Backflow Testing & Prevention in Costa Mesa, CA
Backflow testing checks that the assembly protecting the public water supply still stops water from flowing backward out of your property. In Costa Mesa, CA, Mesa Water requires backflow assemblies to be tested every year, and a failed or missed test can put the water service at risk.
Why the test is required
Backflow happens when pressure drops in the public main, from a main break or heavy hydrant use, and water from a building siphons back into the street pipe. Irrigation water with fertilizer, a boiler or a restaurant's chemical lines are the kind of sources the assembly is there to stop.
Mesa Water states that federal Safe Drinking Water Act amendments, the California Code of Regulations and its own rules require annual testing. Protection inside the building also follows the California Plumbing Code, which is based on the Uniform Plumbing Code (UPC).
Which assembly do you have?
The type decides how the test is done and what can fail.
| Assembly | Where you see it | What it protects against |
|---|---|---|
| Reduced pressure principle (RP) | Commercial services, high-hazard uses. | Highest-risk cross connections. |
| Double check valve | Fire lines and lower-hazard services. | Lower-hazard backflow. |
| Pressure vacuum breaker (PVB) | Residential and commercial irrigation. | Back-siphonage from sprinklers. |
What happens on test day
- Notify. We let you know the water will be off briefly during the test.
- Test. A calibrated gauge checks each valve and relief point against its standard.
- Repair if needed. Failed assemblies are rebuilt or replaced, then retested.
- Report. Results are filed with your utility or given to you to submit.
Most tests take under an hour per assembly. Water is off only for a few minutes.
When to call before the test date
- Water discharging from the relief port on an RP assembly.
- A cracked or frost-damaged body or bonnet.
- Leaking test cocks or shutoff valves.
- An irrigation vacuum breaker spitting water every time the sprinklers start.
Irrigation leaks around the assembly can also point to a problem further down the line. See how hidden leaks are traced.
Homeowners with sprinkler systems
Many single-family homes have a testable assembly without realizing it, usually a pressure vacuum breaker on the irrigation line near the front yard. If your utility sends a test notice, that is almost always the device it means.
Vacuum breakers sit outdoors in sun and wind, and their plastic bonnets and seals wear out. A cracked bonnet leaks every time the sprinklers run, which wastes water and can fail the test. Rebuild kits are inexpensive, and a rebuild usually takes less than an hour.
Whoever tests the assembly should hold a current backflow tester certification and use a gauge that has been calibrated recently. Ask for both on the report, since utilities check them.
After a failed test: rebuild or replace
A failed test is common and usually fixable. Most assemblies are built to be serviced in place. A rebuild kit replaces the rubber seats, discs and springs that wear out, and the assembly is retested on the same visit.
Replacement makes sense when the body is cracked, parts for an older model are no longer made, or the assembly is the wrong type for the hazard it protects. A replacement assembly usually needs a permit and has to be tested again once it is installed.
Either way, the job is not finished until a passing report reaches the utility. Keep a copy of both the failed and the passing results, since they show the problem was found and fixed.
What backflow testing costs
| Factor | Why it matters |
|---|---|
| Number of assemblies | Each assembly is tested separately. |
| Assembly type | RP assemblies take longer than vacuum breakers. |
| Repairs | Rebuild kits cost less than full replacement. |
| Access | Assemblies in vaults or tight enclosures take more time. |
Compliance note: keep a copy of every test report. Utilities can follow up on missing tests, and a report on file settles the question quickly.
Want your real number? Call (714) 750-8637 and describe the job.
Backflow service nearby
We test assemblies for Mesa Water and IRWD customers across Costa Mesa, and for properties in nearby cities like Garden Grove. Businesses with several assemblies can bundle tests with commercial plumbing maintenance.
Backflow test due? We test, repair and file.
Call (714) 750-8637Backflow questions
Every year. Mesa Water requires annual testing of backflow prevention assemblies.
It is repaired or replaced and tested again. The passing report is what the utility needs.
Homes with a testable assembly, most often on irrigation, need it too. Many homes have none at all.
Yes, for businesses that cannot shut water off during the week. Call to schedule.
The account holder or the association, depending on who owns the assembly. We bill whoever you direct.