F0/100
WEST YELLOWSTONE TOWN OF — Water Quality Report 2026
Serving 9,899 people · Montana
Water Source
Groundwater
County
—
System ID
MT0003136
Violations
89
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | 0.001 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
1
Violation (last 5yr)
1
Unresolved
0
Health-Related
TIER 3Unresolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: July 1, 2021 – September 30, 2021Verify on EPA.gov
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Frequently Asked Questions About WEST YELLOWSTONE TOWN OF
Is WEST YELLOWSTONE TOWN OF water safe to drink?
WEST YELLOWSTONE TOWN OF water receives a grade of F (0/100), which is considered failing. 0 contaminant(s) exceed EPA legal limits and 89 violation(s) are on record. Customers may want to consider using a water filter.
What contaminants has WEST YELLOWSTONE TOWN OF detected?
31 contaminants were tested in WEST YELLOWSTONE TOWN OF's water. Notable contaminants include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 exceed EPA health goals (MCLGs).
Does WEST YELLOWSTONE TOWN OF have any EPA violations?
Yes, WEST YELLOWSTONE TOWN OF has 89 EPA violation(s) on record, with the most recent in 2021. Violation types include MR, Other, TT. 2 are health-based violations.
How many people does WEST YELLOWSTONE TOWN OF serve?
WEST YELLOWSTONE TOWN OF serves approximately 9,899 people, Montana. The system provides water to 1 community: West Yellowstone.
What type of water does WEST YELLOWSTONE TOWN OF provide?
WEST YELLOWSTONE TOWN OF sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is MT0003136.
How does WEST YELLOWSTONE TOWN OF compare to other utilities in Montana?
WEST YELLOWSTONE TOWN OF scores 0/100 with a grade of F (failing). This score suggests significant water quality concerns relative to other utilities. Visit our Montana state page for a full comparison of water systems.