Cross Connection Control Program

The cross connection control program protects Arlington County’s water supply from contamination as required by state law. Learn more in the Virginia Administrative Code: Title 12. Health and Title 13. Housing.

A cross connection is a connection between a potable water supply (drinking water) and a non-potable source. At a cross connection, it is possible for contaiminants to enter the drinking water. The installation of plumbing backflow devices prevents contaminants from entering the drinking water. 

The cross connection control program requires restaurants and commercial buildings to install backflow devices on their pipes. The County inspects restaurants and commercial buildings annually for cross connection control compliance. 

The County inspects residential irrigation systems and other potential cross connections on residential properties after installation. After the first inspection, the owner may hire third-party inspectors – but there is not a requirement to do so.

Plumbing permits that include a backflow device require a final cross connection inspection before the plumbing permit can be finaled. A final cross connection inspection may not be scheduled until a cross connection application is submitted. Information for submitting the application can be found in the FAQs below.  

Note: If a cross connection on your premises contaminates public drinking water, you are legally liable for the ensuing damages. Arlington’s cross connection control program helps avoid this outcome.

Frequently Asked Questions

What is a backflow?

A backflow (backpressure or back siphonage) is a reversal of the flow of non-potable water or other substances through a cross connection and into the piping of a public water system. A sudden change in water pressure in the pipes could cause such a reversal. The reversed water flow could then exert suction that draws contaminated water into the drinking water.

If I’ve received a notice about an upcoming cross connection control compliance inspection, how should I prepare?

Prior to scheduling an inspection with the County, you should have the backflow devices on your property tested by a Virginia-licensed backflow device professional. Once testing is complete, follow the instructions on the notice to create the cross connection application. Update the device information and include any additional devices. 

What if an inspector cannot complete an inspection or confirm compliance during the initial inspection?

If an inspector determines the device is not in compliance or the device inspection information has not been updated, the inspection will be rejected. The inspection will automatically be rescheduled 14 days after the date of the rejected inspection. 

How do I submit a cross connection application?

  1. Register or log in to Permit Arlington (step-by-step video tutorials and help are available here)
  2. From the dashboard, hover over the Create drop-down menu (upper-right corner) and select Building Application. 
  3. Select Cross Connection followed by Continue Application. 
  4. Fill out the details in the form and submit the application.