Through the U.S. Environmental Protection Agency and under the Safe Drinking Water Act, Lead and Copper Rule (commonly abbreviated as LCR), public drinking water systems, like Denver Water, are required to test tap water directly from homes likely to have high lead levels within their service area. These are homes with known lead service lines and plumbing. 

The EPA rule requires that nine out of 10, or 90 percent, of the sampled homes must have lead levels below the action level of 15 parts per billion (ppb). To put it in context, one part per billion is like one dollar out of one billion dollars. The action level is an indicator that additional steps may be needed to optimize corrosion control treatment. This means a utility may need to adjust its water treatment to minimize the risk of lead getting into drinking water from lead pipes and plumbing.

In 2012, water test results from homes with known lead service lines and plumbing in Denver Water’s service area exceeded the EPA action level. This is how the Lead Reduction Program, Denver Water’s holistic, alternative approach to more traditional methods of corrosion control, came to be; the program was approved by the EPA and Colorado Department of Public Health & Environment in December 2019 and launched in 2020.

In 2024 and 2025, several updates to the Lead and Copper Rule will take place that will change some of the ways Denver Water samples for lead, the action level and how we inform customers. We will update this page as more information becomes available.