Gilroy Municipal Code Art. V Water System Backflow Prevention

(a) Title 17, Chapter V, Sections 7583 through 7622, inclusive of the California Administrative Code, entitled “Regulations Relating to Cross-Connections,” sets forth rules and regulations governing cross-connections.

(b) Title 17, Section 7583 of the California Administrative Code, states among other things, “The water purveyor has primary responsibility to prevent water from unapproved sources, or any other substance, entering the public water supply system.” The city is a water purveyor within the meaning of Title 17.

(c) In order to provide for an orderly and adequate means of protection of the city’s water distribution system from backflow, the requirements set forth in this article are reasonable and necessary. The city adopts these requirements for the protection of the city’s water distribution system from backflow. New water service connections shall be installed and existing water connections shall be modified to conform to these requirements as set forth in this article.

(Ord. No. 88-8, § 1, 6-6-1988)

The regulations of the California Department of Health, Title 17, California Administrative Code, Sections 7583 through 7622 inclusive, referred to in this article as Title 17 and any amendments thereto, are hereby adopted, incorporated by reference and made a part of this chapter, insofar as the same are applicable to the protection to the city’s water distribution system.

(Ord. No. 88-8, § 1, 6-6-1988; Ord. No. 92-4, § 1, 4-6-1992)

Words used in this article, unless the context requires otherwise, are defined as follows:

(a)

“Air-gap separation (A-G)”

means a physical break where a pipe or hose is connected to or discharged into a vessel or conduit, provided that the break is at least double the diameter of the pipe, measured vertically above the rim of the receiving vessel or conduit and in no case less than one inch.

(b)

“Atmospheric vacuum breaker (AVB)”

means a vacuum breaker designed and used so as not to be subject to continuous static line pressure.

(c)

“Auxiliary water supply”

means any water supply on, or available to, the premises other than water supplied by the city.

(d)

“Backflow”

means the reverse flow of water or any other fluid or substance or any combination or any mixture thereof from the customer’s system into the city’s water distribution system.

(e)

“Backflow prevention device”

means a device which will prevent backflow into the city’s water distribution system.

(f)

“Certified tester”

means a person who is certified as a backflow prevention device tester by the city.

(g)

“City”

means the City of Gilroy, California.

(h)

“City’s water distribution system”

means the water main distribution system owned and operated by the city including the service from the main to and including the water meter.

(i)

“Contamination”

means an impairment of the potable water supply by any foreign substance.

(j)

“Critical level (C-L)”

means the marking on a backflow preventor at a point which determines the minimum elevation above the flood level rim of the fixture or receptacle served at which the device may be installed. When a backflow preventer does not bear a critical level marking, the bottom of the device shall constitute the critical level.

(k)

“Cross-connection,”

as used in this article, means any unprotected actual or significant potential connection between a potable water system used to supply water for drinking purposes and any source or system containing unapproved water or a substance that is not or cannot be approved as safe, wholesome, and potable. Bypass arrangements, jumper connections, removable sections, swivel or changeover assemblies, or other assemblies through which backflow could occur, shall be considered to be cross-connections.

(l)

“Customer”

means any person or organization who receives water from the city.

(m)

“Customer’s system”

means the water piping system located immediately downstream from a meter.

(n)

“Director of public works”

means the director of public works for the city or his designate.

(o)

“Double check valve (DC)”

means a back-flow preventor consisting of an assembly of at least two (2) independently acting approved check valves, including tightly closing shutoff valves on each side of the check valve assembly and connections available for testing the water tightness of each check valve.

(p)

“Health agency”

means the health authority (state, county, or local) having jurisdiction.

(q)

“Industrial fluid”

means any fluid or solution which could create a contamination if introduced into a potable water system.

(r)

“Potable water”

means water that is suitable, safe, or prepared for drinking.

(s)

“Premises”

means a piece of land together with such buildings and appurtenances located thereon.

(t)

“Pressure vacuum breaker (PVB)”

means a vacuum breaker designed to operate under conditions of static line pressure.

(u)

“Reduced pressure principle device (RP)”

means a backflow preventer that:

(1)

Incorporates two (2) or more internally loaded check valves, an automatically operating differential relief valve located between the two (2) check valves, two (2) shut-off valves, and necessary appurtenances for testing.

(2)

Maintains pressure in the zone between the two (2) check valves less than the pressure on the public water system side of the device.

(3)

Maintains the reduced pressure between the check valves in case of leakage of either check valve by discharging to the atmosphere.

(4)

Opens the relief valve to atmosphere to provide an air-gap separation in the backflow preventer when the inlet pressure is two (2) pounds per square inch or less.

(v)

“Service connection”

means the water piping system connecting the customer’s system with the city’s water meter.

(Ord. No. 88-8, § 1, 6-6-1988; Ord. No. 92-4, § 1, 4-6-1992)

(a) Approval of Backflow Preventers. Only backflow preventers that have passed both laboratory and field evaluations by a recognized testing agency and accepted by both the city and the health agency should be used.

(1) For water connections, where backflow prevention is required, other than fire systems, a reduced pressure device (RP) shall be the minimum protection allowed.

(b) Installation Requirements.

(1) Air-Gap Separation (AG). The air-gap separation should be located on the water user’s side of and as close to the user connection as is practicable. All piping from the user connection to the receiving tank shall be above grade and entirely visible unless the city and health agency approve the burial of the line. Water take-offs between the user connection and the air-gap separation shall be protected in a manner approved by the health agency and city.

(2) Reduced Pressure Principle Device (RP). The approved reduced pressure principle device should be installed on the user’s side of and as close to the user connection as is practicable. The device should be installed not less than twelve (12) inches above grade and shall be readily accessible for maintenance and testing. Water take-offs between the user connection and the RP should be protected in a manner approved by the health agency and city.

(3) Double-Check Valve (DC). The double-check valve should be located on the user’s side of and as close to the user connection as is practicable. The double-check valve should be preferably above grade and readily accessible for maintenance and testing. Water supplied from any point between the user connection and the DC should be protected in a manner approved by the health agency and city.

(4) Pressure Vacuum Breaker (PVB). The pressure vacuum breaker should be located such that the critical level (C-L) is: (a) At least twelve (12) inches above the highest point reached by any water beyond the device; and (b) not less than twelve (12) inches above the surrounding grade or floor. The PVB shall be readily accessible for maintenance and testing. The PVB shall not be subjected to back pressure. Only industrial (nonpotable) fluid may be supplied from beyond the PBV. (Refer to section 27.83 for definition of “critical level.”)

(5) Atmospheric (Nonpressure) Vacuum Breaker (AVB). The atmospheric (nonpressure) vacuum breaker should be located such that the critical level (C-L) is at least six (6) inches above the highest elevation of the piping system beyond the AVB. Fixtures with integral vacuum breakers manufactured and approved as a unit may be installed in accordance with their approval requirements. At no time should an AVB be subjected to back pressure.

(c) Backflow Protection Devices Required. Backflow prevention devices shall be required at the service connection, or at a location approved by the director of public works, for premises in the following described categories:

(1) Premises having an auxiliary water supply.

(2) Industrial/commercial premises on which any substance is handled under pressure in such a fashion as to permit possible entry into the city’s distribution system, including water originating from the city’s system which is boosted in pressure.

(3) Industrial/commercial or residential premises which, in the opinion of the director of public works, contain cross-connections or the potential for cross-connections which could result in the pollution or contamination of the city’s water system in the event of backflow.

(d) Fire Systems. A fire-fighting system with a direct connection to the public potable water system should be protected in a manner commensurate with the hazard. Fire protection systems may be classified as follows:

(1) Class I: Direct connections from domestic water mains only; no pumps or reservoir; no physical connection from other water suppliers; no antifreeze or other additives of any kind; and all sprinkler drains discharging to atmosphere, dry wells, or other safe outlets.

(2) Class II: Same as Class I, except that booster pumps may be installed in the connections from the street mains. (Booster pumps do not affect the potability of the water supply. It is necessary, however, to avoid drafting so much water that pressure in the water main is reduced below 10 psi.)

(3) Class III: Direct connection from public water supply main plus one or more of the following: Elevated storage tanks; fire pumps taking suction from above-ground covered reservoirs or tanks; or pressure tanks. All storage facilities are filled or connected to public water only; the water in the tanks to be maintained in a potable condition.

(4) Class IV: Directly supplied from public mains similar to Classes I and II, connection for fire pumper truck or with an auxiliary water supply on or available to the premises.

(5) Class V: Directly supplied from public mains and interconnected with auxiliary supplies, such as: pumps taking suction from reservoirs exposed to contamination or from rivers and ponds; driven wells; mills or other industrial water system; or system where antifreeze or other additives are used.

(6) Class VI: Combined industrial and fire protection systems supplied from the public water mains only, with or without gravity storage or pump suction tanks.

Class I and II fire protection systems will not require backflow protection at the service connection.

Class III systems should be provided with minimum protection (approved double-check valves) to prevent contaminated waters from backflowing in the public potable water system.

Class IV systems should be provided with a minimum of a DC at the service connection. An AG or RP may be required depending on the quality of the auxiliary supply.

Class V systems should be provided with maximum protection (AG or RP) to protect the public potable water system.

Class VI system protection depends on the requirements of both industry and fire protection and could only be determined by a survey of the premises.

A meter (compound, detector check) should not be permitted as part of a backflow protection device. An exception may be made, however, if the meter and backflow preventer are specifically designed and approved for that purpose.

(e) Use of Fire Hydrants. The city allows the use of water directly from fire hydrants for flushing storm and sanitary sewers and similar uses. When this is permitted, it is mandatory that a portable RP be provided by the user to protect the city water system.

(f) Additional Information. For additional detailed information not mentioned in this article, see “The Manual of Connection Control Procedures and Practices,” published by the State of California, Health and Welfare Agency, Department of Health Services.

(Ord. No. 88-8, § 1, 6-6-1988; Ord. No. 92-4, § 1, 4-6-1992; Ord. No. 92-8, § 1, 7-6-1992)

(a) At the time an application for a new water service is made by a potential customer, the director of public works will review such application to determine the need for a backflow prevention device on the customer’s service. If a backflow prevention device is determined to be required it shall be the customer’s responsibility at the customer’s expense to provide for installation of the device in accordance with the city standards and at a location approved by the city.

(b) A backflow prevention device installed by the customer must be of the type and manufacturer approved by the city. Devices installed by the customer shall be tested at the customer’s expense by a certified tester before the occupancy permit is released by the city.

(c) Installation of a backflow prevention device, where required by the city, shall be a condition of obtaining a water service and meter installation.

(Ord. No. 88-8, § 1, 6-6-1988)

(a) The city will inspect the premises of existing service connections which in the opinion of the director of public works may require backflow prevention. If it is determined that a backflow prevention device is required, the installation of a backflow prevention device shall be a condition of continued water service.

(b) If a customer fails to provide for the installation of the backflow prevention device within a reasonable time limit set forth in a written notification from the city, the city may suspend water service to the property being served.

(Ord. No. 88-8, § 1, 6-6-1988)

(a) An existing backflow prevention device which, in the opinion of the director of public works, is a type that does not provide adequate protection for the degree of potential hazard from backflow shall be upgraded at customer expense following the procedures in section 27.86 of this chapter.

(b) Upgrading may include complete replacement of the backflow prevention device, installation of additional devices, correction of on-site cross-connection hazards, or additional periodic testing.

(Ord. No. 88-8, § 1, 6-6-1988)

Backflow prevention devices installed or upgraded by the customer shall be and remain the property of the customer.

(Ord. No. 88-8, § 1, 6-6-1988)

The customer is responsible to provide for annual testing, or more often in those instances where successive inspections indicate repeated failure, of the backflow prevention device. Customers must advise the city in writing and must use a certified tester to inspect and test a backflow prevention device. The test shall be performed and results reported to the city within thirty (30) days of written notice by the city that testing is required.

City personnel and a designated private certified tester will inspect and test backflow prevention devices of those customers who refuse to hire a certified tester on their own. Charges for said inspection and testing shall be equal to the city’s cost including overhead and will be borne by the customer.

Devices which fail to pass inspection and testing by private certified testers shall be maintained and repaired in accordance with sections 27.90 and 27.91 of this chapter. The city reserves the right to require more frequent testing when the city determines it to be in the public interest. The customer shall bear the cost of additional tests if their device fails a test.

(Ord. No. 88-8, § 1, 6-6-1988; Ord. No. 92-4, § 1, 4-6-1992)

The customer shall be responsible for maintenance and repair of the backflow prevention device. The customer shall at all times maintain the device in proper working order as a condition of continued water service. If a backflow prevention device should fail to pass inspection and testing pursuant to section 27.89 of this chapter, the customer shall, within thirty (30) days after notification of test results, provide for repair of the device by the method set out in section 27.91.

(Ord. No. 88-8, § 1, 6-6-1988)

Repairs and satisfactory retest of backflow prevention devices by a certified tester shall be documented and submitted on a form approved by the city. Failure by the customer to repair a backflow prevention device within the time period allowed by the city may result in termination of water service.

(Ord. No. 88-8, § 1, 6-6-1988; Ord. No. 92-4, § 1, 4-6-1992)

As a condition of water service for new customers and as a condition of continued water service for existing customers, the customer may be required to have a backflow prevention device installed on the private property of the customer. The customer shall permit the city or other authorized personnel to enter upon the customer’s property within the normal working hours of the city, or in case of emergency, at any time, to test or inspect the backflow prevention device as set forth in other sections of this article.

(Ord. No. 88-8, § 1, 6-6-1988)

In addition to the rights granted the city in this article, the city may terminate water services to any premises served if a required backflow prevention device is removed by the customer or if the city finds evidence that an installed backflow prevention device has been bypassed, made or allowed to remain ineffective.

(Ord. No. 88-8, § 1, 6-6-1988)

Any person or persons, company, corporation or association who fails to install or who bypasses, alters or refuses to maintain a backflow prevention device, shall be guilty of an infraction. Unless otherwise stated: (1) A fine not exceeding one hundred dollars ($100.00) for a first violation; (2) a fine not exceeding two hundred dollars ($200.00) for a second violation of the same ordinance within one year; (3) a fine not exceeding five hundred dollars ($500.00) for each additional violation of the same ordinance within one year. For this purpose, a bail forfeiture shall be deemed to be a conviction of the offense charged. This section shall not be construed to limit the city’s remedies under any other law, including section 1.7 of the Gilroy City Code, for violations of its ordinances.

(Ord. No. 92-4, § 1, 4-6-1992)