Do You Need Annual Backflow Testing in California? Yes — Here's Why

A backflow preventer is the device that keeps non-potable water from siphoning back into the public drinking water supply. California's Health and Safety Code and Title 17 require annual testing of every assembly protecting a hazardous connection — and on the Central Coast that includes a much wider list of properties than most owners realize.

Who actually needs it: every commercial property with an irrigation system, fire line, or boiler; every multifamily property with shared water service; restaurants with carbonators or grease interceptors; medical and dental offices; auto shops; and most residential properties with a dedicated irrigation meter. The local water purveyor (City of Grover Beach, City of San Luis Obispo, Golden State Water, etc.) sends an annual reminder, and they have the authority to shut off service if the test isn't filed.

What the test involves: a certified backflow tester (AWWA or USC-FCCCHR credentialed) connects calibrated gauges to the assembly, runs a sequence of checks on each valve, and submits a signed report directly to the water purveyor. The test itself takes 20–30 minutes per assembly. If the assembly fails, common repairs are a rebuild kit (new rubber seats and check assemblies) or, on older units, full replacement.

What it costs and how we handle it: a single-assembly test on the Central Coast is typically $95–$165, with rebuild kits in the $250–$500 range. We test, repair, and replace Zurn, Watts, Febco, and Wilkins assemblies across San Luis Obispo and Santa Barbara Counties, file the paperwork with the water purveyor for you, and put your property on an annual reminder so it never lapses. If you got a notice and aren't sure where to start, call us — we'll pull your address from the purveyor records and quote it in one call.