Frequently Asked Questions (FAQ's)
Q: What is backflow?
A: The reverse flow of the water supply.
Q: What causes backflow?
A: Backflow is possible in two situations, backsiphonage and back pressure.
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.
Q: What is back pressure?
A: Back pressure is created when pressure in a non-potable system, such as in a recirculating system containing soap, acid, or antifreeze, exceeds that in the potable system that provides make up water to the system. This can force the potable water to reverse its direction of flow through the cross connection.
Q: What is backflow prevention?
A: It is the prevention of water from flowing in reverse.
There are four methods of backflow prevention:
- Air Gap
- Double Check Valve Assembly
- Reduced Pressure Principal Assembly
- Pressure Vacuum Breaker Assembly
Q: What is a backflow assembly?
A: A backflow preventer is an approved, testable assembly which uses valves, in different configurations, to prevent polluted or contaminated water from reversing direction and flowing backward.
Q: Who is required to have a backflow prevention 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. Although this does not include your lawn irrigation system because it can contaminate your household water.
However, residences used for other purposes such as medical, dental offices and dental labs, as well as commercial and industrial customers such as auto repair/car washes/funeral homes/surgery centers/hospitals, may be required to install and maintain backflow prevention assemblies.
When a determination is made by health official that the potable water system may be subject to contamination through backflow, a backflow prevention assembly will be required.
Q: Who should install a backflow prevention assembly?
A: The installation of the backflow prevention assembly should only be done by a licensed professional.
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 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
Q: Why does it need to be tested?
A: Annual testing is required to stay in compliance. It needs to be tested annually to ensure that it is working properly and not allowing contaminants to flow back into the main water supply. If any repair work or maintenance is performed on the assembly, a recognized Tester must retest the assembly immediately and submit the test results to the Backflow Prevention Section.
