Denver Water Board, CO
Lead detected, under the action levels
Latest 90th-percentile lead: 3.6 ppb (monitoring period 2026-2026). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. Lead was measured in sampled homes but the 90th percentile is under both action levels. EPA's health goal for lead is zero, so test your own tap if your home was built before 1986 or anyone in it is pregnant or a young child.
Denver Water Board at a glance
Denver Water Board serves about 1,287,000 people through 311,339 service connections, which makes it a very large system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws surface water, in Denver County, Colorado. EPA system ID: CO0116001; phone on file: 303-994-6605. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
Against the period ending 2025 (3.1 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Denver Water Board is 11 ppb across 21 monitoring periods, none of them over 15 ppb (4 over 10 ppb).
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 3.6 ppb |
| 2025 | 3.1 ppb |
| 2025 | 3.9 ppb |
| 2024 | 3.6 ppb |
| 2024 | 4 ppb |
| 2023 | 3.9 ppb |
| 2023 | 3.5 ppb |
| 2022 | 3.8 ppb |
| 2022 | 3.9 ppb |
| 2021 | 4.5 ppb |
| 2021 | 4.1 ppb |
| 2020 | 4.1 ppb |
| 2020 | 6.7 ppb |
| 2019 | 11 ppb over 10 |
| 2019 | 10 ppb |
| 2018 | 11 ppb over 10 |
| 2018 | 11 ppb over 10 |
| 2017 | 10 ppb |
| 2017 | 11 ppb over 10 |
| 2016 | 10 ppb |
| 2016 | 10 ppb |
How Denver Water Board compares
Of the 1,025 Colorado systems with a lead result, the median latest reading is 1 ppb; 2 are over 15 ppb right now and 71 have gone over at some point. Denver Water Board's 3.6 ppb sits at the 88th percentile in Colorado and the 86th nationally (higher means more lead).
Neighbouring systems
3 other systems share Denver County; 0 of them have a higher latest lead result than Denver Water Board. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Cherry Creek Valley Wsd | 22,000 | - |
| Advenir French Quarter | 3,447 | 0 (not detected) |
| Aspen Terrace Mobile Park | 200 | 0 (not detected) |
Your move
Test your own tap with a certified lab first-draw sample; Denver, CO may offer free or low-cost kits through the utility. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Denver Water Board whether it covers that cost before hiring anyone - many utilities now do.
These figures describe homes the utility sampled, not your tap. Only your service line record or a test of your own water answers the question for your house. What a 90th-percentile result does and does not tell you: how to read a lead result. The action level is dropping - the 10 ppb rule from 2027.