Backflow testing & repair in Concord & the Bay Area.
Certified testing. Same-day repair. We file the report for you.
Annual backflow testing is required by your water district — and a failing assembly means you're out of compliance until it's fixed. We test, repair if needed, and submit the passing report directly to CCWD or EBMUD. One visit. Done.
- Certified backflow testers — USC FCCCHR certified — accepted by all Bay Area water districts.
- Repair on the same visit — We carry parts for RPZ, DCVA, and PVB assemblies.
- We file with the water district — Compliance report submitted for you — nothing left to do.
- CA Lic. #802256 — Licensed, insured, and family-owned since 2001.
USC FCCCHR Certified
Accepted by CCWD, EBMUD & all Bay Area water districts
What We Do
Testing, repair,
and full compliance.
Backflow prevention protects the public water supply from contamination — and most water districts require annual testing by a certified tester to prove your assembly is working. A failed test means a non-compliant property until it's repaired and retested.
We handle the full cycle: schedule the test, perform it on site, repair or replace any failing components, retest, and file the compliance report with your water district. You receive a copy for your records.
Schedule annual testingHow It Works
One visit.
Test, repair, report — done.
- Step 1:
Schedule & Confirm
We confirm your assembly type, water district, and any access requirements before arrival. No surprises on site.
- Step 2:
Test the Assembly
Certified tester performs a differential pressure test per USC FCCCHR and water district standards. Pass/fail recorded on-site.
- Step 3:
Repair If Needed
Failing assemblies are repaired on the same visit when possible. We carry seats, springs, diaphragms, and check kits for common makes.
- Step 4:
File the Report
We submit the test report to your water district directly. You receive a copy. Your compliance record is updated — no extra steps.
Compliance Guide
Repair, replace, or new install?
Not every failing assembly needs full replacement — and not every property owner knows what they're required to install in the first place. Here's how we think about it.
Repair vs. replace vs. new install
Worn seats, springs, or diaphragms. We rebuild on-site. Most repairs under one hour.
A corroded body can't be reliably rebuilt. Replacement is the compliant and cost-effective answer.
Any new irrigation system, fire line, boiler feed, or process water connection requires a code-approved assembly and permit.
Signs your assembly needs attention
- Failed or overdue annual test
- Visible corrosion on the body or fittings
- Leaking or dripping from the relief valve
- Water district violation notice received
- Assembly is 15+ years old
- Property recently added an irrigation system or fire line
FAQ
Common questions
Most water districts in Contra Costa County — including CCWD and EBMUD — require annual backflow preventer testing. Some high-hazard assemblies require testing more frequently. We'll confirm your specific schedule based on your water district and assembly type.
If your device fails, we repair or replace it on the same visit whenever possible. We carry common repair parts on the truck. After the repair, we retest the assembly and file the passing report with your water district — one call handles it all.
Yes. After every passing test, we submit the compliance documentation directly to your water district. You receive a copy for your records. This is included in our testing fee — no extra step required on your end.
We test and service all assembly types: Reduced Pressure Zone (RPZ), Double Check Valve Assembly (DCVA), Pressure Vacuum Breaker (PVB), Spill-Resistant PVB, and Atmospheric Vacuum Breakers. Residential, commercial, and industrial.
Yes. We install RPZ assemblies, DCVAs, and PVBs for new irrigation systems, fire suppression lines, boiler feed lines, and any other cross-connection point. We pull the permit, install to code, and coordinate the initial test.
A standard annual test takes 30–45 minutes per assembly. If repair is needed, add another 30–60 minutes depending on the issue. We schedule test-and-repair visits together so you're not waiting on a second appointment.
Yes. Restaurants, office parks, HOAs, apartment complexes, and industrial facilities are all common clients. If you manage multiple properties, ask about our annual service agreement — we track your test schedules and send reminders before due dates.
What Clients Say
Trusted by property managers
across the Bay Area.
“They test all four of our backflow assemblies every year and file everything with the water district. We don't have to think about it — they send us a reminder and handle the rest.”
“Our RPZ assembly failed the annual test. They had the parts on the truck, repaired it, retested, and filed the report the same morning. Zero disruption to the building.”
“Manage several commercial properties and have been using Guerra Bros. for all backflow compliance for three years. Professional, on time, and the paperwork is always clean.”
Where We Work
Backflow Testing & Repair near you.
Same-day service available in Concord, Walnut Creek, Martinez, and throughout Contra Costa County.
Don't see your city? Call us — we may still serve your area.
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