Public water system · WI6620328
ActiveOsseo Waterworks
At a glance
Osseo Waterworks (PWSID WI6620328) is an active community water system in Trempealeau County, Wisconsin. It reports serving 1,701 people through 926 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 5 violations for this system; 1 is health-based, and the most recent began in January 2008.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,701
Service connections
926
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Osseo Waterworks compare with other water systems in Trempealeau County?
By EPA's size categories, Osseo Waterworks is a small system (501 to 3,300 people). Trempealeau County has 77 active public water systems, and Osseo Waterworks is the 4th-largest of them by population served. Its population served is about 6.6 times the county average of 259 people per system, and accounts for 8.5% of the 19,945 people reported by systems filed under the county. Across Wisconsin, the 11,056 active systems average 469 people each. Nationally, the average active community water system reports serving 6,703 people, so Osseo Waterworks 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. Wisconsin has 1,053 active community water systems, 9.5% of the state's 11,056 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 10,978 Wisconsin systems (99%) list groundwater as their primary source.
Who owns and regulates Osseo Waterworks?
EPA lists Osseo Waterworks as owned by a local government. The WI state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 18 of the 77 active systems in Trempealeau County (23%) are also owned by a local government.
Does Osseo Waterworks have drinking water violations?
EPA's records list 5 violations for this system; 1 is health-based, and the most recent began in January 2008. The violations listed here began between February 1991 and January 2008. By type: 4 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 of them). EPA lists 4 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 |
|---|---|---|---|---|
| 2008-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 1998-12-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1996-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1991-02-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Archived |
All 5 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.
Osseo Waterworks: frequently asked questions
Who runs Osseo Waterworks?
Osseo Waterworks (PWSID WI6620328) is a community water system owned by a local government. It is regulated by the WI state drinking water program.
How many people does Osseo Waterworks serve?
Osseo Waterworks reports serving 1,701 people through 926 service connections in Trempealeau County, Wisconsin.
Where does Osseo Waterworks 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 Osseo Waterworks have any drinking water violations?
EPA's records list 5 violations for this system; 1 is health-based, and the most recent began in January 2008. 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 Osseo Waterworks' 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 5 violations for this system; 1 is health-based, and the most recent began in January 2008. For current results, consult the system's annual water quality report, EPA ECHO, or the WI state drinking water program.
Where can I find Osseo Waterworks' water quality report?
As a community water system, Osseo Waterworks 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 Trempealeau County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Arcadia Waterworks | Trempealeau | 3,737 | Community | Groundwater |
| Trempealeau Waterworks | Trempealeau | 1,888 | Community | Groundwater |
| Whitehall Waterworks | Trempealeau | 1,820 | Community | Groundwater |
| Galesville Waterworks | Trempealeau | 1,679 | Community | Groundwater |
| Independence Waterworks | Trempealeau | 1,500 | Community | Groundwater |
| Blair Waterworks | Trempealeau | 1,280 | 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, “Osseo Waterworks, PWSID WI6620328, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/osseo-waterworks-wi6620328 (data as of October 1, 2026).