# Failed Backflow Test in California: Next Steps

> A failed backflow test in California must be repaired or replaced within 30 days, then retested. The steps, records, and when service can be shut off.

Source: https://www.exoduswater.com/post/what-happens-if-a-backflow-test-fails-california

Cross-connection & backflow October 30, 2026Exodus Water Services 

# What Happens If a Backflow Test Fails in California?

A failed backflow test in California must be repaired or replaced within 30 days, then retested. The steps, records, and when service can be shut off.

**Short answer:** If your backflow assembly fails its test in California, it must be **repaired or replaced within 30 days** of the notice of failure, and then **tested again** by a certified backflow prevention assembly tester. Your water supplier may allow an extension only if its Cross-Connection Control Plan provides for one. If the assembly is not fixed, the water supplier can use its program rules to act, which can include discontinuing water service. These rules come from the State Water Board’s Cross-Connection Control Policy Handbook (CCCPH), sections 3.3.3 and 3.1.3.

A failed test is common and usually fixable. It does not mean contaminated water reached the public system. It means the assembly is not working as designed and needs attention before it can be relied on. This guide walks through what happens next and how to avoid a shutoff.

## What a “failed” backflow test means

During a field test, the certified tester uses calibrated gauges to check each part of the assembly against the procedure for that type. The CCCPH’s performance exam for testers is built around the same failure modes: leaks in shutoff valves, and failures in check valves, air inlet valves, or relief valves (CCCPH 3.4.1(b)(2)). A failed test usually points to one of these:

| Assembly type                         | Parts that can fail the test                                                    |
| ------------------------------------- | ------------------------------------------------------------------------------- |
| Reduced pressure principle (RP, RPDA) | First or second check valve, differential pressure relief valve, shutoff valves |
| Double check (DC, DCDA)               | First or second check valve, shutoff valves                                     |
| Pressure vacuum breaker (PVB)         | Check valve, air inlet valve, shutoff valves                                    |
| Spill-resistant vacuum breaker (SVB)  | Check valve, air inlet valve, shutoff valves                                    |

The parts listed for each type match the CCCPH definitions of each assembly (CCCPH 3.1.1). Learn more about each one in our [guide to the types of backflow preventers](https://www.exoduswater.com/post/types-of-backflow-preventers) .

## Step by step: what happens after a failed test

1. **The tester records the failure.** The test report notes which part failed. Water suppliers must keep the results of all field tests, including the tester’s name, test date, repair date, and certification number, for the previous three calendar years (CCCPH 3.5.1(a)(4)).
2. **The water supplier is notified.** The failure is reported under the supplier’s program procedures. The 30-day clock runs from notification of the failure (CCCPH 3.3.3(e)).
3. **The assembly is repaired or replaced.** This has to happen within 30 days, unless the supplier’s Cross-Connection Control Plan allows an extension (CCCPH 3.3.3(e)).
4. **The assembly is retested.** Every assembly must be field tested after a repair, and the test must be done by a certified tester (CCCPH 3.3.3(a)). The California Plumbing Code also requires a test at the time of repair (CPC 603.4.2).
5. **The passing report is filed.** The water supplier records the repair and the passing result. Suppliers must keep records of repairs, replacements, and relocations for the previous three calendar years (CCCPH 3.5.1(a)(5)).

## The 30-day repair rule

The rule is in CCCPH 3.3.3(e): the water system “must ensure that BPAs that fail the field test are repaired or replaced within 30 days of notification of the failure.” Extensions “may be allowed by the PWS if included as part of the Cross-Connection Control Plan.”

Two practical points:

- **Thirty days is the state maximum, not a guarantee.** Your supplier’s notice will give your actual deadline. Read it as soon as it arrives.
- **Ask early if you need more time.** If a replacement assembly is on back order or the work needs a permit, contact your water supplier before the deadline and ask whether its plan allows an extension.

## Repair or replace?

Many failures are fixed by repairing internal parts. Replacement makes sense when the assembly is damaged, when parts are not available, or when the assembly is no longer the right type for the hazard. Keep these rules in mind:

- **A replacement must be an approved assembly.** Each new or replacement PVB, SVB, DC, and RP must be approved through laboratory and field evaluation under the USC Foundation for Cross-Connection Control and Hydraulic Research standards or ASSE International standards (CCCPH 3.3.1(b)).
- **Do not modify the assembly.** An approved assembly must not be modified after approval, and water systems must require testers to report a modified assembly (CCCPH 3.3.1(c)).
- **High hazard properties may need an upgrade.** Some high hazard premises with an existing double check installed before July 1, 2024, may keep it under conditions, including that it passes all field tests within the timeframe in the supplier’s plan. An air gap, RP, or both is required for **all new or replacement** installations at those premises after July 1, 2024 (CCCPH Appendix D). If your DC at a high hazard site fails and has to be replaced, expect to install an RP or air gap. See [RPZ backflow preventer explained](https://www.exoduswater.com/post/rpz-backflow-preventer-explained) .
- **New installations have placement rules.** A replacement RP must sit at least 12 inches and no more than 36 inches above grade unless the water system approves otherwise, and RPs or DCs installed after the handbook was adopted need side clearance for testing (CCCPH 3.3.2(b) and (f)).

## When can my water be shut off?

There are two different situations.

### You do not repair or retest in time

Every water system’s cross-connection control program must include rules giving it legal authority to act when a water user fails to comply with requirements for installing, inspecting, testing, or maintaining a required assembly. The program must allow at least one of these: deny or discontinue water service, install, inspect, test, or maintain the assembly itself, or otherwise address the failure in a timely manner (CCCPH 3.1.3(a)(1)).

How a specific supplier uses that authority is in its own rules. For example, LA County Waterworks Districts issues a shut-off notice to customers who do not arrange a test by the due date, and may terminate service until the assembly is tested and the completed form is submitted ([LA County Public Works](https://dpw.lacounty.gov/core-service-areas/water-resources/waterworks-districts/backflow-prevention/) ).

### The tester finds an actual backflow incident

This is rare but serious. Testers must notify the water system as soon as possible, within 24 hours, if they observe a backflow incident or an unprotected cross-connection during testing. The water system must investigate immediately and **discontinue service** if a backflow incident is confirmed. Service is not restored until the water system receives a passing field test and the assembly is protecting the public water system (CCCPH 3.3.3(f)).

The water system must also notify the State Water Board and local health agencies of any known or suspected backflow incident within 24 hours (CCCPH 3.5.3(a)).

## What records you should keep

Your water supplier keeps the official record, but you should keep your own copy of:

- The failed test report, showing which part failed.
- The repair invoice or replacement details, including the new assembly’s make, model, size, and serial number. Suppliers record these for every assembly (CCCPH 3.5.1(a)(2)).
- The passing retest report, with the tester’s certification number.
- Any correspondence with your supplier about deadlines or extensions.

Good records make next year’s test simpler and help if a deadline is ever disputed.

## How to keep the next test from failing

- **Test on time every year.** Annual testing is the minimum, and suppliers can require more frequent testing for high hazard premises or assemblies at increased risk of failure (CCCPH 3.3.3(b)).
- **Keep the assembly accessible.** Every assembly must be accessible for testing, inspection, and maintenance (CCCPH 3.3.2(h)).
- **Test after winterizing.** An assembly depressurized for winterizing must be tested again (CCCPH 3.3.3(a)).
- **Do not bypass or remove it.** A required assembly protects the public water system, and removing it creates the exact hazard the program exists to prevent.

## How Exodus Water Services handles failed tests

Exodus Water Services is based in Thousand Oaks. Our certified testers test RP assemblies, double check valve assemblies, pressure vacuum breakers, spill-resistant vacuum breakers, and air gaps. When an assembly fails, we coordinate the repair with a licensed contractor and retest it, so you get a passing report for your records and your water supplier. See [backflow testing services](https://www.exoduswater.com/backflow) , or read the [full guide to backflow testing in California](https://www.exoduswater.com/post/backflow-testing-california-property-owner-guide) . For costs, see [what affects backflow test cost](https://www.exoduswater.com/post/backflow-test-cost-california) .

## Frequently asked questions

**How long do I have to fix a failed backflow test in California?**30 days from notification of the failure, unless your water supplier’s Cross-Connection Control Plan allows an extension (CCCPH 3.3.3(e)). Your notice will list your deadline.

**Does a failed backflow test mean my water is contaminated?**Not by itself. It means the assembly is not working as designed. If the tester sees signs of an actual backflow incident, the tester must notify the water system within 24 hours and the system must investigate (CCCPH 3.3.3(f)).

**Do I need a retest after a backflow repair?**Yes. Every assembly must be field tested after a repair, by a certified backflow prevention assembly tester (CCCPH 3.3.3(a)).

**Can my water be shut off for a failed backflow test?**It can if you do not repair and retest as required. Water systems must have authority to deny or discontinue service, or take other corrective action, when a customer does not comply (CCCPH 3.1.3(a)(1)). Service must be discontinued if a backflow incident is confirmed (CCCPH 3.3.3(f)).

**Can I replace a failed double check with another double check?**Only if your property is low hazard. At high hazard premises, all new or replacement installations after July 1, 2024, must be an air gap, an RP, or both (CCCPH Appendix D).

**Who can repair a failed backflow assembly?**Your water supplier’s rules and local permitting decide who may perform repairs. The retest after the repair must be done by a certified backflow prevention assembly tester (CCCPH 3.3.3(a)).

**How long are failed and passing test records kept?**Water suppliers keep field test results and repair records for the previous three calendar years (CCCPH 3.5.1(a)(4) and (5)). Keep your own copies too.

Last reviewed: October 30, 2026.

## Sources

- State Water Board, [Cross-Connection Control Policy Handbook, April 2026 revision (PDF)](https://www.waterboards.ca.gov/drinking%5Fwater/certlic/drinkingwater/docs/2026/cross-connection-control-policy-handbook-apr-2026.pdf) : sections 3.1.1, 3.1.3, 3.3.1, 3.3.2, 3.3.3, 3.4.1, 3.5.1, 3.5.3, and Appendix D
- State Water Board, [Cross-Connection Control Policy Handbook page](https://www.waterboards.ca.gov/drinking%5Fwater/certlic/drinkingwater/cccph.html)
- IAPMO, [2025 California Plumbing Code (read-only edition)](https://epubs.iapmo.org/2025/CPC/) : section 603.4.2
- Los Angeles County Public Works, [Waterworks Districts backflow prevention](https://dpw.lacounty.gov/core-service-areas/water-resources/waterworks-districts/backflow-prevention/)

Have a failed test to resolve? Call (805) 991-7333 or [request a review](https://www.exoduswater.com/contact-us?service=backflow) .

## How Exodus can help

- Related service [Backflow testing services ](https://www.exoduswater.com/backflow)
- Free tool [CCCP Readiness Assessment ](https://www.exoduswater.com/tools#cccp-assessment)

[Request a Compliance Review](https://www.exoduswater.com/contact-us?service=backflow) [(805) 991-7333](tel:+18059917333) 

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