The Town of Clifton has no public water system and its homes rely on private wells, so Fairfax Water's yearly backflow testing program reaches only properties in the wider Clifton area that are Fairfax Water customers. A well home still needs protection on sprinkler and pool lines. Call the number on this page to be connected with a local plumber in Clifton.

Signs you should call about backflow in Clifton
- You are adding a sprinkler system, pool fill or garden hydrant to a well-fed house
- A hose or fertilizer sprayer is connected straight to an outdoor spigot with no vacuum breaker
- You are on Fairfax Water and the sprinkler assembly has not been tested in over a year
- Water drips from an existing device or the body cracked in a freeze
- A well test or a change in taste suggests something got into the household water
Local conditions in Clifton
Clifton is a tiny historic village, a National Historic District since 1984, in southwestern Fairfax County, with wooded lots, Popes Head Creek and horse country to the north. The median home was built around 1940. The Town has no water system, and its rules require a new house on a vacant lot to have room for a water well and an onsite wastewater field; public sewer is available only to existing buildings that meet Fairfax County guidelines. So inside the Town, backflow is a question of protecting your own well and plumbing, not of meeting a utility's testing schedule.
The 20124 ZIP code is much larger than the Town, and some homes in it may be Fairfax Water customers. Those homes fall under Fairfax Water's cross-connection program, run with Fairfax County Land Development Services: testable assemblies on irrigation, pools and directly connected hot tubs are tested at installation, after repairs and at least yearly by a DPOR-certified tester on the County's list. Permits in the Town go through Fairfax County, but the Mayor or a designee must sign the application before it goes to the County.
What affects the cost
- Evaluation versus test. Planning protection for a well-fed irrigation system takes longer than a routine test.
- Device choice. A simple hose-bib vacuum breaker costs far less than a reduced pressure assembly.
- Old plumbing. Older houses may need piping changes to fit a device properly.
- Permits. New work involves the Town signature and a County permit.
What happens when you call
You are connected with an independent plumber who works around Clifton. Say whether you are on a well or Fairfax Water, what you want to protect and whether anything is leaking now. If you are on Fairfax Water, ask the plumber to confirm their certification and County listing.
Backflow Testing questions in Clifton
My house is on a private well. Does backflow still matter?
How can I tell which water utility serves my address?
Is a permit needed to install or replace a backflow preventer?
Why does a lawn sprinkler system need a backflow preventer?
More plumbing services in Clifton
Backflow Testing nearby
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