PlainWater
Counties → California

Tuolumne County, California

Water Systems
120
Population Served
82,529
Total Violations
1,665
383 health-based
PFAS Detected
3
of 5 tested

Violation Analysis

92.5%
Systems with Violations
13.9
Avg Violations per System
23.0%
Health-Based Violations

Water Source Types

GW
27 systems (23%)
SW
23 systems (19%)

PFAS Contamination

5
Systems Tested
3
PFAS Detected
60.0%
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

Tuolumne 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
Tud - Upper Basin Water System 13,280 2 Clean
Tud - Sonora/Jamestown Water System 11,054 14 Clean
Tud - Columbia Water System 5,463 2 Clean
Peppery Bar and Grill, The 4,500 4 -
Cdcr - Sierra Conservation Center 3,571 30 -
Groveland Community Serv Dist 3,400 18 Detected
Lake Don Pedro Csd 3,240 58 -
Yosemite Nps-Tuolumne Meadows 2,500 5 -
Twain Harte Community Services District 2,378 5 -
MI Wuk Village Mut Wtr Co 2,163 11 -
Cold Springs Water Co 1,771 3 -
Tud - Ponderosa 1,767 23 -
Tud - Tuolumne Water System 1,761 3 -
Pinecrest Permittees Assn 1,298 10 -
Del Oro Water Company - Strawberry Div. 1,295 50 -
Phoenix Lake Estates Cc MWC 1,168 47 -
Sonora Water Resources, Inc 1,154 5 -
Sonora Meadows Mutual Wtr Co 1,123 11 -
Don Pedro Rec Ag:flem.meadows 1,041 28 -
Usbr-Tuttletown Rec Area 1,000 6 -
Tud-Apple Valley Estates 826 4 -
Usfs Clark Fork Campd 612 1 -
Jenness Park Christian Camp 507 8 -
Camp Tawonga 505 1 -
Camp Mather 500 8 -
Belleview Oaks Mutual Water Co 468 6 -
MI Wuk Heights MWC 445 15 -
Slide Inn Snowbowl Water Co 417 10 -
Yosemite Lakes Campground 413 36 -
Sierra Park Water Company Inc. 400 16 -
Berkeley Tuolumne Camp 380 30 -
Usfs Baker/Deadman Cgd 366 2 -
Sierra Village Mutual Water Co 361 12 -
Usfs Fraser Flat Campgd 348 10 -
Leisure Pines Mutual Water Co 340 10 -
Dodge Ridge Ski Resort 328 7 -
Cascade Estates 316 24 -
Heavenly Hills Christian Camp 304 10 -
Usfs Sourgrass Campgd 300 4 -
Yosemite Nps-White Wolf 300 0 -
Don Pedro Rec Ag:blue Oaks 296 2 -
Sierra Outdoor School 289 30 -
Bluebell Valley MWC 282 20 -
Peppermint Creek MHP 280 27 -
Rawhide Mutual Water Company 269 11 -
Christian Berets Conf. Center 268 6 -
Sonora Estates Mobile Home Park 235 7 -
Foothill Horizons 230 24 -
San Jose Family Camp 230 12 -
Under Canvas-Yosemite 226 0 -

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 Tuolumne County? ▼
Tuolumne County has 1,665 total drinking water violations across 120 water systems, of which 383 are health-based violations. 92.5% of systems have at least one violation.
How many people get water from Tuolumne County systems? ▼
Water systems in Tuolumne County serve approximately 82,529 people through 120 public water systems.
Has PFAS been detected in Tuolumne County water? ▼
Of 5 water systems tested for PFAS in Tuolumne County, 3 had PFAS detected (60.0% detection rate).
What types of water sources supply Tuolumne County? ▼
Water systems in Tuolumne County use GW (27 systems), SW (23 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. 23.0% of Tuolumne 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.