Westminster requires annual tests on commercial, irrigation, fire, and domestic assemblies, filed online for the city.
Westminster backflow rules at a glance
| Water provider | City of Westminster, Cross-Connection Control and Backflow Prevention Program |
|---|---|
| Who needs an assembly | All commercial, industrial, domestic, irrigation, and fire line services. Multi-family and single-family homes are assessed by site hazard, such as a well or pond. |
| How often | At installation and every year after, by a certified backflow prevention assembly tester |
| How reports are filed | Online through BSI Online, reported to the city's Cross-connection Control team |
| Program contact | 303-658-2477, backflow@westminsterco.gov |
Summarized from City of Westminster's published program information (source), checked October 2026. The notice from your water provider always has the final word on your due date.
What we do on a Westminster backflow test
- Confirm the assembly type, size, and serial number against your provider's records
- Test every check valve and relief valve with a differential pressure gauge calibrated October 2026 and traceable to NIST
- Tag the assembly with the service date, our business information, and the tester's certification number
- File the completed report the way City of Westminster requires
- Send you a copy of the report, with photos
If the assembly fails
Most failures come down to a dirty or worn check valve, a tired relief valve, or a split rubber part. Those get cleaned or rebuilt and retested, usually in the same visit, after you approve the price. If the body itself is cracked, usually from a missed winterization, the assembly has to be replaced. Replacing an assembly is installation work, which in Colorado needs a licensed plumber; we'll tell you exactly what's needed and do the retest once it's in.
Before we come out
- Have the notice from your water provider handy, or send a photo of it when you book
- Tell us where the assembly is, and leave any gate unlocked or the mechanical room open
- For sprinkler assemblies, the water needs to be on. If the system is still winterized, we can do the spring startup and the test in one visit.
Not sure what kind of assembly you have? PVB vs. DCVA vs. RPZ →
Backflow testing nearby
Denver · Aurora · Thornton · Arvada · Northglenn · Broomfield · Golden · Lakewood · Englewood · Commerce City · Wheat Ridge · Parker · Boulder · Louisville · Lafayette · Greenwood Village · Centennial · Commercial & HOA testing · For plumbing & irrigation companies · Every provider's rules
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