A. Where required. An approved backflow prevention assembly shall also be installed on each service line to the customer system at or near the property line or immediately inside the building being served, but in all cases before the first branch line leading off the service line, wherever the following conditions exist:
1. In the case of premises having an auxiliary water supply which is not or may not be of safe bacteriological or chemical quality and which has not been accepted as an additional source by the city, the public water system shall be protected against backflow from the premises by installing an approved backflow prevention assembly in the service line appropriate to the degree of hazard.
2. In the case of premises on which any industrial fluids or any other objectionable substance is handled in such a fashion as to create an actual or potential hazard to the public water system, the public system shall be protected against backflow from the premises by installing an approved backflow prevention assembly in the service line appropriate to the degree of hazard. This shall include the handling of process waters and waters originating from the utility system which have been subject to deterioration in quality.
3. In the case of premises having internal cross-connection that cannot be permanently corrected or controlled; or intricate plumbing and piping arrangements or where entry to all portions of the premises is not readily accessible for inspection purposes, making it impracticable or impossible to ascertain whether or not dangerous cross-connections exist, the public water system shall be protected against backflow from the premises by installing an approved backflow prevention assembly in the service line.
4. In the event that the provisions of California Code of Regulations, Title 17 as the same may be amended from time to time or its successor provisions, pertaining to where backflow and cross-connection devices are required, mandate greater or more stringent requirements than as set forth in this § 13.16.040, then such provisions of said Title 17 pertaining thereto shall apply notwithstanding the provisions of this § 13.16.040.
('61 Code, § 24B.4)
B. Type required. The type of protective assembly required for the premises shall depend upon the degree of hazard which exists, as follows:
1. In the case of any premises where there is an auxiliary water supply as stated in paragraph A. above of this section and it is not subject to any of the following rules, the public water system shall be protected by an approved air-gap separation or an approved reduced pressure principle backflow prevention assembly.
2. In the case of any premises where there is water of a substance that would be objectionable but not hazardous to health, if introduced into the public water system, the public water system shall be protected by an approved double check valve assembly at each service connection.
3. In the case of any premises where there is any material dangerous to health which is handled in such a fashion as to create an actual or potential hazard to the public water system, the public water system shall be protected by an approved air-gap separation or an approved reduced pressure principle backflow prevention assembly at each service connection. Examples of premises where these conditions exist, include, but are not limited to, sewage treatment plants, sewage pumping stations, chemical manufacturing plants, hospitals, mortuaries and plating plants.
4. In the case of any premises where there are uncontrolled cross-connections, either actual or potential, the public water system shall be protected by an approved air-gap separation or an approved reduced pressure principle backflow prevention assembly at each service connection.
5. In the case of any premises where, because of security requirements or other prohibitions or restrictions, it is impossible or impractical to make a complete in-plant cross-connection survey, the public water system shall be protected against backflow from the premises by either an approved air-gap separation or an approved reduced pressure principle backflow prevention assembly on each service connection to the premises.
6. In the event that the provisions of California Code of Regulations, Title 17, as the same may be amended from time to time or its successor provisions, pertaining to the type of backflow and cross-connection devices required to be installed for a given degree of hazard, mandate a different or more stringent requirement for a given degree of hazard, then such provisions of said Title 17 pertaining thereto shall apply notwithstanding the provisions of this paragraph B.
('61 Code, § 24B.5)
C. Approval.
1. Any backflow prevention assembly required herein shall be a model and size approved by the Director. The term “approved backflow prevention assembly” shall mean an assembly that has been manufactured in full conformance with the standards established by the American Water Works Association entitled:
AWWA C506-84 Standards for Reduced Pressure Principle and Double Check Valve Backflow Prevention Devices; and that meets laboratory and field performance specifications of the Foundation for Cross-Connection Control and Hydraulic Research of the University of Southern California established by:
Specifications of Backflow Prevention
Assemblies § 10 of the most current
issue of the Manual of Cross-Connection
Control.
2. Said AWWA and FCCC&HR standards and specifications have been adopted by the Director. Final approval shall be evidenced by a “certificate of approval” issued by an approved testing laboratory certifying full compliance with said AWWA standards and FCCC&HR specifications.
3. The Director shall formulate a list of approved testing laboratories.
('61 Code, § 24B.6)
(Ord. 835, passed - - )