Public water system · MI0040046
ActiveGuernsey Lake Mobile Home Community
At a glance
Guernsey Lake Mobile Home Community (PWSID MI0040046) is an active community water system in Barry County, Montana. It reports serving 100 people through 40 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, none is health-based, and the most recent began in November 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
100
Service connections
40
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Guernsey Lake Mobile Home Community compare with other water systems in Barry County?
By EPA's size categories, Guernsey Lake Mobile Home Community is a very small system (500 people or fewer). Barry County has 1 active public water system, and Guernsey Lake Mobile Home Community is the largest of them by population served. Its population served is roughly in line with the county average of 100 people per system, and accounts for 100% of the 100 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 Guernsey Lake Mobile Home Community 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 Guernsey Lake Mobile Home Community?
EPA lists Guernsey Lake Mobile Home Community as privately owned. The MI state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 1 of the 1 active systems in Barry County (100%) are also privately owned.
Does Guernsey Lake Mobile Home Community have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in November 2025. The violations listed here began between January 2022 and November 2025. By type: 8 monitoring and reporting, 2 public notice, recordkeeping or other, 1 monitoring and 1 reporting. The contaminant or rule involved most often is Revised Total Coliform Rule (2 of them). EPA lists 11 as resolved and 1 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2025-11-14 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Unaddressed |
| 2025-09-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-11-11 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2024-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | p-Dichlorobenzenecode 2969 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | o-Dichlorobenzenecode 2968 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | cis-1,2-Dichloroethylenecode 2380 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloroethanecode 2980 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | trans-1,2-Dichloroethylenecode 2979 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,1-Trichloroethanecode 2981 | No | Resolved |
| 2022-01-01 | 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.
Guernsey Lake Mobile Home Community: frequently asked questions
Who runs Guernsey Lake Mobile Home Community?
Guernsey Lake Mobile Home Community (PWSID MI0040046) is a community water system privately owned. It is regulated by the MI state drinking water program.
How many people does Guernsey Lake Mobile Home Community serve?
Guernsey Lake Mobile Home Community reports serving 100 people through 40 service connections in Barry County, Montana.
Where does Guernsey Lake Mobile Home Community 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 Guernsey Lake Mobile Home Community 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 November 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 Guernsey Lake Mobile Home Community'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 November 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the MI state drinking water program.
Where can I find Guernsey Lake Mobile Home Community's water quality report?
As a community water system, Guernsey Lake Mobile Home Community 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.
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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, “Guernsey Lake Mobile Home Community, PWSID MI0040046, Montana”, https://aquacensus.com/water-systems/montana/guernsey-lake-mobile-home-community-mi0040046 (data as of October 1, 2026).