Public water system · MT0003261
ActiveGrinell Estates Hoa
At a glance
Grinell Estates Hoa (PWSID MT0003261) is an active community water system in Missoula County, Montana. It reports serving 48 people through 20 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, 4 are health-based, and the most recent began in July 2011.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
48
Service connections
20
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Grinell Estates Hoa compare with other water systems in Missoula County?
By EPA's size categories, Grinell Estates Hoa is a very small system (500 people or fewer). Missoula County has 244 active public water systems. Its population served is well below the county average of 576 people per system, and accounts for less than 0.1% of the 140,505 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 Grinell Estates Hoa 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 Grinell Estates Hoa?
EPA lists Grinell Estates Hoa 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. 201 of the 244 active systems in Missoula County (82%) are also privately owned.
Does Grinell Estates Hoa have drinking water violations?
Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in July 2011. The violations listed here began between January 1996 and July 2011. By type: 6 monitoring and reporting, 4 contaminant level above the legal limit and 2 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2011-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2008-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2007-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2006-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2005-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2005-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2004-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2004-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2002-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1997-01-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1996-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 1996-01-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | 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.
Grinell Estates Hoa: frequently asked questions
Who runs Grinell Estates Hoa?
Grinell Estates Hoa (PWSID MT0003261) is a community water system privately owned. It is regulated by the MT state drinking water program.
How many people does Grinell Estates Hoa serve?
Grinell Estates Hoa reports serving 48 people through 20 service connections in Missoula County, Montana.
Where does Grinell Estates Hoa 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 Grinell Estates Hoa have any drinking water violations?
Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in July 2011. 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 Grinell Estates Hoa'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, 4 are health-based, and the most recent began in July 2011. For current results, consult the system's annual water quality report, EPA ECHO, or the MT state drinking water program.
Where can I find Grinell Estates Hoa's water quality report?
As a community water system, Grinell Estates Hoa 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 Missoula County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Missoula Water | Missoula | 68,200 | Community | Groundwater |
| University of Montana | Missoula | 15,000 | Non-transient non-community | Purchased groundwater |
| Lolo Water and Sewer Dist | Missoula | 3,315 | Community | Groundwater |
| Town Pump Bonner 1 | Missoula | 2,460 | Non-transient non-community | Groundwater |
| Clearwater Junction Rest Area | Missoula | 2,002 | Transient non-community | Groundwater |
| Seeley Lake Water District | Missoula | 1,575 | Community | 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, “Grinell Estates Hoa, PWSID MT0003261, Montana”, https://aquacensus.com/water-systems/montana/grinell-estates-hoa-mt0003261 (data as of October 1, 2026).