Backflow Frequently Asked Questions

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Q.  What is backflow?
A:  The Town of Queen Creek's water distribution system is designed to keep the water flowing to the customer. However, when hydraulic conditions within the water system deviates from the normal conditions, water flow can be reversed. When this backflow happens, contaminated water can enter the distribution system.

Q.  What causes backflow?
A:  Backflow is possible in two situations, backsiphonage and backpressure.

Q.  What is backsiphonage?
A:  When there is a sudden reduction in the water pressure in the distribution system, such as during firefighting or when a water main breaks, water flow can be reversed. This can create a suction effect, drawing the non-potable substances into the potable water system.

Q.  What is back pressure?
A:  Back pressure is created when pressure in a non-potable system, such as in a re-circulating system containing soap, acid, or antifreeze, exceeds that in the potable water system that is supplying water to the equipment. This can force the potable water to reverse its direction of flow through the cross connection. Non-potable substances can then enter the potable water system.

Q. How can backflow be prevented?
A:  By installing backflow prevention assemblies or devices in areas that are rated by degree of hazard or contamination. One of the following methods may be used:
        *  Air Gap
        *  Atmospheric Vacuum Breakers
        *  Pressure Vacuum Breaker Assembly
        *  Double Check Valve Assembly
        *  Reduced Pressure Principle Backflow Preventer

Q.  What is a backflow assembly?
A:  A backflow prevention assembly is an approved, testable assembly which uses valves, in different configurations, to prevent polluted or contaminated water from reversing direction and flowing backward.

Q.  How is an assembly approved?
A:  An approved backflow prevention assembly has gone through an approval process at the Foundation for Hydraulic Research and Cross Connection Control at the University of Southern California. This is a two-step process consisting of laboratory tests and a twelve-month field test. Only assemblies completing the entire testing procedure are recognized by the Town as approved backflow prevention assemblies.

Q.  Who is required to have a backflow assembly?
A:  Federal and State law require that water suppliers protect their water systems from contamination. State regulations exempt single family residences used solely for residential purposes from assembly requirements. However, residences used for other purposes, as well as commercial and industrial customers, are required by State Administrative Code rule R18-4-115 to install and maintain backflow prevention assemblies.

Q.  How do I know if I need a backflow assembly?
A:  Existing commercial, industrial or residential properties not used solely for residential purposes may have a Town of Queen Creek Backflow Prevention Inspector visit their property to do an evaluation for backflow requirements. Backflow requirements for new structures will be made by town staff during engineering reviews.

Q.  Who is responsible for the testing and maintenance of the backflow assembly?
A:  It is the sole responsibility of the customer to ensure that the assembly is in satisfactory operating condition at all times. The Town will send notices to customers advising them when an annual test is required on their backflow assembly. The customer must contact a Backflow Assembly Tester, recognized by the Town, to perform the test. If any repair work or maintenance is performed on the assembly, a recognized tester must retest the assembly immediately and submit the test report to the Backflow Prevention Inspector. Under normal conditions, backflow assemblies need to be tested on an annual basis. In high hazard conditions, multiple tests may be required each year.

Q.  Where should a backflow prevention assembly be located?
A:  Generally, the backflow prevention assembly must be located as close as possible to the water service connection, but must remain on private property.

Q.  Who can install a backflow prevention assembly?
A:  The installation of the backflow prevention assembly is the responsibility of the customer. The assembly may be installed by a property owner, plumbing contractor, or a general contractor, subject to the Rules and Statutes of the Arizona Registrar of Contractors. Be aware that a newly installed, repaired or replaced backflow assembly must be tested by a Town-approved certified backflow tester and results submitted to the Town of Queen Creek's backflow prevention inspector.

Q.  How do I find a certified tester?

A:  The Town of Queen Creek has contracted with Backflow Solutions, Inc (BSI) to administer their cross-connection control / backflow tracking program. The Town will be utilizing BSI Online for all test report submittals.

Q.  How do I find a certified tester?
A:  For a list of backflow specialists in our area contact BSIat 1-800-414-4990 or visit them online at bsionline@backflow.com  Test prices vary among testers. You may want to contact several certified testers to obtain quotes for your test. You may use another source for backflow inspection that is not on the list, however they would have to submit their Backflow Certifications to BSI Prior to them testing your unit.