DIAMOND A MUTUAL WATER COMPANY
PWS ID: CA4900562 · SONOMA, California 95476
Population Served
640
Total Violations
18
Health-Based Violations
3
Water Source
Groundwater
System Details
- System Type
- Community
- Owner Type
- Private
- Connections
- 194
- County
- Sonoma
- School/Daycare
- No
- MCL Violations
- 2
- Monitoring Violations
- 10
- Treatment Tech Violations
- 1
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 6 | 2002 |
| Nitrate | MR | 2 | 2006 |
| Coliform (TCR) | MCL | 2 | 2014 |
| Gross Alpha, Excl. Radon and U | MR | 2 | 1981 |
| LEAD AND COPPER RULE REVISIONS | TT | 1 | 2024 |
| LEAD AND COPPER RULE REVISIONS | RPT | 1 | 2024 |
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025.
This data is provided for informational purposes only.