PlainWater
Counties → Montana

Lewis and Clark County, Montana

Water Systems
162
Population Served
67,948
Total Violations
24,270
1,677 health-based
PFAS Detected
1
of 1 tested

Violation Analysis

96.3%
Systems with Violations
149.8
Avg Violations per System
6.9%
Health-Based Violations

Water Source Types

GW
47 systems (29%)
SW
3 systems (2%)

PFAS Contamination

1
Systems Tested
1
PFAS Detected
100.0%
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

Lewis and Clark Montana water systems by violation status, EPA SDWIS records.

No violations on record (0) One or more violations (50)

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
Helena Water System 32,091 68 Clean
East Helena City Of 2,114 44 -
Eastgate Village Sewer and Water 2,000 18 -
VA Medical Center Helena 1,275 39 -
Helena Leisure LLC 1,200 1,336 -
Bobs Valley Service Inc 1,032 78 -
Daves Express Lube 966 69 -
Mountain View Coop Lincoln 950 46 -
Dearborn N Craig Rest Stop 808 31 -
Big Sky Food and Fuel Inc 770 31 -
Ten Mile and Pleasant Valley Wua 750 460 -
North Star PUD 715 100 -
White Sandy Campground 600 26 -
Fort Harrison Military Complex 580 15 -
Jim Darcy School District No 1 575 183 -
Rossiter School District 01 550 175 -
T and T Subdivision 531 44 -
Our Lady of the Valley Catholic Church 502 19 -
Devils Elbow Rec Site 501 47 -
McHugh Mobile Home Park 490 85 -
Treasure State Acres Wua 483 40 -
Green Meadow Country Club 471 235 -
Grubstake Lounge and Restaurant 470 46 -
Anderson Stevenson Wilke Funeral Home 411 10 -
La Casa Grande Water and Sewer District 404 48 -
Skyview Water and Sewer Utility 400 69 -
Golden Estates Homeowners Association 400 357 -
Great Divide Ski Area 364 26 -
Holter Lake Rec Site Cg No 15 Blm 352 21 -
Warren School District No 1 350 321 -
Eastgate School District 09 342 95 -
Last Chance Chapel 313 154 -
Log Gulch Recreation Site Blm 306 58 -
Lincoln School District No 38 300 43 -
Kims Marina and Resort 300 136 -
Mobile City Home Park No 2 300 623 -
Holter Dam Cg Blm 300 25 -
Canyon Ferry Road Baptist Church 292 111 -
Gates of the Mountains Inc 251 97 -
Helena RV and Mobile Home Park 250 2,806 -
Ranchview Estates Wua 250 18 -
Clark's Bay Rec Site 250 39 -
Spring Meadow Lake State Park 250 35 -
Red Fox Supper Club 245 96 -
Grass Land Estates 228 65 -
Golden Estates Trailer Court 225 51 -
Holmberg Village Estates 225 164 -
Sun Canyon Lodge 210 54 -
Glacier Point Ho and Wua 210 58 -
Lazy I Public House, LLC Dba Lazy I Beer 205 172 -

Other Counties in Montana

Yellowstone County
116 systems · 168,956 served · 16,006 violations
Gallatin County
207 systems · 147,444 served · 30,683 violations
Missoula County
243 systems · 138,758 served · 31,553 violations
Flathead County
324 systems · 105,538 served · 20,270 violations
Cascade County
98 systems · 96,521 served · 15,613 violations
Silver Bow County
23 systems · 42,630 served · 2,525 violations

Drinking Water Guides

Frequently Asked Questions

How many water violations are in Lewis and Clark County? ▼
Lewis and Clark County has 24,270 total drinking water violations across 162 water systems, of which 1,677 are health-based violations. 96.3% of systems have at least one violation.
How many people get water from Lewis and Clark County systems? ▼
Water systems in Lewis and Clark County serve approximately 67,948 people through 162 public water systems.
Has PFAS been detected in Lewis and Clark County water? ▼
Of 1 water systems tested for PFAS in Lewis and Clark County, 1 had PFAS detected (100.0% detection rate).
What types of water sources supply Lewis and Clark County? ▼
Water systems in Lewis and Clark County use GW (47 systems), SW (3 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. 6.9% of Lewis and Clark 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.