Public water system · MT0003136
ActiveWest Yellowstone Town of
At a glance
Town of West Yellowstone (PWSID MT0003136) is an active community water system in Gallatin County, Montana. It reports serving 9,899 people through 628 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2021.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
9,899
Service connections
628
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Town of West Yellowstone compare with other water systems in Gallatin County?
By EPA's size categories, Town of West Yellowstone is a medium system (3,301 to 10,000 people). Gallatin County has 207 active public water systems, and Town of West Yellowstone is the 4th-largest of them by population served. Its population served is about 14 times the county average of 713 people per system, and accounts for 6.7% of the 147,534 people reported by systems filed under the county. Across Montana, the 2,378 active systems average 489 people each. Nationally, the average active community water system reports serving 6,703 people, so Town of West Yellowstone is about 48% above that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. Montana has 853 active community water systems, 36% of the state's 2,378 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,994 Montana systems (84%) list groundwater as their primary source.
Who owns and regulates Town of West Yellowstone?
EPA lists Town of West Yellowstone as owned by a local government. The MT state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 12 of the 207 active systems in Gallatin County (5.8%) are also owned by a local government.
Does Town of West Yellowstone have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2021. The violations listed here began between July 2017 and July 2021. By type: 11 monitoring and reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Fluoride (3 of them). EPA lists 11 as resolved and 1 as archived. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2021-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Fluoridecode 1025 | No | Archived |
| 2021-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 2019-08-28 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2018-04-01 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2018-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Fluoridecode 1025 | No | Resolved |
| 2018-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Fluoridecode 1025 | No | Resolved |
| 2018-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 2017-12-07 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2017-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 2017-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Alachlor (Lasso)code 2051 | No | Resolved |
| 2017-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2017-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Endrincode 2005 | No | Resolved |
The 12 most recent violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Town of West Yellowstone: frequently asked questions
Who runs Town of West Yellowstone?
Town of West Yellowstone (PWSID MT0003136) is a community water system owned by a local government. It is regulated by the MT state drinking water program.
How many people does Town of West Yellowstone serve?
Town of West Yellowstone reports serving 9,899 people through 628 service connections in Gallatin County, Montana.
Where does Town of West Yellowstone get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Town of West Yellowstone have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2021. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Town of West Yellowstone's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2021. For current results, consult the system's annual water quality report, EPA ECHO, or the MT state drinking water program.
Where can I find Town of West Yellowstone's water quality report?
As a community water system, Town of West Yellowstone must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Gallatin County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Bozeman City of | Gallatin | 56,000 | Community | Surface water |
| Montana State University Bozeman | Gallatin | 19,200 | Non-transient non-community | Purchased surface water |
| Belgrade City of | Gallatin | 10,460 | Community | Groundwater |
| North Star Zoot Water | Gallatin | 4,323 | Community | Groundwater |
| River Rock County Water and Sewer Dist | Gallatin | 4,200 | Community | Groundwater |
| Rae Water and Sewer Dist 313 | Gallatin | 2,325 | Community | Groundwater |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “West Yellowstone Town of, PWSID MT0003136, Montana”, https://aquacensus.com/water-systems/montana/west-yellowstone-town-of-mt0003136 (data as of October 1, 2026).