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Public water system · MT0004512

Active

The Dewey Bar

At a glance

The Dewey Bar (PWSID MT0004512) is an active transient non-community water system in Beaverhead County, Montana. It reports serving 28 people through 1 service connection. Its primary water source is groundwater, 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 January 2025.

Dataset updated . Source: EPA SDWIS/ECHO public records.

Population served

28

Service connections

1

Primary source

GW

Groundwater

System type

TNCWS

Transient non-community water system

System record

PWSIDMT0004512
System typeTransient non-community water system
Activity statusActive
Population served28
Service connections1
Primary water sourceGroundwater
Owner typePrivate
Primacy agencyMT state drinking water program
City servedDivide
StateMontana
ZIP—
CountyBeaverhead County

How does The Dewey Bar compare with other water systems in Beaverhead County?

By EPA's size categories, The Dewey Bar is a very small system (500 people or fewer). Beaverhead County has 48 active public water systems. Its population served is well below the county average of 198 people per system, and accounts for 0.3% of the 9,494 people reported by systems filed under the county. Across Montana, the 2,378 active systems average 489 people each. Nationally, the average active transient non-community water system reports serving 144 people, so The Dewey Bar is well below that figure.

What does “transient non-community water system” mean?

A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. Montana has 1,206 active transient non-community water systems, 51% 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 The Dewey Bar?

EPA lists The Dewey Bar 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. 24 of the 48 active systems in Beaverhead County (50%) are also privately owned.

Does The Dewey Bar have drinking water violations?

Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2025. The violations listed here began between May 2008 and January 2025. By type: 10 monitoring and reporting, 1 monitoring and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (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.

BeganViolationContaminant or ruleHealth-basedStatus
2025-01-01Monitoring and reportingMonitoring, Regular · code 03Nitrate-Nitritecode 1038NoResolved
2021-06-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2018-08-16Monitoring and reportingMonitoring, Source Water (GWR) · code 34E. colicode 3014NoResolved
2016-04-02Public notice, recordkeeping or otherSample Siting Plan Errors (RTCR) · code 5ARevised Total Coliform Rulecode 8000NoResolved
2013-07-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2012-07-01Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24Total coliform bacteria (TCR)code 3100NoResolved
2012-06-01Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25Total coliform bacteria (TCR)code 3100NoResolved
2012-06-01Monitoring and reportingMonitoring, Source Water (GWR) · code 34E. colicode 3014NoResolved
2009-07-01Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25Total coliform bacteria (TCR)code 3100NoResolved
2009-01-01Monitoring and reportingMonitoring, Regular · code 03Nitrate-Nitritecode 1038NoResolved
2008-06-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2008-05-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved

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.

The Dewey Bar: frequently asked questions

Who runs The Dewey Bar?

The Dewey Bar (PWSID MT0004512) is a transient non-community water system privately owned. It is regulated by the MT state drinking water program.

How many people does The Dewey Bar serve?

The Dewey Bar reports serving 28 people through 1 service connection in Beaverhead County, Montana.

Where does The Dewey Bar 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 The Dewey Bar 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 January 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 The Dewey Bar'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 January 2025. For current results, consult EPA ECHO, or the MT state drinking water program.

Where can I find The Dewey Bar's water quality report?

The annual Consumer Confidence Report requirement applies to community water systems. The Dewey Bar is a 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 Beaverhead County

Water systemCountyPopulation servedTypeSource
Dillon City ofBeaverhead4,300CommunityGroundwater
Town Pump Dillon 2Beaverhead924Transient non-communityGroundwater
Bannack St Park Visitor CenterBeaverhead410Transient non-communityGroundwater
Maverick Mountain Resort LLCBeaverhead340Transient non-communityGroundwater under influence of surface water
Keller Subdivision No 2 HoaBeaverhead300CommunityGroundwater
Hildreth Subdivision No 2Beaverhead300CommunityGroundwater

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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, “The Dewey Bar, PWSID MT0004512, Montana”, https://aquacensus.com/water-systems/montana/the-dewey-bar-mt0004512 (data as of October 1, 2026).