Irrigation Wells Program

Press Enter to show all options, press Tab go to next option

If you have a well on your residential OR commercial property, whether it is in use or not, follow the steps below to ensure that your well and backflow assembly are in compliance with Redwood City's Cross Connection Control Ordinance and the California State Water Resources Control Board - Division of Drinking Water Title 17 requirements.

Step 1 - Apply For A Well Permit

Fill out a free well permit and return it to Public Works, 1400 Broadway, or email it to

Step 2 - Determine Backflow Status

Upon receipt of the well permit, Public Works will inspect the well to evaluate:

  1. If a backflow assembly needs to be installed
  2. What type of backflow assembly to install, if needed

Reference the chart below to see how the team will determine the necessary backflow assembly. This inspection is free of charge.

Required Assembly
  • Your well is operational.
  • Your irrigation system uses well or creek water AND City drinking water.
  • The two systems are easily interconnected.

A Reduced Pressure Principle Backflow Prevention Assembly (RP) must be installed at the water meter above ground.


  • Your well is operational.
  • Your sprinkler system uses ONLY well or creek water.
  • The two systems are NOT tied together, and you are NOT able to switch to City water.

A Double Check Valve Backflow Prevention Assembly (DC) may be installed at your water meter below ground in a vault.


  • Your on site well is NOT operational.
  • Your well no longer
    has plumbing attached to it.

Instead of a backflow assembly at the meter, the City will perform annual inspections to verify non-use.

Step 2b - Install a Backflow Assembly

If the well on your property requires a backflow device (RP or DC), then you must apply for a backflow permit from City Hall (1017 Middlefield). If your well is not operational, you do not need a backflow permit.

After obtaining a backflow permit, install the proper backflow device by yourself or with a professional. 

Once your backflow device has been installed, contact Public Works to perform a post-inspection on the device to ensure that it is properly installed. This inspection is free.


Step 3 - Annual Testing or Inspection

Operational Well (with backflow assembly)

  1. Every year, you will receive a notice in the mail stating when your backflow test is due. 
  2. An annual test must be performed on the backflow device. Your backflow prevention assembly must be tested by one of the qualified backflow assembly testers on the Backflow Prevention Assembly Tester List. Alternatively, you may request a test through Public Works.
  3. Backflow Assembly Testers must submit a completed Backflow Prevention Assembly Field Testing and Maintenance Report to Public Works (1400 Broadway) within thirty days following the testing due date. Backflow testers should visit the Backflow Testers page for details on this inspection.
  4. The City imposes an annual Test Result/Record filing fee for properties with backflow devices. There is an additional testing fee if Public Works is requested to test the device. Click here for a summary of fees.

Non-Operational Well (no backflow assembly)

Instead of an annual test, non-operational wells require a non-operational well inspection. Every year, you will receive a notice stating when your well inspection is due. 

This inspection is done through Public Works and has a fee. Click here for a summary of fees.

If you would like more information or have any questions, please contact the City's Water Resource Management program staff at (650) 780-7464.


If you have questions about any cross connection control program fees, please visit the Fees page.