Public water system · MT0003971
ActiveBig Valley Water Inc.
At a glance
Big Valley Water Inc. (PWSID MT0003971) is an active non-transient non-community water system in Valley County, Montana. It reports serving 200 people through 1 service connection. Its primary water source is purchased surface water, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in August 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
200
Service connections
1
Primary source
SWP
Purchased surface water
System type
NTNCWS
Non-transient non-community water system
System record
How does Big Valley Water Inc. compare with other water systems in Valley County?
By EPA's size categories, Big Valley Water Inc. is a very small system (500 people or fewer). Valley County has 13 active public water systems. Its population served is about 57% below the county average of 466 people per system, and accounts for 3.3% of the 6,060 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 Big Valley Water Inc. is about half of 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 Big Valley Water Inc.?
EPA lists Big Valley Water Inc. as privately owned. 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. 4 of the 13 active systems in Valley County (31%) are also privately owned.
Does Big Valley Water Inc. have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in August 2025. The violations listed here began between September 2017 and August 2025. By type: 7 monitoring and reporting and 5 monitoring. The contaminant or rule involved most often is Bromate (6 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 |
|---|---|---|---|---|
| 2025-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-12-30 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2023-06-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2023-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Bromatecode 1011 | No | Resolved |
| 2022-12-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Bromatecode 1011 | No | Resolved |
| 2021-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Bromatecode 1011 | No | Resolved |
| 2019-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Bromatecode 1011 | No | Resolved |
| 2019-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Bromatecode 1011 | No | Resolved |
| 2018-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Bromatecode 1011 | No | Resolved |
| 2018-03-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-09-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | 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.
Big Valley Water Inc.: frequently asked questions
Who runs Big Valley Water Inc.?
Big Valley Water Inc. (PWSID MT0003971) is a non-transient non-community water system privately owned. It is regulated by the MT state drinking water program.
How many people does Big Valley Water Inc. serve?
Big Valley Water Inc. reports serving 200 people through 1 service connection in Valley County, Montana.
Where does Big Valley Water Inc. 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 Big Valley Water Inc. 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 August 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 Big Valley Water Inc.'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 August 2025. For current results, consult EPA ECHO, or the MT state drinking water program.
Where can I find Big Valley Water Inc.'s water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Big Valley Water Inc. 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 Valley County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Glasgow City of | Valley | 3,253 | Community | Surface water |
| Fort Peck Rural County Water District | Valley | 663 | Community | Purchased surface water |
| North Valley County Water and Sewer Dist | Valley | 450 | Community | Purchased surface water |
| Nashua Town of | Valley | 300 | Community | Purchased surface water |
| Hinsdale Water Department | Valley | 250 | Community | Groundwater |
| Vandalia Glasgow West Rest Area | Valley | 250 | 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, “Big Valley Water Inc., PWSID MT0003971, Montana”, https://aquacensus.com/water-systems/montana/big-valley-water-inc-mt0003971 (data as of October 1, 2026).