The following rules are to be used in conjunction with those rules contained in Title17 of the California Administrative Code and Section 12 of the Water Design and Construction Standards as well as the judgment of the Cross Connection Control Officer. These rules are aimed at protecting the City's water system near the water meter as opposed to internal protection within a building where such internal protection is provided and is approved by the City's Cross Connection Control Officer, protection at the meter may not be required.
(a) Requirement for devices. Any service connection to the public water system from a premises having a potential for harmful or objectionable substances to enter the public water system through backflow cross connections shall be protected.
(b) Auxiliary water supply. Whenever a building or premises has a connection to both the public water system and an auxiliary water supply, the latter shall be protected with either a reduced pressure device or a double check valve depending upon the potential and severity of the cross connection, unless the system was accepted by the City as an additional source of public system water.
(c) Air gaps. Are required at the service connection to any premises on which any material dangerous to health or toxic in nature may be handled under pressure. Also, air gaps shall be used to protect the potable system at wastewater treatment or pumping facilities. The air gap shall be located as close as practicable to the service cock. Other types of devices would only be approved if the air gap is not physically possible.
(d) Reduced pressure principle devices. Are required at industrial and/or commercial facilities using potentially harmful chemicals, hospitals, doctor's offices, irrigation systems (unless protected by air gap or pressure vacuum breaker), fire sprinkler systems using chemical additives, mortuaries, and as required by the Cross Connection Control Officer.
(e) Double check valve assemblies. Are required where products used within the building or premises might impact an objectionable taste, odor or color but would not be hazardous.
(f) Double check detector valves. Are required where there is no other meter between the water source and the building such as a fire service line for building.
(g) Whenever it is not practical to protect drinking water systems on premises against the entry of water from a source or piping system or equipment that cannot be approved as safe or potable for human use, an entirely separate potable water system shall be installed to supply water at points convenient for consumers.
(Ord. 1516-NS, eff. June 5, 2009)