Results from entry points (water leaving treatment, not household taps) of public water systems sampled under EPA's Fifth Unregulated Contaminant Monitoring Rule. Click a county to see every water system serving it, or turn on service areas and click a location to see the systems that serve that spot.
34 of the 418 public water systems listed for Wyoming were sampled. Sorted by the highest single result relative to EPA's 2024 limits. Each name links to a page with all of that system's results. All 418 Wyoming systems, including those not tested · Download all Wyoming results (CSV, gzip)
| System | PWSID | City | Population | PFOA (ppt) | PFOS (ppt) | HI | Highest single result |
|---|---|---|---|---|---|---|---|
| Riverton, City Of | WY5600047 | Riverton | 10,330 | <MRL | 7 | 3.707 | Hazard Index ≥ 3 × its limit |
| Fort Washakie | 085690003 | Fort Washakie | 2,620 | 9.3 | <MRL | 0 | PFOA 1–3 × its limit |
| Jackson, Town Of | WY5600213 | Jackson | 24,760 | <MRL | <MRL | 0.33 | Hazard Index below its limit |
| Douglas, City Of | WY5600137 | Douglas | 6,400 | <MRL | <MRL | 0 | Other PFAS detected |
| Bar Nunn, Town Of | WY5600067 | Bar Nunn | 4,000 | <MRL | <MRL | 0 | No PFAS detected |
| Black Thunder Coal Mine | WY5600360 | Wright | 600 | <MRL | <MRL | 0 | No PFAS detected |
| Buffalo, City Of | WY5600005 | Buffalo | 4,419 | <MRL | <MRL | 0 | No PFAS detected |
| Casper, City Of | WY5601415 | Casper | 59,000 | <MRL | <MRL | 0 | No PFAS detected |
| Cheyenne Board Of Public Utilities | WY5600011 | Cheyenne | 64,165 | <MRL | <MRL | 0 | No PFAS detected |
| Cody, City Of | WY5600207 | Cody | 10,224 | <MRL | <MRL | 0 | No PFAS detected |
| Evanston, City Of | WY5600150 | Evanston | 11,727 | <MRL | <MRL | 0 | No PFAS detected |
| First Fike Subdivision | WY5600194 | Pavillion | 150 | <MRL | <MRL | 0 | No PFAS detected |
| Gillette, City Of | WY5600019 | Gillette | 32,222 | <MRL | <MRL | 0 | No PFAS detected |
| Green River, City Of | WY5601181 | Green River | 10,500 | <MRL | <MRL | 0 | No PFAS detected |
| Gtnp-Colter Bay Village | WY5680095 | Moose | 4,514 | <MRL | <MRL | 0 | No PFAS detected |
| High Meadow Ranch | WY5601569 | Pinedale | 622 | <MRL | <MRL | 0 | No PFAS detected |
| Kemmerer-Diamondville Jpb | WY5600028 | Kemmerer | 3,348 | <MRL | <MRL | 0 | No PFAS detected |
| Lander, City Of | WY5600176 | Lander | 7,615 | <MRL | <MRL | 0 | No PFAS detected |
| Laramie, City Of | WY5600029 | Laramie | 32,395 | <MRL | <MRL | 0 | No PFAS detected |
| Lovell, Town Of | WY5600031 | Lovell | 2,250 | <MRL | <MRL | 0 | No PFAS detected |
| Mills, City Of | WY5600036 | Mills | 4,050 | <MRL | <MRL | 0 | No PFAS detected |
| Newcastle, City Of | WY5600256 | Newcastle | 3,595 | <MRL | <MRL | 0 | No PFAS detected |
| Northwest Rural Water District | WY5601254 | Cody | 7,330 | <MRL | <MRL | 0 | No PFAS detected |
| Powell, City Of | WY5600042 | Powell | 6,310 | <MRL | <MRL | 0 | No PFAS detected |
| Rawlins Water Supply, City Of | WY5600045 | Rawlins | 9,006 | <MRL | <MRL | 0 | No PFAS detected |
| Rock Springs, City Of | WY5601182 | Rock Springs | 24,000 | <MRL | <MRL | 0 | No PFAS detected |
| Sheridan, City Of | WY5600052 | Sheridan | 22,700 | <MRL | <MRL | 0 | No PFAS detected |
| South Cheyenne Water & Sewer District | WY5600239 | Cheyenne | 10,000 | <MRL | <MRL | 0 | No PFAS detected |
| Torrington Municipal Water Dept, City Of | WY5600164 | Torrington | 6,847 | <MRL | <MRL | 0 | No PFAS detected |
| Usaf F.E. Warren Afb | WY5680122 | F.E. Warren Afb | 5,500 | <MRL | <MRL | 0 | No PFAS detected |
| Wheatland, Town Of | WY5600187 | Wheatland | 3,659 | <MRL | <MRL | 0 | No PFAS detected |
| Worland Utilities Commission | WY5600197 | Worland | 4,787 | <MRL | <MRL | 0 | No PFAS detected |
| Ynp-Canyon Village | WY5680074 | Yellowstone | 4,300 | <MRL | <MRL | 0 | No PFAS detected |
| Ynp-Old Faithful | WY5680085 | Yellowstone | 7,745 | <MRL | <MRL | 0 | No PFAS detected |
Highest single result for each system; PFOA and PFOS in ppt (ng/L). Entry-point samples, not tap water; screening comparisons, not compliance determinations.