"Air-gap separation" or "AG"means the physical vertical separation of at least two times the effective opening, as defined in Section 207.0 of the California Plumbing Code, between the free-flowing discharge end of a supply pipeline and the flood level of an open or non-pressurized receiving vessel, and, in no case less than one inch.
"Approved"means accepted by the public works director or designee, as meeting an applicable specification stated or cited in this chapter, or as suitable for the proposed use.
"Auxiliary water supply"means any water supply on or available to the premises other than the purveyor's approved public potable water supply, that is either used or equipped, or can be equipped, to be used as a water supply. These auxiliary waters may include water from another purveyor's public potable water supply or any natural source(s) such as a well, spring, river, stream, harbor, etc., or "used waters" or "industrial fluids."
"Backflow"means an undesired or unintended reversal of flow of water and/or other liquids, gases, or other substances into the public water system distribution system or approved water supply.
"Backflow prevention assembly" or "BPA"means a mechanical assembly designed and constructed to prevent backflow, such that while in-line it can be maintained and its ability to prevent backflow, as designed, can be field tested, inspected and evaluated.
"Back-siphonage"means the flow of water or other liquids, mixtures or substances into the distributing pipes of a potable water supply system from any source other than its intended source caused by the sudden reduction of pressure in the potable water supply system.
"Contamination"means an impairment of the quality of the potable water by sewage, industrial fluids or waste liquids, compounds or other materials to a degree which creates an actual hazard to the public health through poisoning or through the spread of disease.
"Cross-connection"means any actual or potential connection or structural arrangement between the public water system, including a piping system connected to the public water system and located on the premises of a water user or available to the water user, and any source or distribution system containing liquid, gas, or other substances not from the approved water supply. Other types of cross-connections include connectors such as swing connections, removable sections, four-way plug valves, spools, dummy sections of pipe, swivel or changeover devices, sliding multiport tube, solid connections, etc.
"Cross-connection controlled"means a connection between a potable water system and a nonpotable water system with an approved BPA properly installed that will continuously afford the protection commensurate with the degree of hazard.
"Cross-connection control by containment"means the installation of an approved backflow prevention device at the water service connection to any customer's premises where it is physically and economically infeasible to find and permanently eliminate or control all actual or potential cross-connections within the customer's water system; or, it shall mean the installation of an approved backflow prevention device on the service line leading to and supplying a portion of a customer's water system where there are actual or potential cross-connections which cannot be effectively eliminated or controlled at the point of cross-connection.
"Double check detector backflow prevention assembly" or "DCDA"means a double check valve backflow prevention assembly that includes a bypass with a water meter and double check backflow prevention assembly, with the bypass's water meter accurately registering flow rates up to two gallons per minute and visually showing a registration for all rates of flow. This type of assembly may only be used to isolate low hazard cross connections.
"Double check valve backflow prevention assembly" or "DC"means an assembly of consisting of two independently-acting internally-loaded check valves, with tightly closing shut-off valves located on each end of the assembly (upstream and downstream of the two check valves) and fitted with test cocks that enable accurate field testing of the assembly. This type of assembly may only be used to isolate low hazard cross-connections. The entire assembly shall meet the design and performance specifications and approval of a recognized and city-approved testing agency for backflow prevention assembly. To be approved, these devices must be readily accessible for in-line maintenance and testing.
"Hazard assessment"means an evaluation of a user premises designed to evaluate the types and degrees of hazard at a user's premises.
"Hazard, degree of"is derived from a hazard assessment for the evaluation of potential risk to public health and the adverse effect of the hazard upon the potable water system.
"Hazard, health"means any condition, assembly or practice in the water supply system and its operation which could pose a danger to the health and well-being of the water consumer. An example of a health hazard is a structural defect, including cross-connections, in a water system.
"Hazard, plumbing"means a plumbing type cross-connection in a customer's potable water system that has not been properly protected by a vacuum breaker, air-gap separation or backflow prevention device. Unprotected plumbing type cross-connections are considered to be a health hazard.
"Hazard, pollutant"means an actual or potential threat to the physical properties of the water system or to the potability of the public or the consumer's potable water system but which would constitute a nuisance or be aesthetically objectionable or could cause damage to the system or its appurtenances, but would not be dangerous to health.
"Hazard, system"means an actual or potential threat of severe damage to the physical properties of the public potable water system or the consumer's potable water system or of a pollution or contamination which would have a protracted effect on the quality of the potable water in the system.
"High hazard cross-connection"means a cross-connection that poses a threat to the potability or safety of the public water supply. Materials entering the public water supply through a high hazard cross-connection are contaminants or health hazards.
"Industrial fluids system"means any system containing a fluid or solution which may be chemically, biologically or otherwise contaminated or polluted in a form or concentration such as would constitute a health, system, pollutional or plumbing hazard if introduced into an approved water supply. This may include, but not be limited to: polluted or contaminated waters; all types of processed waters and "used waters" originating from the public potable water system which may have deteriorated in sanitary quality; chemicals in fluid form; plating acids and alkalis, circulated cooling waters connected to an open cooling tower and/or cooling towers that are chemically or biologically treated or stabilized with toxic substances; contaminated natural waters such as from wells, springs, streams, rivers, bays, harbors, seas, irrigation canals or systems, etc.; oils, gases, glycerine, paraffins, caustic and acid solutions and other liquid and gaseous fluids used in industrial or other purposes or for firefighting purposes.
"Low hazard cross-connection"means a cross-connection that has been found to not pose a threat to the potability or safety of the public water supply but may adversely affect the aesthetic quality of the potable water supply. Materials entering the public water supply through a low hazard cross-connection are pollutants or non-health hazards.
"Pollution"means the presence of any foreign substance (organic, inorganic, or biological) in water which tends to degrade its quality so as to constitute a hazard or impair the usefulness or quality of the water to a degree which does not create an actual hazard to the public health but which does adversely and unreasonably affect such waters for domestic use.
"Public works director."Head of the engineering, environmental services, and utilities divisions of the city is invested with the authority and responsibility for the implementation of an effective cross-connection control program and for the enforcement of the provisions of this chapter.
"Reduced pressure principle backflow prevention assembly" or "RP"means an assembly with-two independently acting internally-loaded check valves, with a hydraulically operating mechanically independent differential-pressure relief valve located between the check valves and below the upstream check valve. The assembly shall have shut-off valves located upstream and downstream of the two check-valves, and test cocks to enable accurate field testing of the assembly. The entire assembly shall meet the design and performance specifications and approval of a recognized and city-approved testing agency for backflow prevention assemblies. The device shall operate to maintain the pressure in the zone between the two check valves at a level less than the pressure on the public water supply side of the device. At cessation of the normal flow the pressure between the two check valves shall be less than the pressure on the public water supply side of the device. In case of leakage of either of the check valves the differential relief valve shall operate to maintain the reduced pressure in the zone between the check valves by discharging to the atmosphere. When the inlet pressure is two pounds per square inch or less, the relief valve shall open to the atmosphere. To be approved, these devices must be readily accessible for in-line maintenance and testing and be installed in an above-ground location where no part of the device will be submerged.
"State Water Board"means the State Water Resources Control Board or the local primacy agency having been delegated the authority to enforce the requirements of the CCCPH by the State Water Resources Control Board.
"Water, nonpotable"means water which is not safe for human consumption or which is of questionable potability.
"Water, potable"means any water which, according to recognized standards, is safe for human consumption.
"Water service connections"means the terminal end of a service connection from the public potable water system; i.e., where the water purveyor loses jurisdiction and sanitary control over the water at its point of delivery to the customer's water system. If a meter is installed at the end of the service connection, then the service connection shall mean the downstream end of the meter. There should be no unprotected takeoffs from the service line ahead of any meter or backflow prevention device located at the point of delivery to the customer's water system. "Service connection" shall also include water service connection from a fire hydrant and all other temporary or emergency water service connections from the public potable water system.
"Water, used"means any water supplied by a water purveyor from a public potable water system to a consumer's water system after it has passed through the point of delivery and is no longer under the sanitary control of the water purveyor.
(Prior code § 2-16.49; Ord. 2000 § 1, 2009; Ord. 2296, 7/15/2025)