JOHNSTOWN TOWN OF
PWS ID: CO0162418 · JOHNSTOWN, Colorado 80534
Population Served
24,725
Total Violations
294
Health-Based Violations
21
Water Source
Surface Water
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 6,990
- County
- Weld
- School/Daycare
- No
- MCL Violations
- 0
- Monitoring Violations
- 254
- Treatment Tech Violations
- 21
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Interim Enhanced Surface Water Treatment Rule | MR | 43 | 2021 |
| Surface Water Treatment Rule | MR | 18 | 2022 |
| CARBON, TOTAL | TT | 13 | 2020 |
| CARBON, TOTAL | MR | 11 | 2017 |
| TTHM | MR | 11 | 2021 |
| Total Haloacetic Acids (HAA5) | MR | 11 | 2021 |
| Fluoride | MR | 10 | 2017 |
| Lead and Copper Rule | MR | 10 | 2019 |
| Nitrate | MR | 8 | 2017 |
| Surface Water Treatment Rule | TT | 8 | 2021 |
| Barium | MR | 6 | 2017 |
| Cadmium | MR | 6 | 2017 |
| Nickel | MR | 6 | 2017 |
| Thallium, Total | MR | 6 | 2017 |
| Selenium | MR | 6 | 2017 |
| Beryllium, Total | MR | 6 | 2017 |
| Mercury | MR | 6 | 2017 |
| Antimony, Total | MR | 6 | 2017 |
| Chromium | MR | 6 | 2017 |
| Arsenic | MR | 6 | 2017 |
| Revised Total Coliform Rule | Other | 4 | 2018 |
| cis-1,2-Dichloroethylene | MR | 3 | 2008 |
| Xylenes, Total | MR | 3 | 2008 |
| DICHLOROMETHANE | MR | 3 | 2008 |
| p-Dichlorobenzene | MR | 3 | 2008 |
| Vinyl chloride | MR | 3 | 2008 |
| 1,1-Dichloroethylene | MR | 3 | 2008 |
| trans-1,2-Dichloroethylene | MR | 3 | 2008 |
| 1,2-Dichloroethane | MR | 3 | 2008 |
| 1,1,1-Trichloroethane | MR | 3 | 2008 |
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 120 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFOA | 8/7/2023 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| ADONA | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 9Cl-PF3ONS | 8/7/2023 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| 11Cl-PF3OUdS | 8/7/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFUnA | 8/7/2023 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| PFHxA | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFDoA | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| HFPO-DA | 8/7/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFOS | 8/7/2023 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFBS | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFNA | 8/7/2023 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFHxS | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpA | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| NFDHA | 8/7/2023 | <0.02 µg/L | 0.02 µg/L | Not Detected |
| PFDA | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpS | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFBA | 8/7/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFPeS | 8/7/2023 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFEESA | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMBA | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFPeA | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMPA | 8/7/2023 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| 8:2 FTS | 8/7/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| 4:2 FTS | 8/7/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 6:2 FTS | 8/7/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFUnA | 8/22/2023 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| PFEESA | 8/22/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMBA | 8/22/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFPeA | 8/22/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMPA | 8/22/2023 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| 4:2 FTS | 8/22/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 6:2 FTS | 8/22/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFBA | 8/22/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFDA | 8/22/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 11Cl-PF3OUdS | 8/22/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| 9Cl-PF3ONS | 8/22/2023 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| PFOA | 8/22/2023 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| NFDHA | 8/22/2023 | <0.02 µg/L | 0.02 µg/L | Not Detected |
| PFDoA | 8/22/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| ADONA | 8/22/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| HFPO-DA | 8/22/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| 8:2 FTS | 8/22/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFHxA | 8/22/2023 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| NMeFOSAA | 8/22/2023 | <0.006 µg/L | 0.006 µg/L | Not Detected |
| NEtFOSAA | 8/22/2023 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFNA | 8/22/2023 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFTA | 8/22/2023 | <0.008 µg/L | 0.008 µg/L | Not Detected |
| PFPeS | 8/22/2023 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOS | 8/22/2023 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| lithium | 8/22/2023 | <9 µg/L | 9 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.