LEWISTOWN CITY OF
PWS ID: MT0000271 · LEWISTOWN, Montana 59457
Population Served
5,923
Total Violations
512
Health-Based Violations
117
Water Source
Groundwater
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 2,906
- County
- Fergus
- School/Daycare
- No
- MCL Violations
- 117
- Monitoring Violations
- 386
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MCL | 117 | 2016 |
| Coliform (TCR) | MR | 14 | 2007 |
| Consumer Confidence Rule | Other | 9 | 2025 |
| Fluoride | MR | 8 | 2014 |
| Chromium | MR | 8 | 2014 |
| Cadmium | MR | 8 | 2014 |
| Barium | MR | 8 | 2014 |
| Selenium | MR | 8 | 2014 |
| Arsenic | MR | 8 | 2014 |
| Mercury | MR | 8 | 2014 |
| Antimony, Total | MR | 7 | 2014 |
| Thallium, Total | MR | 7 | 2014 |
| Nickel | MR | 7 | 2014 |
| Beryllium, Total | MR | 7 | 2014 |
| Endrin | MR | 6 | 2014 |
| BHC-GAMMA | MR | 6 | 2014 |
| Dalapon | MR | 6 | 2014 |
| OXAMYL | MR | 6 | 2014 |
| Picloram | MR | 6 | 2014 |
| Dinoseb | MR | 6 | 2014 |
| Carbofuran | MR | 6 | 2014 |
| Atrazine | MR | 6 | 2014 |
| LASSO | MR | 6 | 2014 |
| Heptachlor epoxide | MR | 6 | 2014 |
| 2,4-D | MR | 6 | 2014 |
| 2,4,5-TP | MR | 6 | 2014 |
| Benzo(a)pyrene | MR | 6 | 2014 |
| Pentachlorophenol | MR | 6 | 2014 |
| Chlordane | MR | 6 | 2014 |
| 1,2,4-Trichlorobenzene | MR | 6 | 2014 |
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 60 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| 9Cl-PF3ONS | 8/18/2025 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| NEtFOSAA | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| HFPO-DA | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFTA | 8/18/2025 | <0.008 µg/L | 0.008 µg/L | Not Detected |
| PFTrDA | 8/18/2025 | <0.007 µg/L | 0.007 µg/L | Not Detected |
| PFHpS | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFPeS | 8/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| NFDHA | 8/18/2025 | <0.02 µg/L | 0.02 µg/L | Not Detected |
| PFEESA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMBA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFPeA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMPA | 8/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| 8:2 FTS | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| 4:2 FTS | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFUnA | 8/18/2025 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| PFBA | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| lithium | 8/18/2025 | <9 µg/L | 9 µg/L | Not Detected |
| ADONA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 11Cl-PF3OUdS | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFHxA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFDoA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFDA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFOA | 8/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOS | 8/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFNA | 8/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFHxS | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFBS | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 6:2 FTS | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| NMeFOSAA | 8/18/2025 | <0.006 µg/L | 0.006 µg/L | Not Detected |
| PFPeA | 2/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 6:2 FTS | 2/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFBA | 2/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| 4:2 FTS | 2/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 8:2 FTS | 2/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFMPA | 2/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFMBA | 2/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFEESA | 2/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| NFDHA | 2/18/2025 | <0.02 µg/L | 0.02 µg/L | Not Detected |
| PFPeS | 2/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| NMeFOSAA | 2/18/2025 | <0.006 µg/L | 0.006 µg/L | Not Detected |
| PFTrDA | 2/18/2025 | <0.007 µg/L | 0.007 µg/L | Not Detected |
| PFHpS | 2/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFTA | 2/18/2025 | <0.008 µg/L | 0.008 µg/L | Not Detected |
| NEtFOSAA | 2/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFNA | 2/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| 9Cl-PF3ONS | 2/18/2025 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| ADONA | 2/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| lithium | 2/18/2025 | <9 µg/L | 9 µg/L | Not Detected |
| PFBS | 2/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025.
PFAS data from EPA UCMR5 monitoring program (2023-2025).
This data is provided for informational purposes only.