Boulder wants every report in its online portal within 10 days of the test, and failures within 24 hours.
Boulder backflow rules at a glance
| Water provider | City of Boulder Utilities, Backflow Prevention Program (Boulder Revised Code 11-1-25) |
|---|---|
| Who | Commercial, industrial, irrigation, fire, and multi-unit residential lines. Buildings with nine or more units must comply; three to eight units may qualify for an exemption. Single-unit homes and duplexes are generally exempt unless there's an auxiliary water source, a dedicated irrigation or fire line, or another hazard. |
| How often | Every year |
| Deadlines | Report within 10 days of the test. Failing tests within 24 hours. |
| How reports are filed | Online only, in the city's backflow portal, by a certified tester with their own login. The paper form isn't required. No filing fee is listed. |
| Failed assemblies | Repair or replace as soon as possible. If it will take more than 30 days, notify the program and set up a compliance plan. |
| If you ignore it | A $59 shut-off warning hangtag, a $113 shut-off fee, and additional penalties of $250 to $1,500 |
| Singer Plumbing Co. | Registered tester in the City of Boulder's backflow portal (approved October 2026). We enter your report for you. |
| Program contact | 303-413-7401 · nobackflow@bouldercolorado.gov |
Summarized from City of Boulder Utilities's published program information (source), checked October 2026. The notice from your water provider always has the final word on your due date.
Got a hangtag?
Once Boulder hangs a shut-off warning, it starts shut-offs if it doesn't get the required tests, or hear from the owner, within 10 days. Call us as soon as you see it. If the city has asked for the test within two business days, tell us when you book.
The city doesn't recommend testers
Boulder doesn't keep a list of recommended testers. It checks each tester's certification against its records when they register in the portal, and only certified testers can enter reports. Ask anyone you hire whether they can file in Boulder's portal. Singer Plumbing Co. is registered there.
What we do on a Boulder 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 Boulder Utilities 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 · Westminster · Arvada · Northglenn · Broomfield · Golden · Lakewood · Englewood · Commerce City · Wheat Ridge · Parker · Louisville · Lafayette · Greenwood Village · Centennial · Commercial & HOA testing · For plumbing & irrigation companies · Every provider's rules
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