HOWELL MOUNTAIN MUTUAL WATER COMPANY
PWS ID: CA2810001 · ANGWIN, California 94508
Population Served
1,240
Total Violations
92
Health-Based Violations
70
Water Source
Surface Water
System Details
- System Type
- Community
- Owner Type
- Private
- Connections
- 379
- County
- Napa
- School/Daycare
- No
- MCL Violations
- 66
- Monitoring Violations
- 21
- Treatment Tech Violations
- 4
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| TTHM | MCL | 40 | 2023 |
| Total Haloacetic Acids (HAA5) | MCL | 26 | 2011 |
| Surface Water Treatment Rule | MR | 8 | 2008 |
| TTHM | MR | 4 | 2009 |
| Surface Water Treatment Rule | TT | 4 | 1993 |
| Total Haloacetic Acids (HAA5) | MR | 4 | 2009 |
| Lead and Copper Rule | MR | 3 | 2020 |
| Nitrate | MR | 2 | 2015 |
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025.
This data is provided for informational purposes only.