The purpose of this chapter is:
(A) To protect the public potable water supply of the city from the possibility of contamination or pollution by isolating within its customers' internal distribution systems such contaminants or pollutants which could backflow or back-siphon into the public water supply system;
(B) To promote the elimination or control of existing cross-connections, actual or potential, between its customers' in-plant potable water systems and nonpotable water systems, plumbing fixtures, and industrial piping systems; and
(C) To provide for the maintenance of a continuing program of cross-connection control which will systematically and effectively prevent the contamination or pollution of all potable water systems.
('66 Code, § 6-7.01) (Ord. 262-C-S, passed 10-10-74)
The City Engineer shall be responsible for the protection of the public potable water distribution system from contamination or pollution due to the backflow or back-siphonage of contaminants or pollutants through the water service connection. If, in the judgment of the City Engineer, an approved backflow prevention device is required at the city's water service connection to any customer's premises for the safety of the water system, the City Engineer or his designated agent shall give notice in writing to such customer to install such an approved backflow prevention device at each service connection to his premises. The customer shall immediately install such approved device, at his own expense, and failure, refusal, or inability on the part of the customer to install such device immediately shall constitute a ground for discontinuing water service to the premises until such device has been properly installed.
('66 Code, § 6-7.02) (Ord. 262-C-S, passed 10-10-74)
For the purpose of this chapter, the following definitions shall apply unless the context clearly indicates or requires a different meaning.
AIR-GAP. The unobstructed vertical distance through the free atmosphere between the lowest opening from any pipe or faucet supplying water to a tank, plumbing fixture, or other device and the flood level rim of such vessel. An approved air-gap shall be at least double the diameter of the supply pipe and, in no case, less than one inch. When an air-gap is used at the service connection to prevent the contamination or pollution of the public potable water system, an emergency bypass shall be installed around the air-gap system, and an approved reduced pressure principle device shall be installed in the bypass system.
APPROVED. Accepted by the City Engineer as meeting an applicable specification stated or cited in this chapter, or as suitable for the proposed use.
AUXILIARY WATER SUPPLY. Any water supply on or available to the premises other than the purveyor's approved public potable water supply. These auxiliary waters may include water from another purveyor's public potable water supply or any natural source, such as a well, spring, river, stream, harbor, and the like, or “used waters” or “industrial fluids.” These waters may be polluted or contaminated or they may be objectionable and constitute an unacceptable water source over which the water purveyor does not have sanitary control.
BACKFLOW. The flow of water or other liquids, mixtures, or substances under pressure into the distributing pipes of a potable water supply system from any source other than its intended source.
BACK-SIPHONAGE. 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.
BACKFLOW PREVENTER. A device or means designed to prevent backflow or back-siphonage.
CONTAMINATION. 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. Any physical connection or arrangement of piping or fixtures between two otherwise separate piping systems, one of which contains potable water and the other nonpotable water or industrial fluids of questionable safety, through which, or because of which, backflow or back-siphonage may occur into the potable water system. A water service connection between a public potable water distribution system and a customer's water distribution system which is cross-connected to a contaminated fixture or industrial fluid system or with a potentially contaminated supply or auxiliary water system constitutes one type of cross-connection. Other types of cross-connections include connectors, such as swing connections, removable sections, four-way plug valves, spools, dummy sections of pipe, swivel or change-over devices, sliding multiport tubes, solid connections, and the like.
CROSS-CONNECTION, CONTROLLED. A connection between a potable water system and a nonpotable water system with an approved backflow prevention device properly installed that will continuously afford the protection commensurate with the degree of hazard.
CROSS-CONNECTION CONTROL BY CON-TAINMENT. 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.
CITY ENGINEER. The City Engineer of the city.
DOUBLE CHECK VALVE ASSEMBLY. An assembly of two independently operating approved check valves with tightly closing shutoff valves on each side of the check valves, plus properly located test cocks for the testing of each check valve. The entire assembly shall meet the design and performance specifications and approval of a recognized and city approved testing agency for backflow prevention devices. To be approved these devices shall be readily accessible for in-line maintenance and testing.
HAZARD, DEGREE OF. The elevation of the potential risk to public health and the adverse effect of the hazard upon the potable water system as:
(1)
HAZARD, HEALTH. Any condition, device, or practice in the water supply system and its operation which could create, or, in the judgment of the City Engineer, may create, 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 supply system.
(2)
HAZARD, PLUMBING. A plumbing type cross-connection in a consumer'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 shall be considered to be health hazards.
(3)
HAZARD, POLLUTIONAL. 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.
(4)
HAZARD, SYSTEM. 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.
INDUSTRIAL FLUIDS SYSTEM. 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 process 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 alkalies; 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, and the like; and oils, gases, glycerine, paraffins, caustic and acid solutions, and other liquid and gaseous fluids used for industrial or other purposes or for fire-fighting purposes.
POLLUTION. 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.
REDUCED PRESSURE PRINCIPLE DEVICE. An assembly of two independently operating approved check valves with an automatically operating differential relief valve between the two check valves, tightly closing shut-off valves on either side of the check valves, plus properly located test cocks for the testing of the check and relief valves. 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 the 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 open to the atmosphere. To be approved these devices shall be readily accessible for in-line maintenance and testing and be installed in a location where no part of the device will be submerged.
WATER, POTABLE. Any water which, according to recognized standards, is safe for human consumption.
WATER, NONPOTABLE. Water which is not safe for human consumption or which is of question-able potability.
WATER SERVICE CONNECTION. 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. WATER SERVICE CONNECTION shall also include the water service connection from a fire hydrant and all other temporary or emergency water service connections from the public potable water system.
WATER, USED. 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.
('66 Code, § 6-7.03) (Ord. 262-C-S, passed 10-10-74)
(A) Water system.
(1) The water system shall be considered as made up of two parts, the city system and the customer system.
(2) The city system shall consist of the source facilities and the distribution system and shall include all those facilities of the water system under the complete control of the city, from the source of supply up to the point where the customer's system begins. The source shall include all components of the facilities utilized in the production, treatment, storage, and delivery of water to the distribution system.
(3) The distribution system shall include the network of conduits used for the delivery of water from the source to the customer's system.
(4) The customer's system shall include those parts of the facilities beyond the termination of the city distribution system which are utilized in conveying city-delivered domestic water to points of use.
(B) Policy.
(1) No water service connection to any premises shall be installed or maintained by the water purveyor unless the water supply is protected as required by state laws and the provisions of this chapter. Service of water to any premises shall be discontinued by the water purveyor if a backflow prevention device required by state law or by the provisions of this chapter is not installed, tested, and maintained, or if it is found that a back-flow prevention device has been removed or bypassed, or if an unprotected cross-connection exists on the premises. Service will not be restored until such conditions or defects are corrected.
(2) The customer's system should be open for inspection at all reasonable times to authorized representatives of the Maintenance Services Department to determine whether cross-connections or other structural or sanitary hazards, including violations of the provisions of this chapter, exist. When such a condition becomes known, the Director of Maintenance Services shall deny or immediately discontinue service to the premises by providing for a physical break in the service line until the customer has corrected the condition in conformance with state and city laws relating to plumbing and water supplies and the regulations adopted pursuant thereto.
(3) An approved backflow prevention device shall also be installed on each service line to a customer's water system at or near the property line or immediately outside the building being served but, in all cases, before the first branch line leading off the service line, wherever the following conditions exist:
(a) 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 is not acceptable as an additional source by the Director of Community Development, the public water system shall be protected against backflow from the premises by installing a backflow prevention device in the service line appropriate to the degree of hazard.
(b) In the case of premises on which any industrial fluid 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 a backflow prevention device in the service line appropriate to the degree of hazard. This shall include the handling of process waters and waters originating from the city systems which have been subject to deterioration in quality.
(c) In the case of premises having any internal cross-connection that cannot be permanently corrected and 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 a backflow prevention device in the service line.
(4) The type of protective device required pursuant to the provisions of subdivisions (a), (b), and (c) of subdivision (3) of this division shall depend upon the degree of hazard which exists as follows:
(a) In the case of any premises where there is an auxiliary water supply as set forth in subdivision (3)(a) of this division, which is not otherwise subject to the provisions of this chapter, the public water system shall be protected by an approved air-gap separation or an approved reduced pressure principle backflow.
(b) In the case of any premises where there is any water or 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.
(c) 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 device. Examples of premises where these conditions will exist include sewage treatment plants, sewage plumbing stations, chemical manufacturing plants, hospitals, mortuaries, and plating plants.
(d) 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 device at the service connection.
(e) In the case of any premises where, because of security requirements or other prohibitions or restrictions, it is impossible or impracticable to make a complete in-plant cross-connection survey, the public water system shall be protected against backflow or back-siphonage from the premises by the installation of a backflow prevention device in the service line. In this case, maximum protection will be required; that is, an approved air-gap separation or an approved reduced pressure principle backflow prevention device shall be installed in each service to the premises.
(5) The following specific types of uses and other uses as designated by the City Engineer shall be required to install a backflow prevention device of the type indicated as a minimum:
Uses Type of Devices
Auxiliary water systems:
Interconnected Reduced pressure
Not interconnected Double check valve
Beverage bottling plants Double check valve
Buildings with booster pump
systems and/or water storage
tanks Double check valve
Canneries, packinghouses, and
reduction plants Reduced pressure
Buildings with sewage ejectors Air-gap separation
Car washes Reduced pressure
Chemical processing or storage
facilities Reduced pressure
Laundries Reduced pressure
Dairies Double check valve
Dye works Reduced pressure
Film processing laboratories Reduced pressure
Fire systems:
No auxiliary supply Double check valve
Auxiliary supply Reduced pressure
Frozen food processing plants Reduced pressure
Schools:
Lab facility/auxiliary supply Reduced pressure
No lab facility/no auxiliary supply Double check valve
Lab facility/no auxiliary supply Double check valve
No lab facility/auxiliary supply Reduced pressure
Hospitals Reduced pressure
Mortuaries and medical/dental
buildings Reduced pressure
Irrigation systems (all) Double check valve
Laboratories, commercial Reduced pressure
Manufacturing or processing
using toxic materials Reduced pressure
Mobile home parks Double check valve
Multi-story buildings
(3 or more stories) Double check valve
Oil or gas production facilities Reduced pressure
Pulp and paper processing Reduced pressure
Plating plants Reduced pressure
Sand and gravel plants Double check valve
Sewage and storm drain pumping
facilities Air-gap separation
Swimming pools Reduced pressure
Boat docks and marinas Reduced pressure
Tank trucks using hydrant
supply Double check valve
Portable insecticide and
herbicide spray tanks Air-gap separation
(6) (a) Any backflow prevention device required by the provisions of this chapter shall be of a model and size approved by the City Engineer. The term
APPROVED BACKFLOW PREVENTION DEVICE shall mean a device that has been manufactured in full conformance with the standards established by the American Water Works Association entitled “AWWA C506-69 Standards for Reduced Pressure Principle and Double Check Valve Backflow Prevention Devices” and which has met completely the laboratory and field performance specifications of the Foundation for Cross-Connection Control and Hydraulic Research of the University of Southern California established by the “Specifications of Backflow Prevention Devices - #69-2” dated March, 1969, or the most current issue.
(b) Said AWWA and FCCC&HR standards and specifications have been adopted by the City Engineer. The final approval of any device or system proposed for installation pursuant to the provisions of this chapter 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.
(c) The following testing laboratory has been qualified by the Director of Community Development to test and certify backflow preventers:
Foundation for Cross-Connection Control and Hydraulic Research
University of Southern California
University Park
Los Angeles, California 90007
(d) Testing laboratories other than the laboratory listed above will be added to an approved list as they are qualified by the City Engineer.
(e) Backflow preventers which may be subjected to back pressure or back-siphonage and which have been fully tested and granted a certificate of approval by such qualified laboratory and are listed on the laboratory's current list of “approved devices” may be used without further test or qualification.
(7) It shall be the duty of the city at any premises where backflow prevention devices are installed to have a certified inspection or operational test made at least once each year. In those instances where the City Engineer deems the hazard to be great enough, he may require certified inspections at more frequent intervals. These inspections and tests may be at the expense of the water user and shall be performed by the device manufacturer's representa-tive, by the Maintenance Services Department personnel, or by a certified tester approved by the City Engineer. It shall be the duty of the Director of Maintenance Services to see that these timely tests are made. The customer-user shall be notified by the Director of Maintenance Services in advance when the tests are to be undertaken so that he or his representative may witness the tests if it is so desired. Those devices found to be defective shall be repaired, overhauled, or replaced at the expense of the customer-user. Records of such tests, repairs, and overhaul shall be kept by the Maintenance Services Department.
(8) All presently installed backflow prevention devices which do not meet the require-ments of this section but were approved devices for the purposes described in this chapter at the time of their installation and which have been properly maintained shall, except for the inspection and maintenance requirements of subdivision (6) of this division, be excluded from the requirements of these rules so long as the City Engineer is assured that they will satisfactorily protect the city system. Whenever the existing device is moved from the present location or requires more than minimum maintenance, or when the Director of Maintenance Services finds that the continued maintenance of such device constitutes a hazard to health, the unit shall be replaced by a backflow prevention device meeting the requirements of this section at the expense of the customer-user.
(C) The City Engineer is hereby authorized and empowered to enforce the provisions of this chapter.
('66 Code, § 6-7.04) (Ord. 262-C-S, passed 10-10-74) Penalty, see §§ 1-2.01 et seq.