Backflow Prevention

Backflow is the undesirable reversal of the flow of water or mixtures of water and other undesirable substances from any source (such as used water, industrial fluids, gasses, or any substance other than the intended potable water) into the distribution pipes of the potable water system. 

Cross Connection Control Program

A home owner or business owner is responsible if their water system contaminates the public water system. Your participation in the program is critical in assisting us to continue to deliver safe, reliable drinking water.

The City of Redmond, (Redmond-Municipal-Code-1310) in conjunction with the Washington State Department of Health (WAC 246-290-490) , requires customers within the Redmond water jurisdiction, that have the potential to back-flow water into the public system to install and maintain backflow assemblies. The most common concerns for residential customers are lawn irrigation and fire suppression systems.

A cross connection is an actual or potential pathway between our drinking water supply and a source of contamination or pollution. In our homes and businesses, water is often used to dilute, mix, cool and clean. Potable water may come in contact with dangerous chemicals and substances. Cross connected plumbing may put your drinking water in contact with contaminated water.  

The City of Redmond surveys commercial and residential properties to ensure cross connection compliance and safe drinking water quality. The need for cross connection control exists in all types of premises, whether industrial or residential.

Annual Testing

The City mails out reminder letters annually to all businesses and homeowners that need to have their assemblies tested. This is a simple testing procedure and mandatory for all water users that own a backflow assembly. The test is performed by any State Certified Backflow Assembly Tester, a list of local testers is included in the City’s reminder letter.

You can ensure your tester is certified by visiting Washington Certification Services BAT site where you can search by name or certification number.

If you have an irrigation system, fire system or any other potential cross connection and you don’t receive an annual letter from the City to test, please give us a call. We are pleased to help if you think you may need a backflow assembly or need information on how to get yours tested.