Backflow testing in Northern Virginia: which county are you in?

You just got a notice about backflow testing, and you're staring at it wondering what a backflow preventer is and why you suddenly have to get it tested. Most Northern Virginia homeowners don't know they own one until that notice arrives.

The short answer: a backflow preventer is a one-way valve on your water line, your water provider requires it to be tested every year, and the test takes about 30 minutes. Ignoring the notice isn't an option. Utilities can and do shut off water service for non-compliance. The good news is that it's easy to handle once you know what's involved.

What is a backflow preventer, and where is yours?

A backflow preventer stops water from flowing backward into the public water supply. It's a one-way valve that protects everyone's drinking water from whatever might be sitting in your irrigation lines, fire sprinkler system, or other equipment.

You'll usually find it in one of these spots:

• Near your water meter, or where the irrigation line leaves the house
• On the supply line to an irrigation system
• At a fire sprinkler system connection
• On a boiler system or commercial equipment

If you have an underground sprinkler system, you very likely have one. Townhouses and condos with fire sprinkler systems often do too.

What happens during the test

The test itself takes about 30 minutes. Our technician:

• Briefly isolates the assembly from the water supply
• Tests the internal mechanisms of the backflow preventer
• Checks pressure differentials and valve function
• Documents the results on the official form
• Submits the test report to the county or water utility that sent the notice

That last step is the one most people are glad to hand off. If your device passes, you're done for the year. If it fails, it has to be repaired and re-tested within the deadline on your notice.

How each county handles it

Your water provider requires annual testing of testable assemblies, and your notice tells you when. The details vary by jurisdiction.

Fairfax County

In Fairfax County, each property is assigned a testing month based on its tax map grid. You can't just pick a month, and neighbors on the same street can have different testing months.

If your assembly fails in Fairfax County, it must be repaired and re-tested within 10 business days of the failed test.

Loudoun County

In Loudoun County, the program is run by Loudoun Water, which requires annual testing of testable assemblies on fire and irrigation systems. That reaches a lot of homes in newer developments where irrigation systems are common.

Arlington, Alexandria, and Prince William County

Arlington and Alexandria and Prince William County are each served by their own water utilities, with their own notices and schedules. The annual test requirement for testable assemblies is the same. Your notice spells out your deadline.

Who can test your backflow preventer?

Virginia requires backflow testers to hold certification through DPOR (the Department of Professional and Occupational Regulation). The test takes specialized equipment, and the results have to be documented properly for compliance.

Pioneer Plumbers holds Backflow License #2717059632, and our technicians have the certified equipment to test the backflow preventers used in Northern Virginia homes and businesses. Backflow testing and repair is part of our diagnostics and specialty services.

Why backflow preventers fail

Backflow preventers fail for predictable reasons in this climate:

• Freeze damage from winter temperature swings
• Debris buildup in the check valves
• Worn rubber seals and gaskets
• Calcium buildup from our hard water

Repair cost depends on which components need replacing, and on whether the assembly can be repaired or needs to be replaced entirely. We give a written, upfront quote before any work begins.

Don't wait for the last week

Notices usually arrive well before the deadline, and that lead time is worth using. Certified testers get booked up quickly, especially in busy months, so don't wait until the last week to call.

If you've got a notice in hand or can't find your backflow preventer, call Pioneer Plumbers at (703) 508-3088. We'll test it, file the report with the county or utility, and handle any repairs it needs.