No PFAS were detected in any of the 15 samples EPA's program collected.
Denver Water Board is a public water system drawing on surface water, based in Denver, Colorado, serving about 1.3 million people, including Arvada, Aurora, Broomfield, Commerce City, Westminster, Wheat Ridge. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 15 times across 4 sampling points between Mar 2023 and Apr 2025.
None of the 29 PFAS were found at or above EPA's minimum reporting levels (2 to 20 ppt depending on the compound).
Not detected: PFPeS, PFMBA, PFNA, PFMPA, 8:2 FTS, 4:2 FTS, 6:2 FTS, PFBA, HFPO-DA, ADONA, 9Cl-PF3ONS, 11Cl-PF3OUdS, PFUnA, PFHxA, PFDoA, PFDA, PFBS, NMeFOSAA, NFDHA, PFEESA, PFPeA, PFTA, PFOA, NEtFOSAA, PFOS, PFHpA, PFHxS, PFHpS, PFTrDA.
Lithium, tested in the same program: highest 10.8 ppb, detected in 5 of 15 samples. EPA's health-based screening level is 10 ppb.
In April 2024 EPA set enforceable limits of 4 ppt for PFOA and PFOS, 10 ppt each for PFHxS, PFNA and GenX, and a hazard index of 1 for mixtures. Utilities were given until 2029 to comply. In May 2026 EPA proposed keeping only the PFOA and PFOS limits and moving that deadline to 2031. Until that proposal is final, the 2024 limits stand.
Compliance is judged on a running annual average at each entry point, so we show the average at this system's worst sampling point next to its single highest result. UCMR 5 results do not by themselves put a utility in or out of compliance.
No PFAS action is needed on these results. If your water tastes or smells of chlorine, a whole-house city water filter is the usual fix.
All 165 tested systems in Colorado
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
As reported by the utility to EPA. Neighbouring ZIPs are often split between systems; your water bill names yours.
Well & Tap. "PFAS in Denver Water Board water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID CO0116001. https://wellandtap.com/pfas/colorado/denver-water-board/
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID CO0116001). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
