Milpitas Municipal Code Ch. 3 Backflow Prevention & Cross-Connection Control

The purpose of this Chapter is to protect the health of the water customers by the control of actual or potential cross-connections through two basic programs:

(a) Through proper installation and maintenance of backflow preventers on services to premises where actual or potential cross-connections exist to prevent backflow or back-siphonage of contaminants or pollutants from the customer's premises into the Public Water System.

(b) By promoting the elimination of existing or future cross-connections through inspection and regulation of plumbing and water piping within a customer's premises, Public Water System or between them.

1.01 Authority. Title 17, Chapter V, Sections 7583-7622, inclusive of the California Code of Regulations entitled "Regulations Relating to Cross-Connections," gives the City authority to protect the Public Water System from contamination and pollution.

The City Engineer on behalf of the City shall have authority to protect the Public Water System from contamination or pollution due to the backflow or back-siphonage of contaminants or pollutants through water service connections by implementation and enforcement of a backflow prevention and cross-connection control program based on accepted standards.

(Ord. 232 (part), 12/20/88)

For purposes of this Chapter, the terms used herein are defined as follows:

2.01 Auxiliary Water Supply. Any water supply available to the premises other than the Public Water System. These auxiliary supplies may include water from another purveyor's public potable water supply or any natural source such as a well, spring, river, stream, harbor, etc., or "used water" or "industrial fluids." These waters may be polluted or contaminated or they may be objectionable and constitute an unacceptable water source over which the City has no sanitary control.

2.02 Backflow. The undesirable flow of water or other liquids, gases or solid substances under pressure into the distributing pipes of the Public Water System from any outside source.

2.03 Back-Siphonage. The flow of water or other liquids, gases or solid substances into the distribution pipes of the Public Water System from any outside source caused by the sudden reduction of pressure in the Public Water System.

2.04 Backflow Prevention Device. A device or means designed to prevent backflow or back-siphonage. Types of backflow prevention devices are as follows:

2.04-1 Double Check Valve Assembly. An assembly of two independently operating approved check valves with tightly closing shutoff valves on each side 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 devices. To be approved, these devices must be readily accessible for in-line maintenance and testing and be installed per City standards.

2.04-2 Reduced Pressure Principle Backflow Prevention Device. An assembly of two independently operating approved check valves with an automatically operating differential relief valve between the two check valves, tightly closing shutoff 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. 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 System side of the device. At cessation of normal flow the pressure between the two check valves shall be less than the pressure on the Public Water System side of the device. In case of leakage of either of the check valves, the differential relief valve shall operate to maintain the reduced pressure in the zone between the check valves by discharging to the atmosphere. When the inlet pressure is two pounds per square inch or less, the relief valve shall open to the atmosphere. To be approved, these devices must be readily accessible for in-line maintenance and testing and be installed per City standards.

2.05 Contamination. Any 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.

2.06 Cross-Connection. Any physical connection or arrangement of piping or fixtures where backflow or back-siphonage might occur between any part of a water system, used or intended to supply water for drinking purposes, and water or any source or system containing substance that is not or cannot be approved as safe, wholesome, or potable for human consumption.

2.07 Hazard, Degree of. The term is derived from an evaluation of the potential risk to public health and the adverse effect of the hazard upon the Public Water System.

2.07-1 Hazard—Health. Any condition, device, or practice in the water system and its operation which, based on the Manual of Cross-Connection Control, could create a danger to the health and well-being of the water customers. An example of a health hazard is a structural defect, including cross-connections, in a water supply system.

2.07-2 Hazard—Plumbing. A plumbing type cross-connection in a customer's potable water system has not been properly protected by a backflow prevention device. Unprotected plumbing type cross-connections are considered to be a health hazard.

2.07-3 Hazard—Pollutional. An actual or potential threat to the physical properties of the Public Water System or to the potability of either the Public or the Customer's 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.

2.07-4 Hazard—System. An actual or potential threat of severe damages to the physical properties of the Public Water System or the Customer's Water System or of a pollution or contamination which would have a protracted effect on the quality of the water in the system.

2.08 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, plumbing, pollutional or system 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 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 water 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, etc.; oils, gases, glycerine, paraffins, caustic and acid solutions and other liquid and gaseous fluids used in industrial or other purposes or for fire-fighting purposes.

2.09 List of Approved Backflow Prevention Devices. The most recent list of approved backflow prevention assemblies from the University of Southern California, School of Engineering, Foundation for Cross-Connection Control and Hydraulic Research.

2.10 Manual of Cross-Connection Control. The latest edition of the Manual of Cross-Connection Control as published by the Foundation for Cross-Connection Control and Hydraulic Research, University of Southern California, University Park, Los Angeles, CA 90089.

2.11 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.

2.12 Service Connection. The terminal end of the Public Water System; i.e., where the City of Milpitas 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 customer's meter. There should be no unprotected takeoffs from the service line on the City's side of the meter or backflow prevention device located at the point of delivery to the Customer's Water System. Service connection shall also include water service connection from a fire hydrant and all other temporary or emergency water service connections from the Public Water System.

2.13 Used Water. Any water supplied by the City from the Public Water System to a Customer's Water System after it has passed through the service connection and is no longer under the sanitary control of the City.

2.14 Water System. The water system shall be considered as made up of two parts: The Public Water System and the Customer's Water System.

2.14-1 The Public Water 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 up to the point where the Customer's Water System begins the service connection.

2.14-2 The Source shall include all components of the facilities utilized in the production, treatment, storage, and delivery of water to the distribution system.

2.14-3 The Distribution System shall include the network of conduits used for the delivery of water from the source to the Customer's Water System.

2.14-4 The Customer's Water System shall include those parts of the facilities beyond the service connection of the Public Water System for distributing water.

(Ord. 232 (part), 12/20/88)

3.01 Water Service. No water service connection to any premises shall be installed or maintained by the City unless the water supply is protected from contamination and pollution. Service of water to any premises shall be discontinued by the City if a backflow prevention device required by this Chapter is not installed, tested and maintained, or if it is found that a backflow prevention device has been removed, by-passed, or if any unprotected cross-connection exists on the premises. Service will not be restored until such conditions or defects are corrected to the satisfaction of the City Engineer.

3.02 Open for Inspection. The Customer's Water System shall be open for inspection at all times to authorized representatives of the City Engineer to determine whether cross-connections, hazards (health, plumbing, pollutional, system), or violations of this Chapter exist. When an imminent hazard to public health or safety becomes known, the City Engineer may deny or immediately discontinue water service to the premises until the customer has corrected the condition to the satisfaction of the City Engineer.

3.03 Approval of Devices. Any backflow prevention device required herein shall be of a model and size as shown on the list of approved backflow prevention devices.

Backflow preventers which may be subjected to back-pressure or back-siphonage that have been fully tested and have been granted a Certificate of Approval by a certified laboratory and is listed on the City's current list of "Approved Backflow Prevention Devices" may be used without further test or qualification.

3.04 Existing Users—with a non-complying device. All presently installed backflow prevention devices which do not meet the requirements of this section, but were approved devices for the purposes described herein at the time of installation and which have been properly maintained, shall be excluded from the requirements of these rules so long as the City Engineer is assured that they will satisfactorily protect the Public Water System based on the testing and maintenance requirements described in Section 7.00. Whenever the existing device is moved from the present location or requires major repair, the unit shall be replaced by a backflow prevention device meeting the requirements of this Section.

3.05 Evaluation of Hazard. An evaluation of cross-connection hazards shall be performed when, as specified in the Manual of Cross-Connection Control, an existing user might pose an actual or potential cross-connection hazard.

3.06 Existing Users—without any device. All customers and premises existing prior to adoption of this Chapter are subject to an evaluation of hazard by the City Engineer in accordance with the Manual of Cross-Connection Control to determine if backflow devices shall be required. If it is determined that an existing premises requires backflow prevention under Section 4.00, then the City Engineer shall give notice in writing to the customer to install an approved backflow prevention device within 180 calendar days or the City shall discontinue water service. Certification of the device installed shall be executed within ninety days from date of notice.

(Ord. 232 (part), 12/20/88)

4.01 An approved backflow prevention device shall be installed per standard drawings adopted by the City and the list of approved backflow prevention devices. The device shall be installed prior to the issuance of a final occupancy permit on each service line to a Customer's Water System at or near the property line and before the first branch line leading off the service line. This shall apply to certain commercial and industrial businesses, separate irrigation systems, and hillside residences (without Polyvinyl Chloride Pipe (PVC) fire service) and wherever the following conditions exist:

4.01-1 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 potable source as determined by the Manual of Cross-Connection Control, 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.

4.01-2 In case of the premises which any industrial fluid or any other objectionable substance is handled in a manner that could permit the fluid or substance to enter the water system, 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. This shall include the handling of process waters and waters originating from the Public Water System which have been subject to deterioration in quality.

4.01-3 In the case of premises having internal cross-connection that cannot be permanently corrected, 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.

4.01-4 In the case of premises having intricate piping arrangements or where entry to all portions of the premises is restricted so that inspections for cross-connections cannot be made with sufficient frequency or at sufficiently short notice to assure that no 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 appropriate to the degree of hazard.

4.01-5 In the case of premises having a repeated history of cross-connections being established, or re-established, the Public Water System shall be protected against backflow from the premises, appropriate to the degree of hazard, by installing a backflow prevention device in the service line.

(Ord. 232 (part), 12/20/88)

5.01 The backflow prevention device required under Section 4.00 is as follows:

5.01-1 A double check valve assembly on all irrigation systems.

5.01-2 A reduced pressure principle backflow prevention device on certain commercial or industrial domestic systems.

5.01-3 A double check valve assembly on all Hillside residences where PVC pipe is not used.

5.02 An evaluation of hazard will be performed by the City Engineer or his staff based on the Manual of Cross-Connection Control to determine the degree of hazard and what, if any, backflow prevention device shall be required. The following guidelines shall be used in evaluating each customer activity.

5.02-1 In the case of a customer activity where toxic or hazardous substances are handled in any manner which may allow for contamination for the water system, the Public Water System shall be protected by a reduced pressure principle backflow prevention device at the service connection.

5.02-2 In the case of a customer activity where there is 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 at the service connection.

5.02-3 In the case of a customer activity where an unapproved auxiliary water supply is interconnected with the water system, the Public Water System shall be protected by an approved reduced pressure principle backflow prevention device at the service connection.

5.02-4 In the case of a customer activity where an unapproved auxiliary water supply exists and there is no interconnection, the Public Water System shall be protected by a double-check valve assembly at the service connection.

5.02-5 In the case of a customer activity where there are internal cross-connections that cannot be permanently corrected, either actual or potential, the Public Water System shall be protected by an approved reduced pressure principle backflow prevention device at the service connection.

5.02-6 In the case of a customer activity having intricate piping arrangements or entry to all portions of the premises is restricted so that inspections for cross-connections cannot be made with sufficient frequency at sufficient short notice to assure no cross-connections exist, the Public Water System shall be protected against backflow or back-siphonage from the premises by the installation of a reduced pressure principle backflow prevention device at the service connection. In this case, maximum protection will be required; that is, an approved reduced pressure principle backflow prevention device shall be installed in each service to the premises.

5.02-7 In case of a customer activity on which a non-residential irrigation system exists where fertilizer, herbicides, or pesticides can be injected into the irrigation system, the Public Water System shall be protected against backflow or back-siphonage from the premises by the installation of a reduced pressure principle backflow prevention device at the service connection.

5.02-8 In the case of a customer activity where a fire system exists and there is direct connection from the Public Water System to elevated storage tanks or fire pumps taking suction from private reservoirs, the Public Water System shall be protected against backflow or back-siphonage from the premises by the installation of a double check valve assembly at the service connection.

5.02-9 In the case of a customer activity where a fire system exists and is 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 systems; or systems where anti-freeze or other additives are used) the Public Water System shall be protected against backflow or back-siphonage from the premises by the installation of a reduced pressure principle backflow prevention device at the service connection.

5.02-10 In the case of a customer activity where a fire system exists and this system is supplied from the public water supply and is treated with chemical retardants for the purpose of controlling fires, the Public Water System shall be protected against backflow or back-siphonage from the premises by the installation of a reduced pressure principle backflow prevention device at the service connection.

5.03 When a Double Check Valve Assembly is cited as the required device for that customer activity in this section, a reduced pressure principle backflow prevention device may be used if the customer prefer. The requirement for a double check valve is a minimum requirement and the maximum protection can be used.

(Ord. 232 (part), 12/20/88)

6.01 Installation of backflow preventers required by this section shall be as follows:

6.01-1 The backflow protection device shall be installed by the customer on the customer water service side within six inches (6″) of property line per City standards.

6.01-2 All backflow preventers shall be readily accessible for testing and repair.

6.01-2(1) Reduced Pressure Principle Backflow Prevention Device. Reduced Pressure Principle Backflow Prevention Devices shall be installed a minimum of twelve inches (12″) above grade and not more than thirty inches (30″) above grade measured from the bottom of the device. There shall also be a minimum twelve inches (12″) side clearance.

6.01-2(2) Double Check Valve Assembly. Double Check Valve Assembly shall be installed a minimum of twelve inches (12″) above grade and not more than thirty inches (30″) above grade measured from the bottom of the device. There shall also be a minimum twelve inches (12″) side clearance.

(Ord. 232 (part), 12/20/88)

7.01 It shall be the responsibility of the City at any premises where a backflow prevention device is installed to have proper certified inspection and operational testing. Testing of the device shall be at initial installation and once per year henceforth by the City. In those instances where the City Engineer deems the hazard to be great enough, he may require certified inspections and testing at more frequent intervals.

7.02 The inspections and tests shall be performed by City of Milpitas personnel or by a certified tester approved by the City. The City Engineer shall establish a list of certified testers. These tests shall be at the expense of the customer.

7.03 Any defective device shall be immediately repaired, overhauled or replaced by and at the expense of the customer whenever said devices are found by the City to be defective. Then the modified device, or replacement device, shall be retested by the City.

7.04 Records of all repairs and overhauls shall be filed with the City Engineer within sixty (60) days of notification date on the City's Test and Maintenance Report.

(Ord. 232 (part), 12/20/88)

Except as otherwise provided by this Chapter and where a hearing on the matter is not otherwise required to be had by the City Council, any person aggrieved by decision of any officer or department of City may appeal to the City Council in accordance with provisions of Section 5, Chapter 20, Title I of Milpitas Municipal Code.

(Ord. 232 (part), 12/20/88)

The City may discontinue water service to any premises served if a required backflow prevention device is removed, or if the City finds evidence that an installed backflow prevention device has been by-passed, or allowed to remain ineffective.

Any person or persons, company, corporation or association, who shall violate any of the provisions of this Chapter or fail to comply therewith, or who shall violate or fail to comply with any order made thereunder, shall severally for each and every violation and non-compliance respectively, be guilty of an infraction, punishable in accordance with the provisions of I-1-4.09-1 of the Milpitas Municipal Code. The imposition of one fine for any violation shall not excuse the violation or permit it to continue; and all such persons shall be required to correct or remedy such violations or defects within a reasonable time; and when not otherwise specified, each day that prohibited conditions are maintained shall constitute a separate offense.

The application of the above fine shall not be held to prevent the enforced removal of prohibited conditions.

The requirements and procedures for Backflow Prevention and Cross-Connection Control as established by Ordinance 232 shall become effective starting January 20, 1989.

(Ord. 232 (part), 12/20/88)