Chapter 8.10
BACKFLOW AND CROSS-CONNECTION CONTROL PROGRAM
Sections:
8.10.030 Requirements of program.
8.10.040 Consumer’s duty to test backflow prevention assemblies.
8.10.050 Existing backflow prevention assemblies.
8.10.060 City’s promulgation of rules and policies.
Prior history: 1966 Code §§ 6025, 6027, 6028, 6029, 6030 was amended by Ord. 371.
8.10.010 Purposes.
The city council finds and declares the purposes of this chapter as follows:
A. To protect the public potable water supply of the city of Millbrae from the possibility of contamination or pollution by isolating within the consumer’s internal distribution system(s) or the consumer’s private water system(s) such contaminants or pollutants which could backflow into the public water system; and
B. To promote the elimination or control of existing cross-connections, actual or potential, between the consumer’s in-plant potable water system(s) and non-potable water system(s), plumbing fixtures and industrial piping system(s); and
C. To maintain a continuing cross-connection control program which will systematically and effectively prevent the contamination or pollution of all potable water systems; and
D. To establish that the state health official shall be responsible for the protection of the public potable water system from contamination or pollution due to the backflow of contaminants or pollutants through the water service connection. If, in the judgment of said state health official, an approved backflow prevention assembly is required (at the consumer’s water service connection or within the consumer’s private water system) for the safety of the water system, the state health official or his designated agent shall give notice in writing to said consumer to install such an approved backflow protection assembly(s) at a specific location(s) on his premises. The consumer shall immediately install such an approved backflow prevention assembly(s) at the consumer’s own expense; and, failure, refusal or inability on the consumer to install, have tested and maintained said assembly(s) shall constitute grounds for discontinuing water service to the premises until such requirements have been satisfactorily met. (Ord. 689, § 1; 1976 Code § 8-2.01).
8.10.020 Definitions.
“Approved” as used in this chapter in reference to a water supply, means a water supply that has been approved by the state health official having jurisdiction. In reference to an air gap, a double check valve assembly, a reduced pressure principle backflow prevention assembly or other backflow prevention assemblies or methods shall mean an approval by the health officer.
“Approved backflow prevention assembly (See definition below of backflow prevention assembly)” means an assembly that has been manufactured in full conformance with standards established by the American Water Works Association (AWWA) entitled “AWWA/ANSI C510-92 standard for double check valve backflow prevention assemblies” and “AWWA/ANSI C511-92 standard for reduced pressure principle backflow prevention assemblies;” and, have met completely the laboratory and field performance specifications of the University of Southern California Foundation for cross-connection control and hydraulic research (USC FCCCHR). Said AWWA and USC FCCCHR standards and specifications have been adopted by the city of Millbrae and the department of health services.
“Auxiliary water supply” means any water supply on or available to the premises other than the purveyor’s approved public water supply will be considered as an “auxiliary water supply.” These auxiliary waters may include water from another purveyor’s potable water supply or any natural sources such as well, spring, river, stream, etc., or used waters or industrial fluids. These waters may be contaminated or polluted or they may be objectionable and constitute an unacceptable water source over which the water purveyor does not have sanitary control.
“Backflow” means the undesirable reversal of flow of water or mixtures of water and other liquids, gases or other substances into the distribution pipes of the potable water supply of water from any source or sources.
“Backflow prevention assembly” means an assembly or means designed to prevent backflow. Such means are described as the following:
1. “Air gap” means a physical separation between the free flowing discharge end of a potable water system supply pipeline and an open or non-pressure receiving vessel. An approved air gap shall be at least double the diameter of the supply line measured vertically above the overflow rim of the vessel in no case less than one inch.
2. “Reduced pressure principle backflow prevention assembly” means a device containing two independently acting approved check valves together with hydraulically operating, mechanical independent pressure differential relief valve located between the check valves and at the same time below the first check valve. The unit shall include properly located resilient seated test cocks and tightly closing resilient seated shutoff valves at each end of the assembly. This assembly is designed to protect against a non-health hazard (pollutant) or a health hazard (contaminant). This assembly shall not be used for backflow protection of sewage or reclaimed water.
3. “Double check valve backflow prevention assembly” means an assembly composed of two independently acting, approved check valves, including tightly closing resilient seated shutoff valves attached at each end of the assembly and fitted with properly located resilient seated test cocks. This assembly shall be only used to protect against a non-health hazard (pollutant).
“Backpressure” means any elevation of pressure in the downstream piping system above the supply pressure at a point of consideration which would cause, or tend to cause, a reversal of the normal direction of flow.
“Backsiphonage” means a form of backflow due to the reduction in system pressure which causes sub-atmospheric pressure to exist at a site in the water system.
“City” means the city of Millbrae.
“Consumer” means any resident or business located in the city of Millbrae who uses or consumes water.
“Consumer’s system” consists of those parts of the facilities beyond the termination of the water purveyor’s distribution system which are utilized in conveying potable water to point of use.
“Contamination” means an impairment of the quality of water which creates an actual hazard to the public health through poisoning or through the spread of disease by sewage, industrial fluids, waste, or similar means.
“Cross-connection” means any unprotected actual or potential connection or structural arrangement between a public or a consumer’s potable water system and any other source or system through which it is possible to introduce into any part of the potable water system any used water, industrial fluid, gas, or substance other than the intended potable water with which the system is supplied. Bypass arrangements, jumper connections, removable sections, swivel or change-over devices, and other temporary or permanent devices through which or because of which backflow can or may occur are considered to be cross-connections.
“Degree of hazard” means either a pollutant (nonhealth) or contamination (health) hazard and is derived from the evaluation of conditions within a system.
1. “Health hazard” means an actual or potential threat of contamination of a physical or toxic nature to the public potable water system or the consumer’s potable water system that would be a danger to health.
2. “Plumbing hazard” means an internal or plumbing type cross-connection in a consumer’s potable water system that may be a pollution or contamination type hazard. This includes but is not limited to cross-connections to toilets, sinks, lavatories, wash trays, and lawn sprinkling systems. Plumbing type cross-connections can be located in homes, apartment houses, hotels and commercial or industrial establishments. Such a connection, if permitted to exist, must be properly protected by an appropriate type of backflow prevention assembly.
“Health officer” means the city of Millbrae 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, and shall be deemed the health officer.
“Industrial fluids” means any fluid or solution which may be chemically, biologically or otherwise contaminated or polluted in a form or concentration which 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 used waters; all types of process waters; and, used waters originating from the potable water supply, which may deteriorate in sanitary quality.
“Pollution” means an impairment of the quality of water to a degree which does not create a hazard to the public health but which does adversely and unreasonably affect the aesthetic qualities of such waters for domestic use.
“Potable water” means any public water supply which has been investigated and approved by the health agency.
“Service connection” means the terminal end of a service connection from the public potable water system. If a water meter is installed at the end of the service connection, then the service connection shall mean the downstream end of the water meter.
“State health official” is in charge of the San Mateo Environmental Health Cross-Connection Control Program. The state health official is any authorized representative from the San Mateo Environmental Health Cross-Connection Control Program.
“Used water” means any water supplied by a water purveyor from public potable water system to consumer’s water system after it has passed through the service connection and is no longer under the control of the water purveyor.
“Water purveyor” is defined as the city of Millbrae.
“Water purveyor’s system” refers to the source facilities and the distribution system of the city and shall include all those facilities of the water system under the complete control of the water purveyor up to the point where the consumer’s system begins. The source facilities shall include all components of the facilities utilized in the production, treatment, storage, and delivery of water to the distribution system. The distribution system shall include the network of conduits used for the delivery of water from the source to the consumer’s system. (Ord. 689, § 1; 1976 Code § 8-2.02).
8.10.030 Requirements of program.
A. No water service connection to any premises will be installed or maintained by the water purveyor unless the water supply is protected as required by the department of health services, San Mateo County, any and all applicable laws and regulations, and this chapter. Service of water to any premises shall be discontinued by the water purveyor if the backflow prevention assembly required by this chapter is not installed, tested and maintained, or if it is found that the backflow prevention assembly has been removed, bypassed, or if an unprotected cross-connection exists on the premises. Service will not be restored until such conditions or defects are corrected.
B. The consumer’s system must be open for inspection at all reasonable times to authorized representatives of the city and department of health services, to determine whether unprotected cross-connections or other structural or sanitary hazards, including violations of these regulations, exist. When such a condition becomes known, the city and/or the department of health services representative will deny or immediately discontinue service to the premises by a physical break in the service line until the consumer has corrected the condition(s) and is in full conformance with this chapter.
C. An approved backflow prevention assembly must also be installed on each service line to the consumer’s system at or near the property line or immediately inside the building being served but, in all cases, before the first branch leading off the service line wherever the following conditions exist:
1. 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 city, the water purveyor’s system shall be protected against backflow from the premises by installing an approved backflow prevention assembly in the service line commensurate with the degree of hazard.
2. In the case of premises on which any industrial fluids or any objectionable substance is handled in such a fashion 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 an approved backflow prevention assembly in the service line commensurate with the degree of hazard. This shall include the handling of process waters and waters originating from the water purveyor’s system which have been subject to deterioration of quality.
3. In the case of premises having internal cross-connections that cannot be permanently corrected or protected against, or where intricate plumbing and piping arrangements exist, 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 an approved backflow prevention assembly in the service line.
D. The type of protective assembly required will depend upon the degree of hazard which exists as follows:
1. In the case of any premises where there is an auxiliary water supply as defined in MMC 8.10.020, the water purveyor’s system shall be protected by an approved air gap or an approved reduced pressure principle backflow prevention assembly.
2. In the case of any premises where there is water or substance that would be objectionable but not hazardous to health if introduced to the water purveyor’s system, the water purveyor’s system shall be protected by an approved double check valve backflow prevention assembly.
3. In the case of any premises where there is any material danger to health which is handled in such a fashion as to create an actual or potential hazard to the water purveyor’s system, the water purveyor’s system shall be protected by an approved air gap or approved reduced pressure principle backflow prevention assembly. Examples of premises where these conditions will exist include sewage treatment plants, sewage pumping stations, chemical manufacturing plants, hospitals, mortuaries and plating plants.
4. In the case of any premises where there is unprotected cross-connections, either actual or potential, the water purveyor’s system shall be protected by an approved air gap or an approved reduced pressure principle backflow prevention assembly at the service connection.
5. In the case of any premises where, because of security requirements or other prohibitions or restrictions, it is impossible or impractical to make a complete in-plant cross-connection survey, the water purveyor’s system shall be protected against backflow from the premises by either an approved air gap or an approved reduced pressure principle backflow prevention assembly on each service to the premises.
E. Any backflow prevention assembly required herein shall be a make, model, and size approved by the city or the department of health services and comply with the definition of approved backflow prevention assembly in MMC 8.10.020. (Ord. 689, § 1; 1976 Code § 8-2.03).
8.10.040 Consumer’s duty to test backflow prevention assemblies.
It shall be the duty of the consumer at any premises where backflow prevention assemblies are installed to have a field test performed by a certified backflow prevention assembly tester once upon installation and once a year. In those instances where the city or the department of health services deems the hazard to be great enough, field tests may be required at more frequent intervals. These tests shall be at the expense of the water user and shall be performed by a certified tester approved by the city or the department of health services. It shall be the duty of the health officer to see that these tests are made in a timely manner. The consumer shall notify the health officer in advance when the tests are to be undertaken so that the official representative may witness the field tests if so desired. Records of such tests, repairs, and overhaul will be kept and made available to the health officer. Records of such test shall also be available at the department of health services. (Ord. 689, § 1; 1976 Code § 8-2.04).
8.10.050 Existing backflow prevention assemblies.
All presently installed backflow prevention assemblies which do not meet the requirements of this section but were approved devices for the purposes described herein at the time of the installation and which have been properly maintained, will be excluded from the requirements of this chapter, except for the testing and maintenance requirements, so long as the health officer is assured that they will satisfactorily protect the water purveyor’s system. Whenever the existing device is moved from the present location or requires more than the minimum maintenance or when the health officer finds that the maintenance constitutes a hazard to health, the unit will be replaced by an approved backflow prevention assembly meeting the requirements of this chapter. (Ord. 689, § 1; 1976 Code § 8-2.05).
8.10.060 City’s promulgation of rules and policies.
The city is authorized to make all necessary and reasonable rules and policies in full compliance with the rules and regulations of the department of health services concerning cross-connection control with respect to the enforcement of this chapter. All such rules shall be consistent with the provisions of this chapter and shall be effective thirty days after being filed with the city clerk of the city of Millbrae. (Ord. 689, § 1; 1976 Code § 8-2.06).