PlainWater
Counties → Montana

Big Horn County, Montana

Water Systems
23
Population Served
10,335
Total Violations
6,556
203 health-based
PFAS Detected
1
of 1 tested

Violation Analysis

95.7%
Systems with Violations
285.0
Avg Violations per System
3.1%
Health-Based Violations

Water Source Types

GW
15 systems (65%)
SW
8 systems (35%)

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

Big Horn Montana water systems by violation status, EPA SDWIS records.

No violations on record (1) One or more violations (22)

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
Hardin City Of 3,500 63 Clean
Little Bighorn Battlefield NM 2,020 42 -
Hardin Eastbound Rest Area 877 112 -
Hardin Westbound Rest Area 715 33 -
Lodge Grass Town Of 480 1,445 -
Fort Smith Water and Sewer District 450 830 -
Tongue River Campers Point 305 23 -
Tongue River Pee Wee Point 300 17 -
Chief Plenty Coups Museum 262 62 -
Big Horn Co Historical Museum 206 34 -
Spring Creek Mine 200 50 -
Spring Creek Coal Domestic 200 316 -
St Charles School 152 1,793 -
Yellowtail Dam Gc System 125 226 -
7th Ranch RV Camp 102 53 -
Hardin KOA Cistern 100 41 -
Cottonwood Camp Fort Smith 85 98 -
Absaloka Mine 80 347 -
Wegner Water Service Hauler 50 657 -
Yellowtail Dam Powerplant and Visitor Ce 48 73 -
East Decker Coal Mine 28 31 -
Kirby Saloon 25 210 -
Reese and Ray Iga Hardin 25 0 -

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
Lewis and Clark County
162 systems · 67,948 served · 24,270 violations

Drinking Water Guides

Frequently Asked Questions

How many water violations are in Big Horn County? ▼
Big Horn County has 6,556 total drinking water violations across 23 water systems, of which 203 are health-based violations. 95.7% of systems have at least one violation.
How many people get water from Big Horn County systems? ▼
Water systems in Big Horn County serve approximately 10,335 people through 23 public water systems.
Has PFAS been detected in Big Horn County water? ▼
Of 1 water systems tested for PFAS in Big Horn County, 1 had PFAS detected (100.0% detection rate).
What types of water sources supply Big Horn County? ▼
Water systems in Big Horn County use GW (15 systems), SW (8 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. 3.1% of Big Horn 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.