Cross-Connection & Backflow Control Program

To keep your drinking water safe, the City’s Cross-Connection specialist diligently checks the plans of each new business for compliance with cross-connection/backflow requirements. When a property is renovated, a backflow assembly may be required. Per the City’s Municipal Code, each unit must be tested annually at the expense of the owner. In 2020, the City implemented a unified due date for testing. First notification letters are sent to all facilities/device owners annually in January, with a May 1st test submission deadline. 

What is a Cross-Connection?

A cross-connection is any connection between your drinking water and any other source of water that combines the two when a backflow condition occurs, typically resulting in contamination of the water system.

What is a Backflow?

Backflow occurs when the water in your pipes (after the water meter in your building/facility) goes backward (opposite its normal direction). There are two situations that can cause the water to go backward (backflow):

  • Backpressure: When the pressure in your pipes is greater than the pressure coming in.
  • Back-siphonage: When there is a reduction of pressure in the water distribution system.

All backflow prevention assemblies are to be tested annually at the owner’s expense (Ceres Municipal Code 13.28 and California Health and Safety Code 116800-116820). For a list of certified backflow testers, download or view our Current Certified Tester List

If you are a tester and would like to be added to our Certified Tester List, please submit a copy of the following information by email to

  1. Current City of Ceres Business License
    1. Please contact Muniservices for your business license status (866) 240-3665 or email
  2. Current AWWA Certificate and Card
  3. Current Backflow Test Kit Calibration Certificate