Public water system · MN1170003
ActiveMountain Lake
At a glance
Mountain Lake (PWSID MN1170003) is an active community water system in Cottonwood County, Minnesota. It reports serving 2,018 people through 827 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 2 violations for this system; none is health-based, and the most recent began in October 2020.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
2,018
Service connections
827
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Mountain Lake compare with other water systems in Cottonwood County?
By EPA's size categories, Mountain Lake is a small system (501 to 3,300 people). Cottonwood County has 11 active public water systems, and Mountain Lake is the 3rd-largest of them by population served. Its population served is about 57% above the county average of 1,288 people per system, and accounts for 14% of the 14,164 people reported by systems filed under the county. Across Minnesota, the 6,465 active systems average 820 people each. Nationally, the average active community water system reports serving 6,703 people, so Mountain Lake 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. Minnesota has 987 active community water systems, 15% of the state's 6,465 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 6,261 Minnesota systems (97%) list groundwater as their primary source.
Who owns and regulates Mountain Lake?
EPA lists Mountain Lake as owned by a local government. The MN state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 8 of the 11 active systems in Cottonwood County (73%) are also owned by a local government.
Does Mountain Lake have drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in October 2020. The violations listed here began between December 1991 and October 2020. By type: 2 monitoring and reporting. The contaminants or rules involved are Lead and Copper Rule and Total coliform bacteria (TCR). EPA lists 1 as resolved and 1 as archived. 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. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2020-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1991-12-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Archived |
All 2 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.
Mountain Lake: frequently asked questions
Who runs Mountain Lake?
Mountain Lake (PWSID MN1170003) is a community water system owned by a local government. It is regulated by the MN state drinking water program.
How many people does Mountain Lake serve?
Mountain Lake reports serving 2,018 people through 827 service connections in Cottonwood County, Minnesota.
Where does Mountain Lake 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 Mountain Lake have any drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in October 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 Mountain Lake'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. EPA's records list 2 violations for this system; none is health-based, and the most recent began in October 2020. For current results, consult the system's annual water quality report, EPA ECHO, or the MN state drinking water program.
Where can I find Mountain Lake's water quality report?
As a community water system, Mountain Lake 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 Cottonwood County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Red Rock Rural Water System | Cottonwood | 5,840 | Community | Groundwater |
| Windom | Cottonwood | 4,646 | Community | Groundwater |
| Westbrook | Cottonwood | 785 | Community | Groundwater |
| Jeffers | Cottonwood | 369 | Community | Purchased groundwater |
| Storden | Cottonwood | 215 | Community | Purchased groundwater |
| Bingham Lake | Cottonwood | 128 | Community | Purchased 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, “Mountain Lake, PWSID MN1170003, Minnesota”, https://aquacensus.com/water-systems/minnesota/mountain-lake-mn1170003 (data as of October 1, 2026).