San Jose, CA 95112
52 water systems • 2,072,724 residents
Excellent water quality with minimal contaminants
Score: 92/100
Graded on EPA violations, contaminants, severity, compliance, and enforcement history. See methodology.
Data updated June 2026 • Sources: EPA ECHO and EPA Envirofacts
21
Contaminants Detected
404
Violations on Record
195
Health-Based Violations
0
Recent Violations
Grade Breakdown
92 / 100 points
Recommended Water Filters
- ✓Point-of-Use Carbon Filter (NSF-certified for lead)
- ✓Reverse Osmosis or Ion Exchange Filter
- ✓Ultraviolet (UV) Purification
- ✓Activated Carbon Filter (disinfection byproducts)
Consult a water quality specialist for personalized recommendations.
San Jose vs CA & National Average
Detected Contaminants
21 contaminants detected across water systems serving this ZIP code
| Contaminant | Category |
|---|---|
| Nitrate | Agricultural |
| Simazine | Agricultural |
| Total Haloacetic Acids (HAA5) | Disinfection Byproduct |
| TTHM | Disinfection Byproduct |
| Arsenic | Heavy Metal |
| Lead and Copper Rule | Heavy Metal |
| Asbestos | Inorganic |
| Fluoride | Inorganic |
| Coliform (TCR) | Microorganism |
| E. COLI | Microorganism |
| Revised Total Coliform Rule | Microorganism |
| 1,2-DIBROMO-3-CHLOROPROPANE | Other |
| Endothall | Other |
| Epichlorohydrin | Other |
| Interim Enhanced Surface Water Treatment Rule | Other |
| Surface Water Treatment Rule | Other |
| Combined Radium (-226 and -228) | Radiological |
| Gross Alpha, Excl. Radon and U | Radiological |
| 1,1-Dichloroethylene | Volatile Organic |
| Benzene | Volatile Organic |
| Tetrachloroethylene | Volatile Organic |
Water System Information
- Systems Serving This ZIP:
- CAL-WATER SERVICE CO.-CHICO, CWS - MULLEN WATER COMPANY, CALIFORNIA WATER SERVICE - BEAR GULCH, CWSC LAS LOMAS, COMMERCE-CITY, WATER DEPT. +5 more
- Population Served:
- 2,072,724
- Systems With Violations:
- 46 of 52
- Major Violations:
- 39
- Enforcement Actions:
- 375
Frequently Asked Questions
What does the grade mean?
Our A–F grade ranks this ZIP code's water quality against every other analyzed ZIP in the country, based on EPA data. A = among the best, F = among the most troubled.
Is my tap water safe to drink?
Water systems regulated by the EPA must comply with Safe Drinking Water Act standards. However, if you're concerned about water quality, consider a water filter appropriate for your contaminants.
How often is the data updated?
We update our data quarterly with the latest EPA ECHO and Envirofacts data. Historical violations are tracked to identify patterns.
What filters do you recommend?
Filter recommendations are based on detected contaminants in your area. See our Filter Guide for detailed information about different filter types.