PlainWater
Counties → California

Santa Clara County, California

Water Systems
119
Population Served
2,097,044
Total Violations
2,640
936 health-based
PFAS Detected
10
of 17 tested

Violation Analysis

91.6%
Systems with Violations
22.2
Avg Violations per System
35.5%
Health-Based Violations

Water Source Types

GW
26 systems (22%)
SW
24 systems (20%)

PFAS Contamination

17
Systems Tested
10
PFAS Detected
58.8%
Detection Rate

PFAS (per- and polyfluoroalkyl substances) are persistent chemicals found in drinking water. The EPA has set enforceable limits for several PFAS compounds under UCMR5 monitoring.

Compliance Snapshot

Santa Clara California water systems by violation status, EPA SDWIS records.

No violations on record (2) One or more violations (48)

Violation history is cumulative, many flagged systems have already returned to compliance. Detail pages show per-system context.

Water Systems

System Name Population Violations PFAS
San Jose Water 1,039,920 14 Detected
City of Sunnyvale 157,566 145 Clean
City of Santa Clara 130,746 7 Clean
Great Oaks WC Inc 110,088 11 Detected
City of San Jose - Evg/Edv/Coy 101,265 6 Clean
City of Milpitas 81,773 15 Clean
City of Mountain View 81,501 17 Clean
Cwsc los Altos Suburban 69,973 7 Detected
City of Palo Alto 67,231 18 Clean
City of Gilroy 59,203 2 Detected
City of Morgan Hill 47,374 256 Detected
City of San Jose - Nsj/Alviso 45,559 10 Clean
Stanford University 35,853 8 Clean
City of Cupertino 16,336 15 Clean
Nasa Ames Research Center 16,273 4 Clean
Purissima Hills Water District 6,245 17 Clean
El Camino Hospital 3,000 5 -
Santa Clara Valley Medical Center 3,000 21 -
O'Connor Hospital 2,500 31 -
Western Digital Technologies, Inc. 2,439 15 Clean
Cal Am - West San Martin 1,173 27 -
Gavilan Joint Community College District 989 11 -
Csp Henry W. Coe State Park 898 14 -
Christopher Ranch L.L.C. 735 9 -
San Martin County Water District 627 70 -
Mt. Madonna County Park 621 1 -
Loma Prieta Jusd-Loma Prieta School 542 15 -
Gilroy Usd-Rucker School 536 9 -
Uvas Canyon County Park 509 24 -
Coyote Valley RV Resort 500 4 -
Camp Saratoga 450 5 -
Cinnabar Hills Golf Club 450 10 -
Sanborn-Skyline County Park 414 28 -
Thousand Trails - Morgan Hill 413 8 -
Monterey Mushrooms 361 21 -
Chemeketa Park Mutual Water Company 346 67 -
Aldercroft Heights County Water District 338 57 -
Joseph Grant County Park 326 11 -
Twin Valley Inc 317 129 -
New Avenue Mutual Water Company 305 7 -
Mt. Pleasant Water Users Association 300 30 -
Lupin Lodge 300 57 -
Lick Observatory-Ucsc 284 6 -
Walden West 273 30 -
Willow Heights Mansion 269 0 -
Nestldown Ranch 265 0 -
Saratoga Heights Mutual Water Company 258 16 -
Casa de Fruta Water System 250 14 -
Parkway Lakes RV Park 250 19 -
George Chiala Farms Inc 250 30 -

Other Counties in California

Los Angeles County
276 systems · 10,109,089 served · 3,972 violations
San Diego County
197 systems · 3,744,323 served · 4,832 violations
Orange County
46 systems · 3,201,893 served · 507 violations
Riverside County
201 systems · 2,839,125 served · 6,103 violations
San Bernardino County
318 systems · 2,830,626 served · 4,611 violations
Alameda County
27 systems · 2,249,634 served · 275 violations

Drinking Water Guides

Frequently Asked Questions

How many water violations are in Santa Clara County? ▼
Santa Clara County has 2,640 total drinking water violations across 119 water systems, of which 936 are health-based violations. 91.6% of systems have at least one violation.
How many people get water from Santa Clara County systems? ▼
Water systems in Santa Clara County serve approximately 2,097,044 people through 119 public water systems.
Has PFAS been detected in Santa Clara County water? ▼
Of 17 water systems tested for PFAS in Santa Clara County, 10 had PFAS detected (58.8% detection rate).
What types of water sources supply Santa Clara County? ▼
Water systems in Santa Clara County use GW (26 systems), SW (24 systems) as their primary water sources.
Are health-based violations serious? ▼
Health-based violations indicate that drinking water exceeded Maximum Contaminant Levels (MCLs) set by the EPA or failed treatment technique requirements. 35.5% of Santa Clara County's violations are health-based. Not all violations indicate immediate health risk, but they require corrective action.
Data Sources & Methodology

Drinking water violation data from the EPA Safe Drinking Water Information System (SDWIS). PFAS testing data from the UCMR5 monitoring program. SDWIS tracks all public water systems regulated under the Safe Drinking Water Act.

Violations are categorized as health-based (Maximum Contaminant Level exceedances, treatment technique failures) or monitoring/reporting violations. Not all violations indicate an immediate health risk.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This page draws directly on EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.