A. General Provisions.
1. It is unlawful for any person, firm or corporation at any time to make or maintain or cause to be made or maintained, temporarily or permanently, for any period of time whatsoever, any cross-connection between plumbing pipes of water fixtures being served with water by the city water department and any other source of water supply, or to maintain any sanitary fixture of other appurtenances or fixtures which by reason of their construction may cause or allow backflow of water or other substances into the water supply system of the city and/or the service of water pipes or fixtures of any water user of the city.
2. Unprotected cross-connections with the public water supply are prohibited.
3. Whenever the city engineer, health agency or local health agency determines that backflow protection is required on a premises, the city will require the water user to install an approved backflow prevention device at his/her expense for continued services or before a new service will be granted.
4. Wherever the city engineer, health agency or local health agency determines that backflow protection is required on a water supply line entering a water user's premises, then any and all water supply lines from the city's mains entering such premises, buildings or structures shall be protected by an approved backflow prevention device, to be installed at the water user's expense. The type of device to be installed will be in accordance with the requirements of this chapter.
5. Every fire protection system served by the water supplier shall be separately connected to the public water system, and not interconnected to plumbing systems serving domestic or irrigation water.
B. Where Protection is Required.
1. Each service connection from the city 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 city, and is approved by the public health agency having jurisdiction.
2. Each service connection from the city water system for supplying water to any premises on which any substance, which has the potential to create contamination, is handled in such fashion as may allow its entry into the water system, shall be protected against backflow of the water from the premises into the public system by a backflow prevention device to be installed at the water user's expense. Backflow prevention devices shall also be installed, at the water user's expense, for service connections handling process waters and waters originating from the city water system which have been subjected to contamination from the premises.
3. Backflow prevention devices shall be installed on all service connections to any premises having:
a. Internal cross-connections that cannot be permanently corrected and controlled to the satisfaction of the state or local health agency and the city engineer; or
b. Intricate plumbing and piping arrangements; or
c. 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 cross-connections exist.
4. Any system or premises designated to serve multiple commercial or industrial tenants whose water practices are unknown at the time the plumbing or building permit is issued shall be protected against backflow of water from the premises to the public water system by a backflow prevention device of the type required by the city engineer, health agency or local health agency. The determination of the type of backflow prevention device required shall be based on a determination of the potential hazard that may reasonably be expected to be encountered in buildings of similar type or nature.
5. All portable pressure spray or cleaning units (including water trucks, street sweepers, etc.) that have the capability of connecting to any water supplier's system shall be provided with an air-gap separation or a reduced pressure principle assembly.
C. Type of Protection Required.
1. The type of protection that shall be provided to prevent backflow into the approved water supply shall be commensurate with the degree of hazard that exists on the consumer's premises. The type of protective device that may be required (listed in an increasing level of protection) includes: double check-valve assembly (DC), reduced pressure principle backflow prevention device (RP) and an air-gap separation (AG). The water user may choose a higher level of protection than required by the city engineer, health agency or local health agency. The minimum type of backflow protection required to protect the approved water supply at the user's water connection to premises with varying degrees of hazard are given in Table 1. Situations which are not covered in Table 1 shall be evaluated on a case by case basis and the appropriate backflow protection shall be determined by the City Engineer or health agency, consistent with the highest practicable protection of potable water supplies.
TABLE 13.05.030 TYPE OF BACKFLOW PROTECTION REQUIRED | |
Degree of Hazard | Minimum Type of Backflow Prevention |
TABLE 13.05.030 TYPE OF BACKFLOW PROTECTION REQUIRED | |
Degree of Hazard | Minimum Type of Backflow Prevention |
(a) Sewage and Hazardous Substances. | |
(1) Premises where the public water system is used to supplement the reclaimed water supply. | AG |
(2) Premises where there are wastewater pumping and/or treatment plants and there is not interconnection with the potable water system. This does not include a single-family residence that has a sewage lift pump. A RP may be provided in lieu of an AG if approved by both the health agency and the city engineer | AG |
(3) Premises where reclaimed water is used and there is no interconnection with the potable water system. A RP may be provided in lieu of an AG if approved by both the health agency and the city engineer. | AG |
(4) Premises where hazardous substances are handled in any manner in which the substances may enter a potable water system. This does not include a single-family residence that has a sewage lift pump. A RP may be provided in lieu of an AG if approved by both the health agency and the city engineer. | AG |
(5) Premises where there are irrigation systems into which fertilizers, herbicides or pesticides are, or can be, injected or assimilated. | RP |
(b) Auxiliary Water Supplies. | |
(1) Premises where there is an unapproved auxiliary water supply which is interconnected with the public water system. A RP or DC may be provided in lieu of an AG is approved by both the health agency and the city engineer. | AG |
(2) Premises where there is an unapproved auxiliary water supply and there are no interconnections with the public water system. A DC may be provided in lieu of a RP if approved by both the health agency and city engineer. | RP |
(c) Fire Protection Systems. | |
(1) Premises where fire system is directly supplied from the public water system and there is an unapproved auxiliary water supply on or to the premises (not interconnected). | DC |
(2) Premises where the fire system is supplied from the public water system and interconnected with an unapproved auxiliary water supply. A RP may be provided in lieu of an AG if approved by both the health agency and city engineer. | AG |
(3) Premises where the fire system is supplied from the public water system and where either elevated storage tanks or fire pumps which take suction from the private reservoirs or tanks are used. | DC |
(d) Dockside Watering Points and Marine Facilities. | DC |
(1) Pier hydrants for supplying water to vessels for any purpose. | RP |
(2) Premises where there are marine facilities. | RP |
(e) Premises where entry is so restricted that the city engineer determines that inspections for cross-connections cannot be made with sufficient frequency or at sufficiently short notice to assure that cross-connections do not exist. | RP |
(f) Premises where cross-connections have been established or reestablished two or more times. | RP |
2. Two or more service connections supplying water from different street mains to the same building, structure or premises through which an interstreet main flow may occur, shall have at least a standard check-valve on each water service to be located adjacent to and on the property side of the respective meters. Such check-valve shall not be considered adequate if backflow protection is deemed necessary to protect the city's mains from pollution or contamination; in such cases the installation of approved backflow devices at such service connections shall be required.
(Ord. 89-09-1041 § 1 (part))