Backflow testing in Nokesville.

Prince William Water sends the yearly backflow notice, and it only keeps records on devices hooked to its own pipes. In 20181 that leaves most houses out. On the utility’s own maps, fewer than one in ten single-family houses with a Nokesville address sits within 200 feet of one of its water lines, and there’s no distribution main at all inside the village. So if you’ve owned here for years and never seen the letter, nothing slipped through the cracks.

The north edge of the ZIP is the exception. Ashley Ridge, recorded from 2000 to 2002 on streets like Rain Slicker Place, Puddle Place and Aqua View Court, runs on Prince William Water mains, and the county’s address list counts it in the Linton Hall Census area, with most of Bristow. A house there with sprinklers gets the letter like any public water customer, and the passing report has to reach the utility’s Cross Connection Coordinator. Sprinklers often came with houses of that age, so the PVB by the foundation may be the builder’s, now more than twenty years on.

In the village, a Prince William Water bill can fool you. The utility runs a low-pressure sewer through the middle of town, and on 54 of its service records it notes the house as sewer only, with a well connection. That bill covers what goes down the drain. The water you drink still comes up from your own well, so there’s no device on the utility’s books and no notice on the way.

A well doesn’t take the sprinklers off the hook, though. Prince William County wants a backflow device on every lawn sprinkler system, because its job is keeping fertilizer and yard water out of the drinking water inside the house, and on a well that water is all you’ve got. Putting one in takes the county’s Limited Service and Repair Permit and an inspection. Keep the heads on your own land, too: on a road with ditches instead of curbs, the county’s rule of thumb puts the right-of-way about 15 feet from the pavement.