Cross-Connection and Backflow Prevention Program

UPDATE: Beginning May 8th, 2019, backflow test results are to be submitted through our Backflow Test Submission Portal. Paper test submissions will no longer be accepted after June 30, 2019.

If you recieve a letter stating that you are not in compliance with our testing requirements, contact a certified tester to perform the test. Then contact to obtain a pin number for your device to submit results online.

If you recieve a letter stating that you are not in compliance with our testing requirements and you do not have a backflow device installed on your water line, contact a certified plumber to install the device. An Allegheny County Health Department plumbing permit will be required for installation. After installation, a certified tester must submit the test results to PWSA through the backflow submission app.


Submit Backflow Test Results

Test results must be submitted by an ASSE Certified Tester. When creating an account, testers should have a digital copy of their ASSE Certification and Calibration Certificate for each backflow test device to upload.

The tester will recieve notifcation via email when test results have been approved by PWSA staff.



Testing Requirements

Property owners are responsible to test backflow prevention devices every 12 months at minimum. Tests are to be completed by an ASSE Certified Tester and submitted to PWSA  through our Backflow Test Submission Portal. If PWSA does not receive test results, water service may be terminated.

A property owner must also test the device and forward the results when repairs are made. 

Search for an ASSE Certified Backflow Tester

Contact our backflow team at



The Safe Drinking Water Act is a federal law that established regulations to protect water quality in the United States. The Act sets standards for municipalities to enforce. One such standard is the prevention of all backflows into the public water system. In order to prevent backflows into the public water system, commercial buildings must install a PWSA-approved backflow prevention device. Once installed, the device must be tested annually, and results forwarded to PWSA for review.

PWSA's requirement for a backflow prevention device on all commercial structures can be found in Part III Rules and Regulations – Section B Construction and Maintenance of Facilities. The tariff is subject to change pending the Pennsylvania Public Utility Commission approval. For more information regarding the tariff, read our press release



Other Regulatory Agencies

Allegheny County Health Department

The Allegheny County Health Department (ACHD) administers the Plumbing Code in the City of Pittsburgh. The Plumbing Code also regulates cross-connections and backflow devices. PWSA relies on the plumbing code for specific design specifications for approved backflow devices. 

An ACHD plumbing permit and inspection is required when installing a new backflow device. Visit their website for more information


PA Department of Enviromental Protection 

The PA DEP also mandates a backflow prevention device under state code. Please read Title 25 Pennsylvania Code, Section 109.709 for more information. 



What is a Cross-Connection?

A cross-connection is described in plumbing code as any physical connection or arrangement between two otherwise separate piping systems, one of which contains potable water and the other either water of unknown or questionable safety, whereby there exists the possibility for flow from one system to the other.

Examples of common commercial cross-connections are:

  • Carbonator for soda machine
  • Coffee and/or tea brewers
  • Chemical dispensers
  • Boilers


What is Backflow Prevention? 

A fixture that prevents the reverse flow of water from a building into the public water system. A properly installed device will prevent cross-connection contaminants from entering the water system. Common Backflow Prevention Devices include:


Reduced Pressure Valve Assembly (domestic service)


Reduced Pressure Valve Assembly (domestic service)


Why does my commercial water line need to have a device installed?

PWSA delivers quality water to all users of the system. Building owners must ensure that contaminated water from building systems does not enter waterlines and affect the health and safety of those who use the water supply. Undetected contaminants can cause illness or death.


Does my fire system supply line need to have a backflow prevention device installed?

Yes, all water lines that connect to the public water system must have a PWSA approved device installed and tested annually. PWSA recommends installing a double check valve assembly for fire service lines.


Do residential units need to have a backflow prevention device?  

Multi-family units are considered commercial properties and would need to install a device. Single-family units may need to install a device if an irrigation system is present. It is best to consult a plumber if you have an irrigation system to ensure all regulations are met.