YNP-MAMMOTH HOT SPRINGS
Wyoming — Community Water System — PWSID: WY5680092
System Information
| PWSID | WY5680092 |
| System Name | YNP-MAMMOTH HOT SPRINGS |
| System Type | Community Water System |
| Water Source | Surface Water |
| Activity Status | Active |
| Owner Type | Federal |
| EPA Region | 08 |
| Serves School | No |
| Wholesaler | No |
| First Reported | Feb 2, 1981 |
| Last Reported | Nov 17, 2025 |
Location & Contact
| State | Wyoming |
| City | YELLOWSTONE NATIONAL PARK |
| ZIP Code | 82190 |
| Address | P.O. Box 168 |
| Organization | JIMENO, MICHAEL |
| Phone | 307-344-2535 |
Population & Service
| Population Served | 2,600 |
| Service Connections | 274 |
Drinking Water Violations (12)
This water system has 12 violations recorded in the EPA SDWIS database.
| Begin Date | End Date | Contaminant | Category | Health-Based | Major | Measured | Federal MCL | State MCL | Status | Return to Compliance | Rule |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Aug 1, 2023 | Aug 31, 2023 | Surface Water Treatment Rule | MR | No | No | — | — | — | Resolved | Aug 31, 2023 | Surface Water Treatment Rule |
| Aug 1, 2023 | Aug 31, 2023 | Surface Water Treatment Rule | MR | No | No | — | — | — | Resolved | Aug 31, 2023 | Surface Water Treatment Rule |
| Jun 1, 2017 | May 31, 2018 | Total Haloacetic Acids (HAA5) | MR | No | Yes | — | 0.060 mg/L | — | Resolved | May 31, 2018 | Stage 2 Disinfectants and Disinfection Byproducts Rule |
| Jun 1, 2017 | May 31, 2018 | TTHM | MR | No | Yes | — | 0.080 mg/L | — | Resolved | May 31, 2018 | Stage 2 Disinfectants and Disinfection Byproducts Rule |
| Sep 1, 2013 | Sep 30, 2013 | Coliform (TCR) | MR | No | No | — | 5% of samples | — | Resolved | Sep 30, 2013 | Total Coliform Rule |
| Sep 1, 2013 | Sep 30, 2013 | Coliform (TCR) | MR | No | No | — | 5% of samples | — | Resolved | Sep 30, 2013 | Total Coliform Rule |
| Jul 1, 2005 | Jul 31, 2005 | Surface Water Treatment Rule | TT | Yes | No | — | — | — | Resolved | Jul 31, 2005 | Surface Water Treatment Rule |
| Jul 1, 2005 | Jul 31, 2005 | Surface Water Treatment Rule | TT | Yes | No | — | — | — | Resolved | Jul 31, 2005 | Surface Water Treatment Rule |
| Jan 1, 2005 | Mar 31, 2005 | CARBON, TOTAL | MR | No | Yes | — | TT | — | Resolved | Mar 31, 2005 | Stage 1 Disinfectants and Disinfection Byproducts Rule |
| Jan 1, 2005 | Mar 31, 2005 | CARBON, TOTAL | MR | No | Yes | — | TT | — | Resolved | Mar 31, 2005 | Stage 1 Disinfectants and Disinfection Byproducts Rule |
| Jun 24, 1980 | Jul 23, 1980 | Gross Alpha, Excl. Radon and U | MR | No | No | — | 15 pCi/L | — | Archived | Jul 23, 1980 | Radionuclides and Revised Rad Rule |
| Jun 24, 1980 | Jul 23, 1980 | Combined Radium (-226 and -228) | MR | No | No | — | 5 pCi/L | — | Archived | Jul 23, 1980 | Radionuclides and Revised Rad Rule |
About This Water System
Public water system data comes from the EPA Safe Drinking Water Information System (SDWIS). Systems with violations must notify customers. Contact your water utility for the latest annual water quality report.