Backflow Prevention & Testing Protect the Water Supply - Stay Compliant
Certified testing, repair, and installation of backflow preventers for Peninsula homes, businesses, and irrigation systems
What Backflow Is and Why Water Providers Require Prevention
Your water system is designed for flow in one direction: from the public main into your property. Backflow is that flow reversing - a pressure drop in the main (a water main break, a hydrant opened for firefighting) can siphon water backward from private plumbing into the public supply. If that backward-flowing water has been sitting in an irrigation system with fertilizer, a commercial boiler, or any connection to contaminants, it pollutes the drinking water for everyone downstream. Backflow preventers are the mechanical check that makes this impossible, and water providers take them seriously enough to mandate them.
That is why properties with irrigation systems, fire sprinkler services, commercial equipment, multi-unit buildings, and certain other configurations are required to have backflow prevention assemblies - and most Peninsula water providers require those assemblies to be tested annually by a certified tester, with results filed. Requirements vary by water district and connection type, so we confirm exactly what applies to your property as part of the service rather than guessing.
Testing, Repair, and Installation - Start to Finish
Annual testing is quick when the device is healthy: we test the assembly with calibrated gauge equipment, complete the certification, and file the report with your water provider so the compliance notice cycle stays quiet. When a device fails its test - worn check discs, fouled seats, a relief valve that will not hold - we repair it on the spot in most cases, retest, and file the passing result. Failed devices left unaddressed eventually escalate to water service consequences from the provider, so same-visit repair matters.
We also install new assemblies: for new irrigation systems, commercial tenant improvements, and properties that receive a notice requiring one. Installation includes selecting the correct assembly type for the hazard level, proper elevation and clearance for testability, and the initial certification test. If you have received a letter from your water provider about backflow requirements and are not sure what it means, send it to us - translating those notices into a fixed scope of work is something we do weekly.
Backflow Prevention FAQs
Do I really need my backflow preventer tested every year?
If your water provider requires it for your connection type - and most Peninsula providers do for irrigation, commercial, fire, and multi-unit connections - then yes, annually by a certified tester, with results filed. It is not bureaucratic theater: these are mechanical devices with rubber parts that wear, and the annual test is how failures get caught before a pressure event puts contaminated water into the public main.
What happens if my backflow device fails the test?
Usually nothing dramatic - most failures are worn internal parts we can rebuild during the same visit with a repair kit, then retest and certify. The thing to avoid is ignoring a failed test or a provider notice: unresolved backflow compliance eventually escalates to formal warnings and, ultimately, water service action. Same-visit repair keeps it a maintenance item instead of a problem.
I got a letter from the water district about backflow. What do I do?
Send it to us. Those notices typically mean one of three things: your annual test is due, your device failed or is missing required certification, or your property has been identified as needing an assembly installed. We confirm the actual requirement with the provider, do the testing, repair, or installation, and file the paperwork that closes the notice.
Does a home irrigation system need backflow prevention?
In general, yes - irrigation is one of the classic backflow hazards (sprinkler heads sit in soil with fertilizers and pet waste), and connections to it are required to be protected. The specific assembly type and testing requirement depend on your water provider and how the system connects. If your irrigation was installed without one, that is worth correcting before it becomes a compliance notice.
How much does backflow testing cost?
Testing is one of the more affordable line items in plumbing - a healthy device tests and certifies quickly. Repairs depend on the assembly size and parts, and new installations on the assembly type and pipe size. We quote before work begins, and for businesses with multiple devices we offer scheduled annual programs so compliance happens automatically.
Backflow Test Due? Get It Handled
Call (650) 269-0190 for Upfront Pricing
Testing, repairs, new installations, and the paperwork filed with your water provider. Licensed, bonded, and insured since 2010. CSLB #947961.
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