Backflow Testing in NYC: Requirements and How It Works

If your building in New York City has a backflow prevention device, you are required by law to have it tested annually. The NYC Department of Environmental Protection (DEP) enforces this requirement to protect the city's public water supply from contamination. Failing to comply can result in fines, violations, and even loss of water service.

At Karl's Plumbing, Heating & Cooling, our Licensed Master Plumbers and certified backflow testers have been keeping NYC buildings compliant since 1935. Here is everything you need to know about backflow testing in New York City.

What Is Backflow?

Backflow occurs when water flows in the opposite direction from its intended path through the plumbing system. Instead of flowing from the city's clean water supply into your building, contaminated water from your building flows backward into the public water main. This can happen due to a sudden drop in water pressure (called back-siphonage) or when pressure in your building's system exceeds the pressure in the city main (called back-pressure).

Backflow can introduce dangerous contaminants into the drinking water supply, including chemicals, bacteria, pesticides, and other hazardous substances. This is why the DEP takes backflow prevention so seriously.

Why Is Backflow Testing Required in NYC?

The New York City DEP Cross Connection Control Program mandates that all buildings with backflow prevention devices have them tested annually by a certified tester. This requirement is part of the city's broader effort to protect the public water supply under the New York State Sanitary Code and the Rules of the City of New York.

Buildings that are classified as posing a risk to the public water supply, which includes most commercial properties, industrial facilities, buildings with boilers, buildings with irrigation systems, and many residential buildings, must have backflow prevention devices installed and tested.

Types of Backflow Prevention Devices

There are several types of backflow prevention devices, each designed for different risk levels and applications:

Reduced Pressure Zone (RPZ) Assembly

The RPZ is the most robust and commonly required backflow preventer in NYC. It provides the highest level of protection and is required for high-hazard connections where contamination could pose a health risk. RPZ assemblies have two independently operating check valves with a pressure-monitored relief valve between them. If either check valve fails, the relief valve opens and discharges water to prevent backflow. RPZ assemblies are required to be installed in accessible locations and must be tested annually.

Double Check Valve Assembly (DCVA)

The DCVA provides protection for low-to-moderate hazard connections. It consists of two independently operating check valves. While less protective than an RPZ, it is suitable for applications where the risk of contamination is lower, such as fire sprinkler systems with no chemical additives.

Pressure Vacuum Breaker (PVB)

A PVB is used primarily for irrigation systems and outdoor water connections. It protects against back-siphonage but not back-pressure. PVBs must be installed at least 12 inches above the highest downstream outlet and cannot be used in enclosed spaces where flooding from discharge could be a concern.

The Backflow Testing Process

Backflow testing is a straightforward process when performed by a qualified professional. Here is what to expect:

1. Pre-test inspection. The certified tester visually inspects the device for leaks, corrosion, damage, and proper installation. They verify the device make, model, serial number, and size.
2. Test kit connection. The tester connects a differential pressure test kit to the test cocks on the backflow device. This specialized gauge measures pressure differences across the check valves and relief valve.
3. Check valve testing. Each check valve is tested independently to ensure it holds against backflow. The tester verifies that each valve closes tightly and holds the required minimum pressure differential.
4. Relief valve testing (RPZ only). For RPZ assemblies, the tester verifies that the relief valve opens at the correct pressure differential and that it operates properly when either check valve is forced open.
5. Results and documentation. The tester records all readings on a test report. If the device passes, the report is submitted to the NYC DEP. If it fails, the tester documents the failure and the device must be repaired and retested.

The entire testing process typically takes 15 to 30 minutes per device. During testing, water service to the building may be briefly interrupted.

Consequences of Non-Compliance

Failing to have your backflow devices tested annually can result in serious consequences:

• DEP violations. The DEP issues violations to buildings that fail to submit annual test reports. These violations carry fines that can reach thousands of dollars.
• OATH hearings. Unresolved violations may be referred to the Office of Administrative Trials and Hearings (OATH), where penalties are assessed.
• Water service termination. In severe cases of non-compliance, the DEP has the authority to terminate water service to the building until backflow devices are tested and certified.
• Liability. If a backflow incident contaminates the public water supply, the building owner can be held liable for damages and remediation costs.

If you already have a violation for backflow non-compliance, our team can help with violation removal and get your building back into compliance.

How to Schedule Backflow Testing

Scheduling your annual backflow test is simple. At Karl's Plumbing, Heating & Cooling, our licensed and certified backflow testers handle the entire process:

1. We schedule a convenient appointment at your building.
2. Our certified tester performs the annual test on all devices.
3. We submit the completed test reports directly to the NYC DEP on your behalf.
4. If any device fails, we provide a repair estimate and can complete the work immediately in most cases.
5. We send you copies of all test reports for your records.

Our Licensed NYS Backflow Tester, Pasquale Marino (#9720), ensures every test meets DEP standards. We service all five boroughs, Long Island, and Westchester.

When to Call a Licensed Master Plumber

You need a professional for backflow testing and prevention when:

• Your annual test is due or overdue.
• You received a DEP violation notice for backflow non-compliance.
• Your backflow device is leaking, making noise, or showing signs of wear.
• You need a new backflow prevention device installed.
• You are opening a new business or renovating a building and need a cross-connection survey.

Karl's Plumbing, Heating & Cooling has been protecting NYC's water supply for four generations. Our Licensed Master Plumbers (LMP #921 and LMP #2060) handle everything from annual testing to new device installations and DOB compliance. Call us at (800) 721-3200 or (718) 263-8600 to schedule your backflow test today.