Is Denver, CO tap water safe?
Supplied by Denver Water Board · serves 1.3 million people (311,339 connections) · Surface water · EPA ID CO0116001
Data: U.S. EPA · How we read the data · How we check it
Most of Denver gets its water from Denver Water Board. Parts of the city are served by 2 smaller systems: Advenir French Quarter Water System (3,447 people), Garden Meadows Water System (250 people). Your water bill names your system.
Summary
No federal limits exceeded in EPA data.
- PFAS
- Not detectedNone of 29 PFAS found above EPA's reporting limits in 15 samples (2023–2025).
- Lead
- Below action level3.6 ppb (parts per billion) at the 90th percentile: 9 in 10 homes sampled were at or below it. Action level 15 ppb, falling to 10 ppb in Nov 2027. Monitoring period ending Jun 2026. Your home's pipes can make yours higher.
- Violations
- None health-basedNo health-based violations since 2016.
- Built before 1986, or not sure what your service line is made of? Check your service line and test your tap. Utility data can't show your pipes.
- Tested your own tap? Compare your result with these numbers. Moving? Compare this system with another.
- Read Denver Water Board's 2026 water quality report (Consumer Confidence Report, from the utility). It lists every regulated contaminant tested, including ones not on this page. Questions: (303) 994-6605.
PFAS (“forever chemicals”)
EPA UCMR 5: 4 entry points tested Mar 2023 to Apr 2025. "Average" is the highest entry-point average (non-detects counted as zero), the way EPA compares UCMR 5 results to the limits. ppt = parts per trillion. These results do not determine compliance.
| Contaminant | Highest average |
|---|---|
| PFOA Not detected Limit 4 ppt | – |
| PFOS Not detected Limit 4 ppt | – |
| PFHxS Not detected Limit 10 ppt | – |
| PFNA Not detected Limit 10 ppt | – |
| HFPO-DA (GenX) Not detected Limit 10 ppt | – |
| Hazard Index (a combined score for PFHxS, PFNA, GenX and PFBS, where above 1 is over the limit) Not detected Limit 1 | – |
| PFBS Not detected Guideline 2,000 ppt | – |
| PFBA Not detected Guideline 6,000 ppt | – |
| PFHxA Not detected Guideline 3,000 ppt | – |
29 PFAS tested, 0 detected at least once. "Not detected" means below EPA's reporting limit (about 2 to 20 ppt depending on the chemical), not proven zero. PFAS not listed were not detected. The limits for PFHxS, PFNA, GenX and the Hazard Index were proposed for rescission in May 2026. That proposal is not final. Systems have until 2029 to meet the limits.
Lithium
Detected in 5 of 15 samples. Highest result 10.8 ppb. EPA's non-enforceable screening level is 10 ppb. Below screening level The screening level is how EPA decides what to study further, not a health limit. There is no federal limit for lithium and no filter is certified to remove it. About lithium.
Lead and copper
Latest 90th percentile: 3.6 ppb lead (Jan 2026 – Jun 2026). Below action level
Highest since 2016: 11 ppb (Dec 2019).
| Monitoring period | Lead (90th pct.) |
|---|---|
| Jan 2026 – Jun 2026 | 3.6 ppb |
| Jul 2025 – Dec 2025 | 3.1 ppb |
| Jan 2025 – Jun 2025 | 3.9 ppb |
Earlier results (9)
| Jul 2024 – Dec 2024 | 3.6 ppb |
| Jan 2024 – Jun 2024 | 4 ppb |
| Jul 2023 – Dec 2023 | 3.9 ppb |
| Jan 2023 – Jun 2023 | 3.5 ppb |
| Jul 2022 – Dec 2022 | 3.8 ppb |
| Jan 2022 – Jun 2022 | 3.9 ppb |
| Jul 2021 – Dec 2021 | 4.5 ppb |
| Jan 2021 – Jun 2021 | 4.1 ppb |
| Jul 2020 – Dec 2020 | 4.1 ppb |
Lead service lines: Denver Water Board's inventory lists 9,939 lead, 21,555 of unknown material out of 311,470 service lines (as of 2026-11-10). It reports 39,905 lead lines replaced. Counted by us from the utility's or state's published line-by-line inventory data.
Look up your address · Source (the utility, collected by us on Nov 14, 2026, not EPA data) · Checking your own line
Lead comes from pipes and fixtures, not the source water, so it varies home to home. The 90th percentile means 9 in 10 sampled homes were at or below it. More on lead.
Violations
Health-based violations mean a contaminant exceeded a limit or a required treatment step was missed. Monitoring and reporting violations mean required tests or reports were late or missing, so the water's quality during that time is unknown. The total includes every violation in EPA's records, most of them paperwork.
Earlier EPA testing (2013–2020)
| Contaminant | Highest | Guideline |
|---|---|---|
| Manganese | 26 ppb | 300 ppb |
| Molybdenum | 15 ppb | 40 ppb |
| Vanadium | 0.72 ppb | 21 ppb |
| Chromium-6 | 0.25 ppb | – |
| Strontium | 0.26 ppm | 1.5 ppm |
Where it serves
Denver
76 ZIP codes the system reported serving
80002, 80003, 80004, 80005, 80007, 80010, 80011, 80012, 80014, 80019, 80021, 80022, 80030, 80031, 80033, 80110, 80111, 80112, 80113, 80120, 80121, 80122, 80123, 80124, 80125, 80126, 80127, 80128, 80129, 80130, 80134, 80137, 80202, 80203, 80204, 80205, 80206, 80207, 80209, 80210, 80211, 80212, 80214, 80215, 80216, 80218, 80219, 80220, 80221, 80222, 80223, 80224, 80225, 80226, 80227, 80228, 80229, 80230, 80231, 80232, 80235, 80236, 80237, 80238, 80239, 80246, 80247, 80249, 80264, 80265, 80293, 80294, 80401, 80403, 80465, 80642
Nearby utilities
- City of Aurora Aurora · 9 mi
- East Cherry Creek Valley Water & Sanitation District Aurora · 9 mi
- South Adams County Water & Sanitation District Commerce City · 10 mi
- City of Englewood Englewood · 10 mi
- City of Thornton Thornton · 11 mi
- Todd Creek Village Metropolitan District Thornton · 11 mi · PFAS above limit
Questions
Is Denver tap water safe to drink?
Most of Denver gets its water from Denver Water Board. Denver Water Board has no health-based violations since 2016. EPA testing found no PFAS above the federal limits. Federal data can't tell you about your own pipes: lead comes from service lines and plumbing, so test your tap if your home was built before 1986. For the official word, read the utility's annual Consumer Confidence Report.
Does Denver water have PFAS?
EPA tested Denver Water Board for 29 PFAS between Mar 2023 and Apr 2025 and none were detected above the reporting limits (about 2 to 20 ppt depending on the chemical).
What is the lead level in Denver water?
The most recent 90th-percentile lead result for Denver Water Board is 3.6 ppb, for the period ending Jun 2026. The federal action level is 15 ppb, falling to 10 ppb in November 2027. The 90th percentile means 9 in 10 homes sampled were at or below this number. Individual homes can be higher.
Check these numbers yourself
Every figure on this page comes from public EPA records. You don't have to take our word for it:
- EPA's own report for CO0116001: violations, enforcement and inspections, straight from EPA.
- EPA UCMR 5 data: the PFAS and lithium results (search the file for PWSID CO0116001).
- EPA SDWIS download: the lead results, population and violation records we use.
- Denver Water Board's 2026 water quality report: the utility's own annual report, including contaminants EPA's national database doesn't carry (link checked Nov 14, 2026). Phone: (303) 994-6605.
- Denver Water Board website
Found something that doesn't match? Tell us and we'll check it against EPA's records. How we check our data.
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.