Public water system · MT0004736
ActiveFort Harrison Military Complex
At a glance
Fort Harrison Military Complex (PWSID MT0004736) is an active non-transient non-community water system in Lewis and Clark County, Montana. It reports serving 580 people through 58 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by the federal government. EPA's records list 5 violations for this system; all are health-based, and the most recent began in December 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
580
Service connections
58
Primary source
SWP
Purchased surface water
System type
NTNCWS
Non-transient non-community water system
System record
How does Fort Harrison Military Complex compare with other water systems in Lewis and Clark County?
By EPA's size categories, Fort Harrison Military Complex is a small system (501 to 3,300 people). Lewis and Clark County has 165 active public water systems. Its population served is about 41% above the county average of 413 people per system, and accounts for 0.9% of the 68,071 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 Fort Harrison Military Complex is about 35% above 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. 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 Fort Harrison Military Complex?
EPA lists Fort Harrison Military Complex 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. 16 of the 165 active systems in Lewis and Clark County (9.7%) are also owned by the federal government.
Does Fort Harrison Military Complex have drinking water violations?
EPA's records list 5 violations for this system; all are health-based, and the most recent began in December 2024. The violations listed here began between April 2015 and December 2024. By type: 4 contaminant level above the legal limit and 1 required treatment not met. The contaminant or rule involved most often is Haloacetic acids (HAA5) (4 of them). EPA lists 5 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 |
|---|---|---|---|---|
| 2024-12-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 2023-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2022-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2022-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2015-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
All 5 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.
Fort Harrison Military Complex: frequently asked questions
Who runs Fort Harrison Military Complex?
Fort Harrison Military Complex (PWSID MT0004736) is a non-transient non-community water system owned by the federal government. It is regulated by the MT state drinking water program.
How many people does Fort Harrison Military Complex serve?
Fort Harrison Military Complex reports serving 580 people through 58 service connections in Lewis and Clark County, Montana.
Where does Fort Harrison Military Complex 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 Fort Harrison Military Complex have any drinking water violations?
EPA's records list 5 violations for this system; all are health-based, and the most recent began in December 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 Fort Harrison Military Complex'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. EPA's records list 5 violations for this system; all are health-based, and the most recent began in December 2024. For current results, consult EPA ECHO, or the MT state drinking water program.
Where can I find Fort Harrison Military Complex's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Fort Harrison Military Complex 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 Lewis and Clark County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Helena Water System | Lewis and Clark | 32,091 | Community | Surface water |
| East Helena City of | Lewis and Clark | 2,114 | Community | Groundwater |
| Eastgate Village Sewer and Water | Lewis and Clark | 2,000 | Community | Groundwater |
| Va Medical Center Helena | Lewis and Clark | 1,275 | Community | Purchased surface water |
| Helena Leisure LLC | Lewis and Clark | 1,200 | Community | Groundwater |
| Bobs Valley Service Inc. | Lewis and Clark | 1,032 | Non-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, “Fort Harrison Military Complex, PWSID MT0004736, Montana”, https://aquacensus.com/water-systems/montana/fort-harrison-military-complex-mt0004736 (data as of October 1, 2026).