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Portland Water Bureau

From forest to faucet, we deliver the best drinking water in the world.

GENERAL INFORMATION: 503-823-7404

1120 SW Fifth Ave, Suite 600, Portland, OR 97204

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Backflow Assemblies

Backflow prevention assemblies, devices, and/or methods are utilized on water supply piping to protect public water supplies from backflow hazards.


The assemblies protect against hazards caused by backpressure or back-siphonage conditions that could cause pollutants or contaminants to backflow into the public water supply and/or the water user's system.


Air Gap Backflow Prevention

Non-mechanical means of backflow prevention

Backflow Assembly Maintenance

Backflow assemblies are required by law to be tested at least once a year to make sure they are functioning properly.