Public water system · MT0000515
ActiveMalmstrom Air Force Base
At a glance
Malmstrom Air Force Base (PWSID MT0000515) is an active community water system in Cascade County, Montana. It reports serving 8,850 people through 2 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by the federal government. Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in November 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
8,850
Service connections
2
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Malmstrom Air Force Base compare with other water systems in Cascade County?
By EPA's size categories, Malmstrom Air Force Base is a medium system (3,301 to 10,000 people). Cascade County has 98 active public water systems, and Malmstrom Air Force Base is the 2nd-largest of them by population served. Its population served is about 9 times the county average of 985 people per system, and accounts for 9.2% of the 96,513 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 Malmstrom Air Force Base is about 32% 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 212 Montana systems (8.9%) list purchased surface water as their primary source.
Who owns and regulates Malmstrom Air Force Base?
EPA lists Malmstrom Air Force Base as owned by the federal 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. 1 of the 98 active systems in Cascade County (1%) are also owned by the federal government.
Does Malmstrom Air Force Base have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in November 2024. The violations listed here began between July 2010 and November 2024. By type: 7 monitoring and reporting, 2 public notice, recordkeeping or other, 2 contaminant level above the legal limit and 1 monitoring. The contaminant or rule involved most often is Haloacetic acids (HAA5) (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 |
|---|---|---|---|---|
| 2024-11-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2024-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2023-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2021-12-30 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2020-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2020-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2019-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2018-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2017-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2017-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2010-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | 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.
Malmstrom Air Force Base: frequently asked questions
Who runs Malmstrom Air Force Base?
Malmstrom Air Force Base (PWSID MT0000515) is a community water system owned by the federal government. It is regulated by the MT state drinking water program.
How many people does Malmstrom Air Force Base serve?
Malmstrom Air Force Base reports serving 8,850 people through 2 service connections in Cascade County, Montana.
Where does Malmstrom Air Force Base get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Malmstrom Air Force Base have any drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in November 2024. 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 Malmstrom Air Force Base'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, 2 are health-based, and the most recent began in November 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the MT state drinking water program.
Where can I find Malmstrom Air Force Base's water quality report?
As a community water system, Malmstrom Air Force Base 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 Cascade County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Great Falls City of | Cascade | 60,000 | Community | Surface water |
| Source Giant Springs Inc. | Cascade | 3,007 | Non-transient non-community | Groundwater |
| Montana Expo Park Cascade County | Cascade | 2,510 | Transient non-community | Purchased surface water |
| Sun Prairie Village County | Cascade | 1,800 | Community | Groundwater |
| University of Providence | Cascade | 1,472 | Non-transient non-community | Purchased surface water |
| Black Eagle Cascade County Water Sewer | Cascade | 1,233 | Community | Purchased 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, “Malmstrom Air Force Base, PWSID MT0000515, Montana”, https://aquacensus.com/water-systems/montana/malmstrom-air-force-base-mt0000515 (data as of October 1, 2026).