13.04.170 Cross-connection control – Policy.
A. 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 regulations and this code. Service of water to any premises shall be discontinued by the water purveyor if a backflow prevention assembly required by this code is not installed, tested and maintained, or if it is found that a 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 customer’s system should be open for inspection at all reasonable times to authorized representatives of the city of Wasilla water utility to determine whether cross-connections or other structural or sanitary hazards or violations of this code exist. Water service may be discontinued after reasonable notice to the consumer if a violation of this code exists on the premises, and such other precautionary measures may be taken as are deemed necessary to eliminate any danger to the potable water. Water service shall not be restored until the danger has been eliminated in compliance with the provisions of this code.
C. An approved backflow prevention assembly shall be installed on each service line to a customer’s water system at or near the property line or immediately inside the building being served; but in all cases, before the first branch line 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 as determined by the director of public works, the public water system shall be protected against backflow from the premises by installing a backflow prevention assembly in the service line appropriate to the degree of hazard.
2. In the case of premises on which any industrial fluids 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 assembly in the service line appropriate to the degree of hazard. This shall include the handling of process waters and waters originating from the utility system which have been subject to deterioration in quality.
3. In the case of premises having internal cross-connections 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 assembly in the service line.
D. The type of protection assembly required by this code shall depend upon the degree of hazard which exists as follows:
1. In the case of any premises where there is an auxiliary water supply and it is not subject to any of the following rules, the public water system shall be protected by an approved air gap separation 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 into the public water system, the public water system shall be protected by an approved double check valve assembly.
3. 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 assembly. Example 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 problems 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 assembly at the service connection.
5. In 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 public water system shall be protected against backflow by backpressure or backsiphonage from the premises by using a 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 assembly shall be installed in each service to the premises.
E. Any backflow prevention assembly required herein shall be of a model and size approved by the director of public works. An approved backflow prevention assembly shall be manufactured in full conformance with the standards established by the American Water Works Association entitled: AWWA C510-97 – Double Check Valve Backflow Prevention Assembly; and AWWA C511-97 – Reduced Pressure Principle and Double Check Valve Backflow Prevention Assembly as well as the standards set forth by the Foundation for Cross-Connection Control and Hydraulic Research of the University of Southern California.
F. Customer Testing and Reporting Requirements.
1. It shall be the duty of the customer at any premises where backflow prevention assemblies are installed to have certified inspections and operational tests made at least once per year.
2. In those instances where the director of public works deems the hazard to be great enough, the director may require certified inspections at more frequent intervals.
3. These inspections and tests shall be performed by the assembly manufacturer’s representative, or by a certified tester approved by the director.
4. The customer shall notify the director in advance when the tests are to be undertaken so that their representative may witness the tests if so desired.
5. These assemblies shall be repaired, overhauled, or replaced at the expense of the customer whenever said assemblies are found to be defective.
6. Records of such tests, repairs, and overhauls shall be kept by the customer-user and copies provided to the city per the director’s instruction.
G. The city council may adopt charges and fees to recover costs for the city’s inspection and reporting requirements associated with its cross-connection policy and backflow prevention enforcement obligations.
H. All presently installed backflow prevention assemblies which do not meet the requirements of this section but were approved assemblies for the purposes described herein at the time of installation and which have been properly maintained shall, except for the inspection and maintenance requirements under subsection (F) of this section, be excluded from the requirements of these rules so long as the director of public works is assured that they will satisfactorily protect the utility system. Whenever the existing assembly is moved from the present location or requires more than minimum maintenance or when the director finds that the maintenance constitutes a hazard to health, the unit shall be replaced by a backflow prevention assembly meeting the requirements of this section.
I. Nothing herein shall relieve the customer of the responsibility for conducting, or causing to be conducted, periodic surveys of water use practices on their premises to determine where there are actual or potential cross-connections in the customer’s water system through which contaminants or pollutants could flow back into a public water system or potable consumer’s water system. (Ord. 24-05 § 2, 2024; Ord. 09-31 § 5, 2009)