Public water system · WI1110233
ActiveWillow Mill Campground Main Park Side
At a glance
Willow Mill Campground Main Park Side (PWSID WI1110233) is an active transient non-community water system in Columbia County, Wisconsin. It reports serving 200 people through 80 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 4 violations for this system; 2 are health-based, and the most recent began in May 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
200
Service connections
80
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Willow Mill Campground Main Park Side compare with other water systems in Columbia County?
By EPA's size categories, Willow Mill Campground Main Park Side is a very small system (500 people or fewer). Columbia County has 140 active public water systems. Its population served is about 57% below the county average of 463 people per system, and accounts for 0.3% of the 64,780 people reported by systems filed under the county. Across Wisconsin, the 11,056 active systems average 469 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Willow Mill Campground Main Park Side is about 39% above that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. Wisconsin has 9,112 active transient non-community water systems, 82% 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 Willow Mill Campground Main Park Side?
EPA lists Willow Mill Campground Main Park Side as privately owned. 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. 114 of the 140 active systems in Columbia County (81%) are also privately owned.
Does Willow Mill Campground Main Park Side have drinking water violations?
EPA's records list 4 violations for this system; 2 are health-based, and the most recent began in May 2023. The violations listed here began between June 1999 and May 2023. By type: 2 reporting and 2 contaminant level above the legal limit. The contaminant or rule involved most often is Revised Total Coliform Rule (2 of them). EPA lists 4 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 |
|---|---|---|---|---|
| 2023-05-29 | ReportingReport Startup Procedures Cert Form (RTCR) · code 4C | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-05-10 | ReportingReport Startup Procedures Cert Form (RTCR) · code 4C | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 1999-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1999-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
All 4 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.
Willow Mill Campground Main Park Side: frequently asked questions
Who runs Willow Mill Campground Main Park Side?
Willow Mill Campground Main Park Side (PWSID WI1110233) is a transient non-community water system privately owned. It is regulated by the WI state drinking water program.
How many people does Willow Mill Campground Main Park Side serve?
Willow Mill Campground Main Park Side reports serving 200 people through 80 service connections in Columbia County, Wisconsin.
Where does Willow Mill Campground Main Park Side 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 Willow Mill Campground Main Park Side have any drinking water violations?
EPA's records list 4 violations for this system; 2 are health-based, and the most recent began in May 2023. 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 Willow Mill Campground Main Park Side'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 4 violations for this system; 2 are health-based, and the most recent began in May 2023. For current results, consult EPA ECHO, or the WI state drinking water program.
Where can I find Willow Mill Campground Main Park Side's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Willow Mill Campground Main Park Side is a transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Columbia County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Portage Waterworks | Columbia | 10,437 | Community | Groundwater |
| Columbus Utilities | Columbia | 5,173 | Community | Groundwater |
| Wi Dot Rest Area 12 Dekorra West Bound | Columbia | 3,255 | Transient non-community | Groundwater |
| Wisconsin Dells Waterworks | Columbia | 3,232 | Community | Groundwater |
| Lodi Waterworks | Columbia | 3,146 | Community | Groundwater |
| Poynette Waterworks | Columbia | 2,520 | 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, “Willow Mill Campground Main Park Side, PWSID WI1110233, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/willow-mill-campground-main-park-side-wi1110233 (data as of October 1, 2026).