Sonoma Municipal Code Ch. 13.20 Cross-Connections — Backflow Prevention

The purpose of these regulations is:

A. To protect the public water supply against actual or potential cross-connections by isolating within the premises contamination or pollution that may occur because of some undiscovered or unauthorized cross-connection on the premises;

B. To eliminate existing connections between drinking water systems and other sources of water that are not approved as safe and potable for human consumption;

C. To eliminate cross-connections between drinking water systems and other sources of water or process water used for any purpose whatsoever which jeopardize the safety of the drinking water supply;

D. To prevent the making of cross-connections in the future.

These regulations are in accordance with the state of California Department of Public Health Administrative Code, Title 17, entitled “Regulations Relating to Cross-Connections”.

It is the intent of these regulations to recognize that there are varying degrees of hazards and to apply the principle that the degree of protection should be commensurate with the degree of hazard. (Ord. 441 § 1, 1972).

The following words and phrases, whenever used in this chapter, shall have the meanings ascribed to them in this section:

A. “Air-gap separation” means a physical break between a supply pipe and a receiving vessel. The air-gap shall be at least double the diameter of the supply pipe, measured vertically above the top rim of the vessel, in no case less than one inch;

B. “Approved check valve” means a check valve that seats readily and completely and has been approved for use in this service by the city;

C. “Approved double check valve assembly” means an assembly which has been approved for use in this service by the city;

D. “Approved reduced pressure principle backflow prevention device” means a device which has been approved for use in this service by the city;

E. “Approved water supply” means any water supply approved by or under the public health supervision of a public health agency of the state of California, or its political subdivisions. In determining what constitutes an approved water supply, the State Department of Public Health reserves final judgment as to its safety and potability;

F. “Auxiliary supply” means any water supply on or available to the premises other than the public water supply;

G. “City” as used in this chapter means the public works director or his authorized representative;

H. “Cross-connection” as used in these regulations means any unprotected connection between any part of a water system used or intended to supply water for drinking purposes and any source or system containing water or substance that is not or cannot be approved as safe, wholesome, and potable for human consumption. (Ord. 441 § 2, 1972).

A. Each service connection from the public water system for supplying water to premises having an auxiliary water supply shall be protected against backflow of water from the premises into the public water system, unless the auxiliary water supply is accepted as an additional source by the water purveyor, and is approved by the public health agency having jurisdiction.

B. Each service connection from the public water system for supplying water to premises on which any substance is handled in such a fashion as to permit its entry into the water system shall be protected against backflow of the water from the premises into the public system. This shall include the handling of process waters and waters originating from the public water supply system which have been subject to deterioration in sanitary quality.

C. Backflow prevention devices shall be installed on the service connection to any premises that have internal cross-connections unless such cross-connections are abated to the satisfaction of the city and approved by the state or local health department. (Ord. 441 § 3, 1972).

The protective device required shall depend on the degree of hazard as tabulated below:

A. At the service connection to any premises where there is an auxiliary water supply handled in a separate piping system with no known cross-connection, the water supply shall be protected by an approved double check valve assembly;

B. At the service connection to any premises on which a substance that would be objectionable (but not necessarily hazardous to health), if introduced into the public water supply, is handled so as to constitute a cross-connection, the public water supply shall be protected by an approved double check valve assembly;

C. At the service connection on any premises on which there is an auxiliary water supply where cross-connections are known to exist which cannot be presently eliminated, the public water supply system shall be protected by an approved reduced pressure principle backflow prevention device. A double check valve assembly may be used in lieu of such device if local experience indicates that double check valves are reliably operated and if approved by the water purveyor and local health agency;

D. At the service connection to any premises on which any material dangerous to health or toxic substance in toxic concentration is or may be handled, the public water supply shall be protected by an air-gap separation. The air-gap shall be located as close as practicable to the service cock and all piping between the service cock and receiving tank shall be entirely visible. If these conditions cannot reasonably be met, the public water supply shall be protected with either an approved reduced pressure principle backflow prevention device, or an approved double check valve assembly, providing the alternative is acceptable to both the water purveyor and the local health agency;

E. At the service connection to any sewage treatment plant or sewage pumping station, the public water supply shall be protected by an air-gap separation. The air-gap shall be located as close as practicable to the service cock and all piping between the service cock and receiving tank shall be entirely visible. If these conditions cannot be reasonably met, the public water supply shall be protected with an approved reduced pressure principle backflow prevention device, providing this alternative is acceptable to both the water purveyor and local health agency. Final decision in this matter shall rest with the State Department of Public Health. (Ord. 441 § 4, 1972).

A. It shall be the responsibility of the city to make the determination if any service connection or the handling of substances within the premises served is deemed to constitute a hazard to the public water system and to determine the degree of hazard and establish the requirements for protection. The city shall accomplish this in conjunction with the local health agency.

B. It shall be the responsibility of the user of the water to install and maintain the required protective device as specified by the city and to have the device inspected and tested periodically by a person approved as qualified by the city. Inspection intervals shall be one year maximum. Required interval may be less if determined by the city that a history of malfunctioning has been established or if the degree of hazard makes more frequent inspections advisable. All devices shall be disassembled for maintenance and repair at least every five years. All test results and all maintenance steps taken shall be reported regularly on forms to be provided by the city and maintained on file at the city offices. Failure to file with the city the required test and maintenance reports will require the city to consider the connection unprotected and service may be discontinued. (Ord. 441 § 5, 1972).

Service of water to any premises may be discontinued by the city after reasonable notification if unprotected cross-connections exist on the premises, or if any defect is found in an installed backflow preventive device, or if a backflow preventive device has been removed or bypassed, and service will not be restored until such conditions or defects are corrected.

Discontinuance of service may be summary, immediate and without notice whenever, in the judgment of the public works director of the city, such action is necessary to protect the purity of the water supply or the safety of the water system, and the public works director’s determination shall be final and conclusive. (Ord. 441 § 6, 1972).

The city representative assigned to inspect premises relative to possible hazards shall carry proper credentials of his office, upon exhibition of which he has the right of entry, during usual business hours, to inspect any and all buildings and premises in the performance of his duty. This right of entry shall be a condition of water service in order to provide assurance that the continuation of service to the premises will not constitute a menace to the health, safety and welfare of the people throughout the public water system. (Ord. 441 § 7, 1972).

*For right of entry provisions, see Chapter 1.08 SMC.

Any person violating any provision of this chapter is guilty of a misdemeanor. Any person who is convicted of a violation of this chapter is guilty of a misdemeanor and shall be punished by a fine and/or penalty not to exceed the maximum as prescribed in the California Penal Code. (Ord. 441 § 9, 1972).