States › California › Santa Clara County

Santa Clara County, CA Water Quality

Water quality data for 3 public water systems serving Santa Clara County, California — based on EPA SDWIS enforcement records, lead testing results, and health-based violation history.

📅 2026 Report 🔄 Data updated 2026 Q2 📍 3 water systems · 24 cities
✅
Excellent — All Systems Performing Well

Water quality across the county is outstanding with minimal violations and very low lead levels.

A

Santa Clara County Earns a A

Santa Clara County: 24 communities across 3 water systems. 100.0% have no open violations.

  • Median lead where detected: 2.00 ppb
  • 1 communities with a lead detection, 6 reporting none detected
  • 1 communities with PFAS above the federal limit
  • 0 with significant inspection deficiencies
  • 100.0% of communities have no open violations
2 ppb
Median Lead Level
County-wide, 90th percentile
3
Water Systems
Active CWS & NTNCWS
100%
Violation-Free
No active violations on record
How we grade counties: MyWaterIQ uses EPA SDWIS enforcement data — actual MCL violations and lead test results — not the aspirational MCLG targets used by some sites. A grade reflects real compliance history, not theoretical risk. Learn more →

Cities by Water Quality

⭐ Best Performing
  • San Jose
    Not reported
    No federal limits exceeded on record
    B
  • Sunnyvale
    Not reported
    No federal limits exceeded on record
    B
  • Santa Clara
    Not reported
    No federal limits exceeded on record
    B
  • Mountain View
    Not reported
    No federal limits exceeded on record
    B
  • Milpitas
    Not reported
    No federal limits exceeded on record
    B
⚠ Needs Attention
  • Gilroy
    2.00 ppb
    PFAS above the limit at 2 of 7 sampling points
    C
  • Campbell
    Not detected
    1 health-based violation since 2015
    A
  • Alum Rock
    Not detected
    1 health-based violation since 2015
    A
  • Burbank
    Not detected
    1 health-based violation since 2015
    A
  • Cambrian Park
    Not detected
    1 health-based violation since 2015
    A
County Lead Level — Median 2 ppb
Based on most recent 90th percentile lead tests across all reporting systems
0 ppb5 ppb10 ppb15 ppb
County median: 2 ppb — 13.3% of the federal action level
Systems by Lead Level
Under 5 ppb
1
No Data
23

All Cities in Santa Clara County

San Jose Not reported B
Sunnyvale Not reported B
Santa Clara Not reported B
Mountain View Not reported B
Milpitas Not reported B
Palo Alto Not reported B
Cupertino Not reported B
Gilroy 2.00 ppb C
Campbell Not detected A
Morgan Hill Not reported B
Los Gatos Not reported B
Los Altos Not reported B
Saratoga Not reported B
Stanford Not reported B
Alum Rock Not detected A
San Martin Not reported B
Los Altos Hills Not reported B
East Foothills Not reported B
Burbank Not detected A
Lexington Hills Not reported B
Cambrian Park Not detected A
Loyola Not reported B
Monte Sereno Not detected A
Fruitdale Not detected A
Showing 24 cities
No active violations Active violations

About Santa Clara County Drinking Water

Santa Clara County is served by 3 water systems covering 24 communities. No community here has an open violation on record.

Of the communities reporting lead results, 1 recorded a detection, with a median of 2.00 ppb — 13% of the federal action level. 6 reported none detected, which means below the laboratory limit rather than an absence of lead.

1 of 24 communities have PFAS above the limits EPA set in 2024, measured as a running annual average at each sampling point. State inspectors recorded no significant deficiencies.

Frequently Asked Questions

Is Santa Clara County tap water safe to drink?▼
No community in Santa Clara County has an open violation on record. 1 of 24 have PFAS above the federal limit, which is the main open concern.
What is the lead level in Santa Clara County?▼
Among communities with a detection the median is 2.00 ppb, 13% of the 15 ppb action level. 6 reported none detected and 17 reported no result.
How many water systems serve Santa Clara County?▼
3 community water systems serve 24 communities here.
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