Public water system · MT0000208
ActiveEnnis Town of
At a glance
Town of Ennis (PWSID MT0000208) is an active community water system in Madison County, Montana. It reports serving 1,400 people through 757 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 October 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,400
Service connections
757
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Town of Ennis compare with other water systems in Madison County?
By EPA's size categories, Town of Ennis is a small system (501 to 3,300 people). Madison County has 45 active public water systems, and Town of Ennis is the 3rd-largest of them by population served. Its population served is about 4.4 times the county average of 320 people per system, and accounts for 9.7% of the 14,392 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 Ennis 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 Town of Ennis?
EPA lists Town of Ennis 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. 7 of the 45 active systems in Madison County (16%) are also owned by a local government.
Does Town of Ennis have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2023. The violations listed here began between July 2018 and October 2023. By type: 12 monitoring and reporting. The contaminant or rule involved most often is Lead and Copper Rule (2 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 |
|---|---|---|---|---|
| 2023-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2020-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | 2,4-Dcode 2105 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Picloramcode 2040 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Atrazinecode 2050 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Heptachlor epoxidecode 2067 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlordanecode 2959 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Pentachlorophenolcode 2326 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Methoxychlorcode 2015 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dalaponcode 2031 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Hexachlorocyclopentadienecode 2042 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Benzo(a)pyrenecode 2306 | 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 Ennis: frequently asked questions
Who runs Town of Ennis?
Town of Ennis (PWSID MT0000208) 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 Ennis serve?
Town of Ennis reports serving 1,400 people through 757 service connections in Madison County, Montana.
Where does Town of Ennis 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 Ennis 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 October 2023. 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 Ennis' 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 October 2023. 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 Ennis' water quality report?
As a community water system, Town of Ennis 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 Madison County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Big Sky County Water and Sewer Dist 363 | Madison | 4,132 | Community | Groundwater |
| Virginia City Water Dept | Madison | 1,500 | Community | Groundwater |
| Sheridan Town of | Madison | 632 | Community | Groundwater |
| Nevada City | Madison | 621 | Transient non-community | Groundwater |
| Earthquake Lake Visitor Center | Madison | 503 | Transient non-community | Groundwater |
| Ennis S Raynolds Pass Rest Area | Madison | 500 | Transient non-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, “Ennis Town of, PWSID MT0000208, Montana”, https://aquacensus.com/water-systems/montana/ennis-town-of-mt0000208 (data as of October 1, 2026).