Here’s some need-to-know information for the week:

City of Boulder received state violations for failing to meet required Backflow Assembly Testing Compliance Ratio

On Feb. 24, 2023, the city received violations of the Colorado Primary Drinking Water Regulations for the 2021 and 2022 calendar years for Failed Backflow Assembly Testing Compliance Ratio. Backflow prevention assemblies prevent contamination from private properties to the city’s public water system. Most non-single-family water connections are required to have backflow prevention devices that are owned and maintained by the property owner.

Key takeaways:

  • This situation is not an emergency and does not impact public health.
  • The city is required to notify water customers of the water quality violations within 30 days of issuance from the state. The violations will be included in the 2023 Water Quality Report, which will be mailed to customers on or before March 24.
  • Boulder Revised Code requires owners of backflow prevention devices to have all devices inspected and tested annually. The city plays an enforcement role and is required by state regulations to ensure that at least 90% of devices are tested every year.
  • This required percentage has increased since the state regulations were updated, from 60% in 2016 to the current 90%.
  • In 2021, the city only received tests for 88% of devices; however, the city subsequently brought the compliance ratio up to 95% by July 2022.
  • The city also did not achieve the state requirement to have all past-due 2021 tests submitted within 90 days.
  • Through increased customer outreach and tracking, the city received more test reports in 2022 than in 2021. However, staff also conducted a quality assurance effort on our backflow data in 2022, which resulted in discovering devices that we had not previously tracked and that had not been tested recently. Therefore, the percentage of tests received in 2022 decreased to 76% despite the increased number of tests completed.
  • Backflow noncompliance is one of the most frequent types of drinking water violations that the state issues, with several Front Range communities also receiving this type of violation in the past few years.

The city is not aware of any backflow contamination due to untested devices. City staff collect water quality samples throughout the water distribution system on a weekly basis and have no evidence that drinking water was impacted.

The city has implemented process improvements, modernized our records and tracking systems and is ensuring adequate staff and contractor resources to reduce the backlog of overdue backflow tests and ensure we reach compliance in 2023.

For more information, contact Meghan Wilson, Water Quality Senior Manager, at or 303-328-7809.


Keep Reading