Water Quality in San Jose, CA: 7 Violations - Grade N/A
10 water systems · 28 directly mapped ZIP records
Available EPA records report 7 violations across 28 directly mapped ZIP records with known counts for San Jose. This is compliance evidence, not a property-level tap-water verdict.
Data: EPA Safe Drinking Water Information System (SDWIS)
Water Quality by ZIP Code in San Jose
This table shows typed EPA water evidence only. Missing violation counts are displayed as N/A, not zero.
| ZIP Code | Violations | Health | |
|---|---|---|---|
| 95112 | 3 | 1 | View report → |
| 95124 | 3 | 2 | View report → |
| 95127 | 3 | 2 | View report → |
| 95131 | 3 | 1 | View report → |
| 95134 | 3 | 1 | View report → |
| 95110 | 1 | 1 | View report → |
| 95111 | 1 | 1 | View report → |
| 95113 | 1 | 1 | View report → |
| 95116 | 1 | 1 | View report → |
| 95117 | 1 | 1 | View report → |
| 95118 | 1 | 1 | View report → |
| 95119 | 1 | 1 | View report → |
| 95120 | 1 | 1 | View report → |
| 95121 | 1 | 1 | View report → |
| 95122 | 1 | 1 | View report → |
Violation Trend
EPA violations recorded for water systems serving San Jose.
| Year | Total violations | Health-based |
|---|---|---|
| 2023 | 25 | 25 |
| 2024 | 2 | 2 |
Water Quality Overview
San Jose, California has directly mapped EPA water-system data for 28 ZIP codes. This page reports typed compliance facts and does not relabel the multi-source Home Safety Score as a drinking-water grade.
The available EPA records report 7 violations, including 3 health-based violations across 28 directly mapped ZIP records with reported counts.
Lead Levels
The average 90th percentile lead level across San Jose water systems is 0.0006 mg/L - within EPA limits. No exceedances appear among the 28 ZIP records with known lead status.
With 68% of homes built before 1986, San Jose has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Water Systems Serving San Jose
San Jose is served by 10 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 1,014,813 people across 57 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
The EPA has taken 59 enforcement actions against water systems serving San Jose. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in San Jose
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels and violation history
Request your CCR - your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test - certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration - NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories - monitor your local utility website and local news for boil water advisories or system alerts
Contaminants Detected in San Jose Water Systems
The following contaminants have been detected or caused violations across San Jose's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| E. coli | Microbiological | N/A | 25 | 25 | Yes |
| Stage 2 DBP Rule | Treatment Technique | N/A | 4 | 2 | Yes |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
Violation Trend Over Time
Year-by-year EPA violations recorded for water systems serving San Jose:
| Year | Total Violations | Health-Based |
|---|---|---|
| 2023 | 25 | 25 |
| 2024 | 2 | 2 |
Violations have decreased from 25 in 2023 to 2 in 2024, indicating improving compliance.
EPA Enforcement History
The EPA and state regulators have taken 5 enforcement actions against water systems serving San Jose. Recent actions:
| Date | Action Type |
|---|---|
| 2025-06-10 | State Filed Suit |
| 2023-08-16 | State Order Extension |
| 2023-06-13 | State Filed Suit |
| 2023-03-31 | State Order Extension |
| 2023-03-13 | State Filed Suit |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-06-10.
San Jose vs. Nearby California Cities
How San Jose's water quality compares to similar cities in California:
| City | Direct EPA ZIPs | Violations | Systems | Population |
|---|---|---|---|---|
| San Jose | 28 | 7 | 10 | 1,014,813 |
| Sacramento | 28 | 9 | 20 | 846,557 |
| San Francisco | 29 | 0 | 5 | 836,321 |
| San Diego | 40 | 1 | 9 | 1,330,316 |
Recommended Water Filters for San Jose
Based on contaminants detected in San Jose's water supply, these filter types are recommended:
Granular Activated Carbon (GAC, whole-house POE)
- Removes: Total Trihalomethanes
- Effectiveness: 80-99%
- Cost range: $400–$2000
- Certification: NSF/ANSI 53
- Recommended products:
Granular Activated Carbon (GAC, under-sink or whole-house)
- Removes: Haloacetic Acids
- Effectiveness: 60-80%
- Cost range: $100–$600
- Certification: NSF/ANSI 53
- Recommended products:
Water Quality by ZIP Code in San Jose
EPA coverage and recorded violations can differ across San Jose's ZIP codes. Missing counts are shown as unavailable, not zero:
| ZIP Code | Violations | Health-Based |
|---|---|---|
| 95112 | 3 | 1 |
| 95124 | 3 | 2 |
| 95127 | 3 | 2 |
| 95131 | 3 | 1 |
| 95134 | 3 | 1 |
| 95110 | 1 | 1 |
| 95111 | 1 | 1 |
| 95113 | 1 | 1 |
| 95116 | 1 | 1 |
| 95117 | 1 | 1 |
| 95118 | 1 | 1 |
| 95119 | 1 | 1 |
| 95120 | 1 | 1 |
| 95121 | 1 | 1 |
| 95122 | 1 | 1 |
Common Questions About San Jose Water
These are the most common questions residents search for about water quality in San Jose, California:
Is San Jose water hard or soft? Water hardness varies by source. San Jose's 10 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink San Jose tap water? City-level EPA records cannot determine safety at a specific tap. The measured subset contains 3 health-based violations; check the affected utility record and consider certified testing.
What is the best water filter for San Jose? Based on detected contaminants, a granular activated carbon (gac, whole-house poe) filter is most recommended. See our Water Filter Matcher for personalized recommendations.
San Jose vs. California Average
Understanding how San Jose compares to the broader California average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below - water quality can vary significantly even within San Jose.
ZIP Codes in San Jose
San Jose spans 57 ZIP codes. EPA water-system coverage is available for 28 directly mapped ZIP codes. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Source reporting periods vary. See each cited source for its publication schedule.