Public water system · MT0004006
ActiveCottonwood Estates
At a glance
Cottonwood Estates (PWSID MT0004006) is an active community water system in Sweet Grass County, Montana. It reports serving 50 people through 17 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, one is health-based, and the most recent began in February 2020.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
50
Service connections
17
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Cottonwood Estates compare with other water systems in Sweet Grass County?
By EPA's size categories, Cottonwood Estates is a very small system (500 people or fewer). Sweet Grass County has 16 active public water systems. Its population served is well below the county average of 457 people per system, and accounts for 0.7% of the 7,304 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 Cottonwood Estates 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 Cottonwood Estates?
EPA lists Cottonwood Estates 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. 13 of the 16 active systems in Sweet Grass County (81%) are also privately owned.
Does Cottonwood Estates have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in February 2020. The violations listed here began between July 2009 and February 2020. By type: 6 public notice, recordkeeping or other, 5 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Consumer Confidence Rule (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 |
|---|---|---|---|---|
| 2020-02-18 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2014-12-30 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2014-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2014-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2013-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2012-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2011-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2011-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2011-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Asbestoscode 1094 | No | Resolved |
| 2010-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2009-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2009-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | 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.
Cottonwood Estates: frequently asked questions
Who runs Cottonwood Estates?
Cottonwood Estates (PWSID MT0004006) is a community water system privately owned. It is regulated by the MT state drinking water program.
How many people does Cottonwood Estates serve?
Cottonwood Estates reports serving 50 people through 17 service connections in Sweet Grass County, Montana.
Where does Cottonwood Estates 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 Cottonwood Estates have any drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in February 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 Cottonwood Estates' 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, one is health-based, and the most recent began in February 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 Cottonwood Estates' water quality report?
As a community water system, Cottonwood Estates 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 Sweet Grass County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Greycliff Rest Area Eastbound | Sweet Grass | 2,500 | Transient non-community | Groundwater |
| Big Timber City of | Sweet Grass | 1,650 | Community | Surface water |
| Greycliff Rest Area Westbound | Sweet Grass | 1,000 | Transient non-community | Groundwater |
| Big Timber Koa | Sweet Grass | 600 | Transient non-community | Groundwater |
| Stillwater East Boulder | Sweet Grass | 380 | Non-transient non-community | Groundwater |
| Town Pump 1033 Big Timber # 2 | Sweet Grass | 318 | Transient non-community | Groundwater |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Cottonwood Estates, PWSID MT0004006, Montana”, https://aquacensus.com/water-systems/montana/cottonwood-estates-mt0004006 (data as of October 1, 2026).