Public water system · MT0004462
ActiveLower Pioneer Mountain Water System
At a glance
Lower Pioneer Mountain Water System (PWSID MT0004462) is an active community water system in Madison County, Montana. It reports serving 350 people through 210 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in September 2020.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
350
Service connections
210
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Lower Pioneer Mountain Water System compare with other water systems in Madison County?
By EPA's size categories, Lower Pioneer Mountain Water System is a very small system (500 people or fewer). Madison County has 45 active public water systems. Its population served is roughly in line with the county average of 320 people per system, and accounts for 2.4% of the 14,392 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 Lower Pioneer Mountain Water System is well below 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. 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 Lower Pioneer Mountain Water System?
EPA lists Lower Pioneer Mountain Water System 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. 26 of the 45 active systems in Madison County (58%) are also privately owned.
Does Lower Pioneer Mountain Water System have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in September 2020. The violations listed here began between April 2008 and September 2020. By type: 9 monitoring and reporting, 2 contaminant level above the legal limit and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 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 |
|---|---|---|---|---|
| 2020-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, E. coli (RTCR) · code 1A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2020-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2015-02-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2010-12-01 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2010-02-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2009-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2009-03-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Resolved |
| 2008-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
| 2008-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloroethanecode 2980 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dichloromethanecode 2964 | 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.
Lower Pioneer Mountain Water System: frequently asked questions
Who runs Lower Pioneer Mountain Water System?
Lower Pioneer Mountain Water System (PWSID MT0004462) is a community water system privately owned. It is regulated by the MT state drinking water program.
How many people does Lower Pioneer Mountain Water System serve?
Lower Pioneer Mountain Water System reports serving 350 people through 210 service connections in Madison County, Montana.
Where does Lower Pioneer Mountain Water System 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 Lower Pioneer Mountain Water System 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 September 2020. 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 Lower Pioneer Mountain Water System'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 September 2020. For current results, consult the system's annual water quality report, EPA ECHO, or the MT state drinking water program.
Where can I find Lower Pioneer Mountain Water System's water quality report?
As a community water system, Lower Pioneer Mountain Water System 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 Madison County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Big Sky County Water and Sewer Dist 363 | Madison | 4,132 | Community | Groundwater |
| Virginia City Water Dept | Madison | 1,500 | Community | Groundwater |
| Ennis Town of | Madison | 1,400 | Community | Groundwater |
| Sheridan Town of | Madison | 632 | Community | Groundwater |
| Nevada City | Madison | 621 | Transient non-community | Groundwater |
| Earthquake Lake Visitor Center | Madison | 503 | 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, “Lower Pioneer Mountain Water System, PWSID MT0004462, Montana”, https://aquacensus.com/water-systems/montana/lower-pioneer-mountain-water-system-mt0004462 (data as of October 1, 2026).