Public water system · MN1450008
ActiveOslo
At a glance
Oslo (PWSID MN1450008) is an active community water system in Marshall County, Minnesota. It reports serving 242 people through 186 service connections. Its primary water source is purchased groundwater, and EPA lists it as owned by a local government. EPA's records list 3 violations for this system; none is health-based, and the most recent began in October 2017.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
242
Service connections
186
Primary source
GWP
Purchased groundwater
System type
CWS
Community water system
System record
How does Oslo compare with other water systems in Marshall County?
By EPA's size categories, Oslo is a very small system (500 people or fewer). Marshall County has 17 active public water systems. Its population served is about half of the county average of 467 people per system, and accounts for 3% of the 7,939 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 Oslo 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. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own. 89 Minnesota systems (1.4%) list purchased groundwater as their primary source.
Who owns and regulates Oslo?
EPA lists Oslo 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. 12 of the 17 active systems in Marshall County (71%) are also owned by a local government.
Does Oslo have drinking water violations?
EPA's records list 3 violations for this system; none is health-based, and the most recent began in October 2017. The violations listed here began between July 2014 and October 2017. By type: 3 monitoring and reporting. The contaminants or rules involved are Lead and Copper Rule, Chlorine and Total coliform bacteria (TCR). EPA lists 3 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 |
|---|---|---|---|---|
| 2017-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 3 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.
Oslo: frequently asked questions
Who runs Oslo?
Oslo (PWSID MN1450008) is a community water system owned by a local government. It is regulated by the MN state drinking water program.
How many people does Oslo serve?
Oslo reports serving 242 people through 186 service connections in Marshall County, Minnesota.
Where does Oslo get its water?
EPA SDWIS lists this system's primary water source as purchased groundwater. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own.
Does Oslo have any drinking water violations?
EPA's records list 3 violations for this system; none is health-based, and the most recent began in October 2017. 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 Oslo'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 3 violations for this system; none is health-based, and the most recent began in October 2017. For current results, consult the system's annual water quality report, EPA ECHO, or the MN state drinking water program.
Where can I find Oslo's water quality report?
As a community water system, Oslo 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 Marshall County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Marshall-Polk Rural Water System | Marshall | 3,295 | Community | Groundwater |
| Warren | Marshall | 1,551 | Community | Groundwater |
| Stephen | Marshall | 568 | Community | Purchased groundwater |
| Argyle | Marshall | 533 | Community | Groundwater |
| Alvarado | Marshall | 377 | Community | Purchased groundwater |
| Newfolden | Marshall | 338 | 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, “Oslo, PWSID MN1450008, Minnesota”, https://aquacensus.com/water-systems/minnesota/oslo-mn1450008 (data as of October 1, 2026).