Backflow - Cross Connection

Effective March 15, 2022, the City of Rohnert Park will no longer accept test reports, please submit to BSI Online (

There is no fee to register with BSI Online, but you must submit copies of your credentials and test gauge calibration.

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What is Backflow?

Backflow is the undesirable reversal of flow of water or mixtures of water and other liquids into the public drinking water system. It is the City of Rohnert Park’s responsibility to protect the public drinking water supply from contamination that might occur through unintentional backflow.

Backflow events can result from backsiphonage or backpressure. If a backflow condition occurs or exists it is possible that the water supply could become contaminated through “cross connections”.

What is a backflow prevention assembly?

Backflow prevention assBackflow Prevention Assemblyemblies prevent the undesirable reversal of water flow into the drinking water system, ensuring a safe water supply. Backflow prevention devices are required on fire services and some domestic services to protect the public water supply from actual or potential contamination from cross connection and backflow. City of Rohnert Park’s Cross Connection Control Program is designed to meet the requirements of the California Code of Regulations, Title 17, and Public Health Sections 7583 through 7605.

Rohnert Park’s Cross Connection Control Program includes routine surveying of existing and new properties to determine the degree of hazard that may exist on a property.  The degree of hazard will determine the type and location of a required backflow prevention assembly.

Backflow prevention assemblies require annual testing and inspection. The cost shall be the sole responsibility of the customer. Notices will be sent by the City annually to facilities with backflow devices notifying them testing is due.  The City’s licensed Cross Connection Specialist ensures these required tests and inspections are completed. A certified tester from the City of Rohnert Park’s approved testers list must utilized to test your device.