of and as close to the service connection as practical. All piping from the service connection to the receiving tank shall be above grade and be entirely visible. No water use shall be provided from any point between the service connection and the air-gap separation. The water inlet piping shall terminate a distance of at least two (2) pipe diameters of the supply inlet, but in no case less than one inch (1") above the overflow rim of the receiving tank.
b. Reduced Pressure Principle Backflow Prevention Assembly (RP): The approved reduced pressure principle assembly shall be installed on the user's side of and as close to the service connection as is practical. The assembly shall be installed a minimum of twelve inches (12") above grade and not more than thirty six inches (36") above grade, measured from the bottom of the assembly and with a minimum of twelve inches (12") side clearance. The assembly shall be installed so that it is readily accessible for maintenance and testing. Water supplied from any point between the service connection and the RP assembly shall be protected in a manner approved by the City.
c. Double Check Valve Assembly (DC): The approved double check valve assembly shall be installed on the user's side of and as close to the service connection as is practical. The DC shall be installed above grade, if possible, and in a manner where it is readily accessible for testing and maintenance. If a double check valve assembly is put below grade, it must be installed in a vault such that there is a minimum of six inches (6") between the bottom of the vault and the bottom of the assembly, so that the top of the assembly is a maximum of eight inches (8") below grade, so there is a minimum of twenty four inches (24") of clearance between the side of the assembly with the test cocks and the side of the vault, and so there is a minimum of twelve inches (12") clearance between the other side of the assembly and the side of the vault. Special consideration must be given to double check valve assemblies of the "Y" type. These assemblies must be installed on their "side" with the test cocks in a vertical position so that either check valve may be removed for service without removing the assembly. Vaults that do not have an integrated bottom must be placed on a three inch (3") layer of gravel.
C. Backflow Prevention Assembly Testing And Maintenance:
1. Testing Requirements; Repair And Maintenance; Costs: The owner of any premises on which, or on account of which, backflow prevention assemblies are installed shall have the assemblies tested by a person who has demonstrated competency in testing of these assemblies to the City. Backflow prevention assemblies must be tested at least annually and immediately after installation, relocation or repair. The City may require a more frequent testing schedule if it is determined to be necessary. No assembly shall be placed back in service unless it is functioning as required. A report in a form acceptable to the City must be filed with the City each time an assembly is tested, relocated or repaired. These assemblies shall be serviced, overhauled, or replaced whenever they are found to be defective, and all costs of testing, repair and maintenance shall be borne by the water user.
2. List Provided; Notification Of Testing; Forms: The City will supply affected water users with a list of persons acceptable to the City to test backflow prevention assemblies. The City will notify affected customers by mail when periodic testing of an assembly is required and will also supply users with the necessary forms which must be filled out each time an assembly is tested or repaired.
3. City Testing; Charges: Upon request, the City will test a water user's backflow prevention assembly to fulfill the requirements of this Chapter. The water user will be charged on the next regular water bill for the test and any maintenance found necessary to keep the assembly in working order.
4. Backflow Prevention Assembly Removals: Approval must be obtained from the City before a backflow prevention assembly is removed, relocated, or replaced.
a. Removal: The use of an assembly may be discontinued and the assembly removed from service upon presentation of sufficient evidence to the City to verify that a hazard no longer exists or is not likely to be created in the future.
b. Relocation: An assembly may be relocated following confirmation by the City that the relocation will continue to provide the required protection and satisfy installation requirements. A retest will be required following the relocation of the assembly.
c. Repair: An assembly may be removed for repair, provided the water use is either discontinued until the repair is completed and the assembly is tested and returned to service, or the service connection is equipped with other backflow protection approved by the City. The retest will be required following the repair of the assembly.
d. Replacement: An assembly may be removed and replaced provided the water use is discontinued until the replacement assembly is installed and tested. All replacement assemblies must be approved by the City and must be commensurate with the degree of hazard involved. A retest will be required following the replacement of the assembly. (Ord. 99-13, 9-21-1999)