Public water system · MT0003623
ActiveWater Resources Division
At a glance
Water Resources Division (PWSID MT0003623) is an active non-transient non-community water system in Missoula County, Montana. It reports serving 60 people through 7 service connections. Its primary water source is groundwater, and EPA lists it as owned by a state government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in September 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
60
Service connections
7
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Water Resources Division compare with other water systems in Missoula County?
By EPA's size categories, Water Resources Division is a very small system (500 people or fewer). Missoula County has 244 active public water systems. Its population served is well below the county average of 576 people per system, and accounts for less than 0.1% of the 140,505 people reported by systems filed under the county. Across Montana, the 2,378 active systems average 489 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Water Resources Division is well below that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. Montana has 319 active non-transient non-community water systems, 13% 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 Water Resources Division?
EPA lists Water Resources Division as owned by a state 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. 18 of the 244 active systems in Missoula County (7.4%) are also owned by a state government.
Does Water Resources Division have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in September 2025. The violations listed here began between January 2023 and September 2025. By type: 11 monitoring and reporting and 1 monitoring. The contaminant or rule involved most often is Nitrate-Nitrite (2 of them). EPA lists 7 as archived, 4 as resolved and 1 as unaddressed. 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. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2025-09-18 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Unaddressed |
| 2025-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2024-11-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Endrincode 2005 | No | Archived |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Benzo(a)pyrenecode 2306 | No | Archived |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Toxaphenecode 2020 | No | Archived |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Lindane (gamma-BHC)code 2010 | No | Archived |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Oxamylcode 2036 | No | Archived |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Thalliumcode 1085 | No | Resolved |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 2,4,5-TP (Silvex)code 2110 | No | Archived |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Hexachlorobenzenecode 2274 | No | Archived |
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.
Water Resources Division: frequently asked questions
Who runs Water Resources Division?
Water Resources Division (PWSID MT0003623) is a non-transient non-community water system owned by a state government. It is regulated by the MT state drinking water program.
How many people does Water Resources Division serve?
Water Resources Division reports serving 60 people through 7 service connections in Missoula County, Montana.
Where does Water Resources Division 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 Water Resources Division 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 September 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 Water Resources Division'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 September 2025. For current results, consult EPA ECHO, or the MT state drinking water program.
Where can I find Water Resources Division's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Water Resources Division is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Missoula County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Missoula Water | Missoula | 68,200 | Community | Groundwater |
| University of Montana | Missoula | 15,000 | Non-transient non-community | Purchased groundwater |
| Lolo Water and Sewer Dist | Missoula | 3,315 | Community | Groundwater |
| Town Pump Bonner 1 | Missoula | 2,460 | Non-transient non-community | Groundwater |
| Clearwater Junction Rest Area | Missoula | 2,002 | Transient non-community | Groundwater |
| Seeley Lake Water District | Missoula | 1,575 | Community | Surface water |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Water Resources Division, PWSID MT0003623, Montana”, https://aquacensus.com/water-systems/montana/water-resources-division-mt0003623 (data as of October 1, 2026).