PlainWater
Counties → California

Yolo County, California

Water Systems
90
Population Served
260,218
Total Violations
2,443
1,005 health-based
PFAS Detected
4
of 5 tested

Violation Analysis

92.2%
Systems with Violations
27.1
Avg Violations per System
41.1%
Health-Based Violations

Water Source Types

GW
45 systems (50%)
SW
5 systems (6%)

PFAS Contamination

5
Systems Tested
4
PFAS Detected
80.0%
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

Yolo 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
City of Davis 67,457 62 Clean
City of Woodland 61,462 4 Clean
City of West Sacramento 53,355 4 Clean
Uc - Davis 49,616 10 Clean
City of Winters 7,115 8 Detected
Esparto C.s.d. 3,574 13 -
Wild Wings Golf Community 1,115 14 -
Caltrans-Dunigan Rs 1,000 0 -
Pacific Coast Producers 1,000 13 -
Knights Landing Svc. Dist. 944 20 -
Madison Service Dist 876 53 -
Monroe/Leinberger Cntr - Waters 800 14 -
Cal Am - Dunnigan 602 36 -
St Joseph's Church 500 11 -
Clarksburg Middle School 460 24 -
Clark Pacific - Cr 18C 450 26 -
Yolo Co Housing Authority-El Rio Villa 432 14 -
Yolo Fliers Club 415 30 -
Plainfield Elem School - Water 400 8 -
North Davis Meadows 314 31 -
Crew Wine Company 312 12 -
Grace Valley Christian Center 304 0 -
Heringer Estates Winery 300 8 -
Jack in the Box #3465 300 20 -
Sacwest RV Park and Campground 300 17 -
Berryessa Brewing Company 300 11 -
First Baptist Church 300 13 -
Delta High School 250 5 -
Sacramento Yacht Club 250 20 -
Dollar General Store #16171 250 8 -
Unitarian Church of Davis 250 4 -
Jehovah's Witnesses - Kingdom Hall 245 25 -
Cacheville Service Dist 239 77 -
Canyon Creek Resort 212 6 -
Dunnigan Chevron 205 37 -
Americas Best Value Inn 200 20 -
Migrant Head Start Program - Water 200 48 -
United Travel Plaza 200 45 -
The Maples 200 6 -
Jehovah's Witnesses - Southport 200 2 -
Bayer Research and Development LLC 178 13 -
Clarksburg Comm Church 160 9 -
Zamora Shell & Mini Mart 158 59 -
Mariani Nut Company - Buckeye RD 150 10 -
Nelson's Grove 150 6 -
Campers Inn - RV & Golf Course 140 355 -
Road Trip Bar & Grill 120 17 -
Yolo Co Airport 114 13 -
Ihs Nor Cal Youth Trmnt Ctr(sacred Oaks) 104 1 -
Excel Gas and Market 100 72 -

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 Yolo County? ▼
Yolo County has 2,443 total drinking water violations across 90 water systems, of which 1,005 are health-based violations. 92.2% of systems have at least one violation.
How many people get water from Yolo County systems? ▼
Water systems in Yolo County serve approximately 260,218 people through 90 public water systems.
Has PFAS been detected in Yolo County water? ▼
Of 5 water systems tested for PFAS in Yolo County, 4 had PFAS detected (80.0% detection rate).
What types of water sources supply Yolo County? ▼
Water systems in Yolo County use GW (45 systems), SW (5 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. 41.1% of Yolo 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.