CALIFORNIA WATER SERVICE-S SAN FRANCISCO
PWS ID: CA4110009 · SAN JOSE, California 95112
PFAS Detected
1 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.
Population Served
64,146
Total Violations
8
Health-Based Violations
3
Water Source
Surface Water
System Details
- System Type
- Community
- Owner Type
- Private
- Connections
- 16,449
- County
- San Mateo
- School/Daycare
- No
- MCL Violations
- 1
- Monitoring Violations
- 2
- Treatment Tech Violations
- 2
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Surface Water Treatment Rule | TT | 2 | 1993 |
| E. COLI | MR | 2 | 2013 |
| Coliform (TCR) | MCL | 1 | 1992 |
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 2 of 180 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFHxA | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| lithium | 9/18/2024 | <9 µg/L | 9 µg/L | Not Detected |
| NFDHA | 9/18/2024 | <0.02 µg/L | 0.02 µg/L | Not Detected |
| PFPeS | 9/18/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFMBA | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFPeA | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpS | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFBS | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpA | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHxS | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFNA | 9/18/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOS | 9/18/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOA | 9/18/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFTA | 9/18/2024 | <0.008 µg/L | 0.008 µg/L | Not Detected |
| PFBA | 9/18/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFEESA | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| NEtFOSAA | 9/18/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| NMeFOSAA | 9/18/2024 | <0.006 µg/L | 0.006 µg/L | Not Detected |
| PFMPA | 9/18/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| 8:2 FTS | 9/18/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFDA | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 6:2 FTS | 9/18/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFDoA | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| HFPO-DA | 9/18/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| ADONA | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 9Cl-PF3ONS | 9/18/2024 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| 11Cl-PF3OUdS | 9/18/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFUnA | 9/18/2024 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| PFTrDA | 9/18/2024 | <0.007 µg/L | 0.007 µg/L | Not Detected |
| 4:2 FTS | 9/18/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpA | 6/12/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFPeA | 6/12/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMPA | 6/12/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| 8:2 FTS | 6/12/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| NMeFOSAA | 6/12/2024 | <0.006 µg/L | 0.006 µg/L | Not Detected |
| NEtFOSAA | 6/12/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFTrDA | 6/12/2024 | <0.007 µg/L | 0.007 µg/L | Not Detected |
| PFTA | 6/12/2024 | <0.008 µg/L | 0.008 µg/L | Not Detected |
| PFHpS | 6/12/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFPeS | 6/12/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| NFDHA | 6/12/2024 | <0.02 µg/L | 0.02 µg/L | Not Detected |
| PFEESA | 6/12/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFOS | 6/12/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFHxS | 6/12/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMBA | 6/12/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFBS | 6/12/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 4:2 FTS | 6/12/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 6:2 FTS | 6/12/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFBA | 6/12/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| HFPO-DA | 6/12/2024 | <0.005 µg/L | 0.005 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.