PlainWater
Counties → Washington

Snohomish County, Washington

Water Systems
170
Population Served
947,238
Total Violations
8,193
553 health-based
PFAS Detected
2
of 19 tested

Violation Analysis

97.6%
Systems with Violations
48.2
Avg Violations per System
6.7%
Health-Based Violations

Water Source Types

SW
27 systems (16%)
GW
23 systems (14%)

PFAS Contamination

19
Systems Tested
2
PFAS Detected
10.5%
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

Snohomish Washington water systems by violation status, EPA SDWIS records.

No violations on record (1) One or more violations (49)

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
Everett Public Works Dept. City Of 215,774 5 Clean
Alderwood Water District 200,000 6 Clean
Marysville Utilities 88,589 21 Clean
Lynnwood City Of 68,204 8 Clean
Sno PUD 1 - Lake Stevens 60,064 25 Clean
Silver Lake Water & Sewer District 56,582 17 Clean
Edmonds City Of 34,023 0 Clean
Mountlake Terrace City Of 26,402 12 Clean
Mukilteo Water & Wastewater Distr 25,182 4 Clean
Monroe Water System 23,467 27 Clean
Cross Valley Water District 23,054 33 Detected
Arlington City Of 20,418 1 Detected
Olympic View Water & Sewer District 16,403 14 Clean
Stanwood Water Dept City Of 13,785 179 Clean
Snohomish City Of 11,258 111 Clean
Sultan Water Department 7,160 92 Clean
Granite Falls City Of 6,926 6 Clean
Seven Lakes Water Association 5,823 58 Clean
Roosevelt Water Association 3,493 17 -
Highland Water District 3,121 5 -
Sno PUD 1 - Warm Beach 2,890 19 -
Gold Bar City Of 2,745 85 Clean
Darrington Town of 2,246 44 -
Three Lakes Water Association 2,198 6 -
Sno PUD 1 - May Creek 1,364 4 -
Warm Beach Conference Grounds 1,190 46 -
Kayak Point County Park 978 9 -
Whitehorse Mercantile Water System 930 22 -
Sno PUD 1 - Storm Lake Ridge 786 29 -
Wallace Falls State Park 759 4 -
Wilderness Ridge Community Club 664 50 -
Startup Water District 643 26 -
Priest Point Beach Water Inc 624 63 -
Rivershore Water District #1 572 17 -
Sno PUD 1 - Sunday Lake 561 30 -
Zekes Drive-IN 502 5 -
Lake Alyson 463 13 -
Wilkshire Lane Water District Inc 460 6 -
Wandering Creek Homeowners Assoc 457 5 -
Thunderbird Park 454 94 -
Craven Farm Water System 431 9 -
Index Water Dept 420 130 -
Big Bend Landowners Association 419 194 -
Sno PUD 1 - Skylite Tracts 415 23 -
Tatoosh Water Company 387 34 -
Hat Island Community Inc 348 327 -
Sultan Estates Water System 340 10 -
Kackman Creek 330 34 -
Machias Ridge Homeowners Assoc. 324 10 -
Cedar Springs Camp 308 47 -

Other Counties in Washington

King County
217 systems · 3,193,095 served · 20,636 violations
Pierce County
359 systems · 1,138,508 served · 14,826 violations
Spokane County
164 systems · 621,798 served · 9,829 violations
Clark County
72 systems · 615,931 served · 9,864 violations
Thurston County
322 systems · 395,780 served · 24,330 violations
Kitsap County
221 systems · 331,366 served · 12,667 violations

Drinking Water Guides

Frequently Asked Questions

How many water violations are in Snohomish County? ▼
Snohomish County has 8,193 total drinking water violations across 170 water systems, of which 553 are health-based violations. 97.6% of systems have at least one violation.
How many people get water from Snohomish County systems? ▼
Water systems in Snohomish County serve approximately 947,238 people through 170 public water systems.
Has PFAS been detected in Snohomish County water? ▼
Of 19 water systems tested for PFAS in Snohomish County, 2 had PFAS detected (10.5% detection rate).
What types of water sources supply Snohomish County? ▼
Water systems in Snohomish County use SW (27 systems), GW (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. 6.7% of Snohomish 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.