Backflow Testing in the San Francisco Bay Area

A backflow preventer is designed to allow water to move in the intended direction while preventing reverse flow that could potentially introduce contaminants into the public water supply. Our backflow services include:

• Backflow Testing – Field testing to verify that the assembly is functioning properly.
• Testing Backflow Preventers – Testing applicable assemblies using appropriate procedures and equipment.
• Backflow Inspection – Checking the assembly’s condition, accessibility, installation, and visible components.
• Backflow Preventer Repair – Diagnosing and repairing applicable assemblies that fail testing.
• Backflow Preventer Replacement – Replacing damaged, obsolete, or non-repairable assemblies when necessary.
• Retesting – Testing repaired or replaced assemblies to verify proper operation.

If you’re searching for backflow testing near me, contact Sequoia Plumbing & Mechanical for professional service throughout the San Francisco Bay Area.

What Is Backflow Testing?

Backflow occurs when water or other substances flow in the opposite direction from their intended path. This can create a risk of contaminants entering a potable water distribution system through a cross-connection. A backflow prevention assembly is installed to help prevent this reverse flow. During backflow testing, a qualified tester evaluates the assembly to determine whether its internal components are operating correctly and providing the required protection.

Regular testing is important because a backflow preventer can appear normal from the outside while internal check valves, relief valves, seals, springs, or other components are no longer performing properly.

California Backflow Testing Requirements

California has specific requirements governing cross-connection control and backflow prevention. An important recent change is that California’s former cross-connection control regulations in Title 17 were repealed and replaced by the State Water Resources Control Board’s Cross-Connection Control Policy Handbook (CCCPH). The CCCPH became effective July 1, 2024, and the State Water Board adopted a revised version on June 17, 2025. Under the current California requirements:

• Backflow prevention assemblies covered by a public water system’s Cross-Connection Control Program must be field tested at least annually. A public water system, the State Water Board, or a local health agency can require more frequent testing for higher-hazard premises or assemblies at increased risk of failure.
• Required assemblies must also be field tested after installation, repair, depressurization for winterizing, or permanent relocation.
• Required field testing must be performed by a certified backflow prevention assembly tester. The current CCCPH requires the applicable tester certification to come from a certifying organization recognized by the State Water Board.
• A newly installed backflow prevention assembly must receive a passing field test before continuous water service is provided to the user.
• If an assembly fails its field test, the public water system must ensure it is repaired or replaced within 30 days after notification of failure, although an extension may be permitted if provided for in the water system’s Cross-Connection Control Plan.
• Air-gap separations covered by the program must be visually inspected at least annually.

These are statewide standards for California public water systems. Your local water supplier or health agency may impose additional or more frequent requirements, so property owners should follow the testing notice and instructions issued by their specific water provider.

California State Water Resources Control Board — Cross-Connection Control Policy Handbook

Testing Backflow Preventers

Different plumbing applications can require different types of backflow prevention assemblies. Professional testing backflow preventers requires understanding the specific assembly and the appropriate field-testing procedure. Common testable assemblies include:

Reduced Pressure Principle Assembly (RP)

RP assemblies provide backflow protection using two independently acting check valves with a hydraulically operated relief valve between them.

Double Check Valve Assembly (DC)

A double check assembly uses two independently acting check valves and is used where appropriate for the assessed hazard.

Pressure Vacuum Breaker (PVB)

PVB assemblies are commonly associated with protection against backsiphonage in appropriate applications, including certain irrigation configurations.

Spill-Resistant Vacuum Breaker (SVB)

SVBs provide backsiphonage protection in applicable installations and are designed to reduce water spillage during operation. The correct assembly depends on the application, degree of hazard, and requirements of the applicable public water system.

A failed test does not necessarily mean the entire assembly must be replaced. Depending on its condition, the problem may involve:

• Worn seals
• Debris inside the assembly
• Leaking shutoff valves
• Failed check valves
• Relief valve problems
• Damaged internal components
• General deterioration

When practical, the affected components may be repaired and the assembly retested. California’s current CCCPH requires public water systems to ensure failed assemblies covered by their programs are repaired or replaced within 30 days of notification unless an allowable extension applies.

How Often Is Backflow Testing Required in California?

For backflow prevention assemblies covered by California public water systems’ Cross-Connection Control Programs, the statewide minimum is at least once every year. More frequent testing can be required for certain higher-risk situations. Testing is also required following installation, repair, depressurization for winterizing, or permanent relocation of covered assemblies. Because requirements and submission procedures can differ between Bay Area water providers, always check the notice or requirements issued by your local water supplier.

Backflow Testing Price

The backflow testing price can vary depending on the property and assembly. Factors that can affect cost include:

• Type of backflow preventer
• Number of assemblies being tested
• Assembly size
• Accessibility
• Residential vs. commercial property
• Required documentation
• Whether repairs are necessary
• Whether retesting is required

For current pricing, call Sequoia Plumbing & Mechanical at (650) 880-6339.

Residential & Commercial Backflow Testing

Residential Backflow Testing

Some residential properties have backflow prevention assemblies serving irrigation or other systems where backflow protection is required. If you’ve received a notice that your backflow preventer is due for testing, we can inspect and test the applicable assembly and identify problems that may prevent it from passing.

Commercial Backflow Testing

Commercial and multifamily properties can have more complex cross-connection risks and multiple backflow prevention assemblies. We provide backflow testing services for applicable commercial systems throughout the San Francisco Bay Area, including properties such as offices, restaurants, multifamily buildings, HOAs, and other facilities.

Why Choose Sequoia Plumbing & Mechanical?

When comparing backflow testing companies, it’s important to choose a backflow testing company that understands both the testing process and the plumbing system connected to the assembly. Choose Sequoia Plumbing & Mechanical for:

• Professional backflow testing
• Residential and commercial service
• Backflow preventer inspection
• Testing of common backflow assemblies
• Troubleshooting failed assemblies
• Repair and replacement options
• Clear recommendations
• Professional Bay Area plumbing service
• Convenient online scheduling

Schedule Backflow Testing in the San Francisco Bay Area

Don’t wait until a testing deadline or failed backflow preventer becomes a larger problem. Sequoia Plumbing & Mechanical provides professional backflow testing services throughout the San Francisco Bay Area. Whether you need routine testing backflow preventers, help with a failed assembly, or professional backflow repair, we’re ready to help. Call (650) 880-6339 or request backflow testing online.