Public water system · MN1820009
ActiveLake Elmo
At a glance
Lake Elmo (PWSID MN1820009) is an active community water system in Washington County, Minnesota. It reports serving 10,978 people through 3,540 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
10,978
Service connections
3,540
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Lake Elmo compare with other water systems in Washington County?
By EPA's size categories, Lake Elmo is a large system (10,001 to 100,000 people). Washington County has 192 active public water systems. Its population served is about 8 times the county average of 1,376 people per system, and accounts for 4.2% of the 264,205 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 Lake Elmo is about 64% above 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 Lake Elmo?
EPA lists Lake Elmo 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. 40 of the 192 active systems in Washington County (21%) are also owned by a local government.
Does Lake Elmo have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2024. The violations listed here began between October 2024 and October 2024. By type: 12 monitoring and reporting. The contaminants or rules involved are Alachlor (Lasso), Heptachlor, Methoxychlor and Benzo(a)pyrene. EPA lists 12 as archived. 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 |
|---|---|---|---|---|
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Alachlor (Lasso)code 2051 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Heptachlorcode 2065 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Methoxychlorcode 2015 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Benzo(a)pyrenecode 2306 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) phthalatecode 2039 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Lindane (gamma-BHC)code 2010 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Atrazinecode 2050 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Endrincode 2005 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) adipatecode 2035 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Simazinecode 2037 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Hexachlorocyclopentadienecode 2042 | No | Archived |
| 2024-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlordanecode 2959 | No | Archived |
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.
Lake Elmo: frequently asked questions
Who runs Lake Elmo?
Lake Elmo (PWSID MN1820009) is a community water system owned by a local government. It is regulated by the MN state drinking water program.
How many people does Lake Elmo serve?
Lake Elmo reports serving 10,978 people through 3,540 service connections in Washington County, Minnesota.
Where does Lake Elmo 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 Lake Elmo 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 October 2024. 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 Lake Elmo'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 October 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the MN state drinking water program.
Where can I find Lake Elmo's water quality report?
As a community water system, Lake Elmo 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 Washington County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Woodbury | Washington | 82,643 | Community | Groundwater |
| Cottage Grove | Washington | 42,760 | Community | Groundwater |
| Oakdale | Washington | 30,144 | Community | Groundwater |
| Stillwater | Washington | 19,462 | Community | Groundwater |
| Hugo | Washington | 12,047 | Community | Groundwater |
| Forest Lake | Washington | 11,800 | 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, “Lake Elmo, PWSID MN1820009, Minnesota”, https://aquacensus.com/water-systems/minnesota/lake-elmo-mn1820009 (data as of October 1, 2026).