Washington’s cross-connection control rule, WAC 246-290-490, requires every backflow prevention assembly your water utility relies on to be tested when it’s installed, after any repair, reinstallation or relocation, and at least once a year after that. Your utility enforces it — which is why the notice shows up in your mailbox.
What happens during a test
- Locate & inspect. We find the assembly (meter box, irrigation riser, mechanical room, fire riser), confirm the make, model, size and serial number, and check that it’s an approved model installed the right way.
- Connect the gauge. A differential-pressure test kit — verified for accuracy at least annually — connects to the assembly’s test cocks.
- Run the field test. We follow the USC Foundation for Cross-Connection Control field test procedures, the method Washington DOH requires. Each check valve, relief valve or air inlet is measured against its pass criteria.
- Record everything. Readings go on the official field test report along with the information WAC 246-292-036 requires — assembly details, test kit info, results, and any repairs.
- File it. We submit the report to your utility through the system it uses, and email you a copy with photos.
Most assemblies take 15–30 minutes. Water is off for a few minutes per assembly while we test.
What “pass” means
| Assembly | Passes when |
|---|---|
| DCVA / DCDA | Each check valve holds at least 1.0 psid; the #2 shutoff is tight. |
| RPBA / RPDA | Relief valve opens at 2.0 psid or more; check #1 holds well above the relief opening point; check #2 is tight against backpressure. |
| PVBA / SVBA | Air inlet opens at 1.0 psid or more (and fully); check valve holds at least 1.0 psid. |
Not sure what you have? See every assembly type and how to tell them apart →
We don’t just test — we look. If an assembly is the wrong type for the hazard, installed below grade where it shouldn’t be, or a PVB sits lower than the sprinkler heads it serves, we’ll note it and explain it. That’s the stuff that turns into an expensive surprise later.
Who needs annual testing
- Homes with lawn irrigation — the most common reason a homeowner gets a test notice.
- Homes and buildings with fire sprinklers on a combined or separate fire service.
- Commercial buildings — restaurants, salons, clinics, dental offices, labs, car washes, breweries and anything with chemical, boiler or process water.
- Multifamily and mid-/high-rise buildings — many Puget Sound utilities require premises isolation on tall buildings.
- Waterfront properties with water-powered boat lifts, pools or docks.
