COSTILLA COUNTY WS
PWS ID: CO0112300 · SAN LUIS, Colorado 81152
Population Served
561
Total Violations
116
Health-Based Violations
5
Water Source
Groundwater
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 396
- County
- Costilla
- School/Daycare
- No
- MCL Violations
- 4
- Monitoring Violations
- 110
- Treatment Tech Violations
- 1
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 9 | 2001 |
| Gross Alpha, Excl. Radon and U | MR | 8 | 2016 |
| Lead and Copper Rule | MR | 6 | 2006 |
| Nitrate | MR | 5 | 1993 |
| p-Dichlorobenzene | MR | 4 | 2016 |
| Trichloroethylene | MR | 4 | 2016 |
| Carbon tetrachloride | MR | 4 | 2016 |
| 1,2-Dichloroethane | MR | 4 | 2016 |
| 1,1-Dichloroethylene | MR | 4 | 2016 |
| 1,1,1-Trichloroethane | MR | 4 | 2016 |
| Benzene | MR | 4 | 2016 |
| Coliform (TCR) | MCL | 4 | 2002 |
| cis-1,2-Dichloroethylene | MR | 3 | 2016 |
| DICHLOROMETHANE | MR | 3 | 2016 |
| trans-1,2-Dichloroethylene | MR | 3 | 2016 |
| 1,1,2-Trichloroethane | MR | 3 | 2016 |
| CHLOROBENZENE | MR | 3 | 2016 |
| Ethylbenzene | MR | 3 | 2016 |
| Styrene | MR | 3 | 2016 |
| Combined Radium (-226 and -228) | MR | 3 | 2016 |
| TTHM | MR | 3 | 2022 |
| Total Haloacetic Acids (HAA5) | MR | 3 | 2022 |
| 1,2-Dichloropropane | MR | 3 | 2016 |
| Di(2-ethylhexyl) phthalate | MR | 3 | 2020 |
| Tetrachloroethylene | MR | 3 | 2016 |
| Vinyl chloride | MR | 3 | 2016 |
| o-Dichlorobenzene | MR | 3 | 2016 |
| Xylenes, Total | MR | 3 | 2016 |
| 1,2,4-Trichlorobenzene | MR | 3 | 2016 |
| Toluene | MR | 3 | 2016 |
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025.
This data is provided for informational purposes only.