Public water system · MT0000187
ActiveCooke City Water District
At a glance
Cooke City Water District (PWSID MT0000187) is an active community water system in Park County, Montana. It reports serving 300 people through 98 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 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
300
Service connections
98
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Cooke City Water District compare with other water systems in Park County?
By EPA's size categories, Cooke City Water District is a very small system (500 people or fewer). Park County has 59 active public water systems. Its population served is about 11% above the county average of 271 people per system, and accounts for 1.9% of the 15,983 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 Cooke City Water District is well below 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 Cooke City Water District?
EPA lists Cooke City Water District 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. 5 of the 59 active systems in Park County (8.5%) are also owned by a local government.
Does Cooke City Water District 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 2025. The violations listed here began between April 2020 and July 2025. By type: 5 public notice, recordkeeping or other, 5 monitoring and reporting and 2 monitoring. The contaminant or rule involved most often is Consumer Confidence Rule (5 of them). EPA lists 12 as resolved. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2024-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2023-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2023-05-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2021-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) phthalatecode 2039 | No | Resolved |
| 2020-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) phthalatecode 2039 | No | Resolved |
| 2020-09-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2020-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2020-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Simazinecode 2037 | No | Resolved |
| 2020-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Picloramcode 2040 | No | Resolved |
| 2020-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Oxamylcode 2036 | 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.
Cooke City Water District: frequently asked questions
Who runs Cooke City Water District?
Cooke City Water District (PWSID MT0000187) is a community water system owned by a local government. It is regulated by the MT state drinking water program.
How many people does Cooke City Water District serve?
Cooke City Water District reports serving 300 people through 98 service connections in Park County, Montana.
Where does Cooke City Water District 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 Cooke City Water District 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 2025. 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 Cooke City Water District'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 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the MT state drinking water program.
Where can I find Cooke City Water District's water quality report?
As a community water system, Cooke City Water District 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 Park County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Livingston City of | Park | 7,500 | Community | Groundwater |
| Emigrant Rest Stop | Park | 800 | Transient non-community | Groundwater |
| Gardiner Park Co Water Dist | Park | 700 | Community | Groundwater |
| Sage Lodge | Park | 500 | Transient non-community | Groundwater |
| Yellowstone Travel Plaza Truck Stop | Park | 500 | Transient non-community | Groundwater |
| Chico Hot Springs | Park | 415 | Non-transient non-community | Surface water |
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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, “Cooke City Water District, PWSID MT0000187, Montana”, https://aquacensus.com/water-systems/montana/cooke-city-water-district-mt0000187 (data as of October 1, 2026).