Public water system · WI1280367
ActiveRock Lake Co Park - Upper
At a glance
Rock Lake Co Park - Upper (PWSID WI1280367) is an active transient non-community water system in Jefferson County, Wisconsin. It reports serving 25 people through 1 service connection. 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; all are health-based, and the most recent began in October 1995.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
25
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Rock Lake Co Park - Upper compare with other water systems in Jefferson County?
By EPA's size categories, Rock Lake Co Park - Upper is a very small system (500 people or fewer). Jefferson County has 195 active public water systems. Its population served is well below the county average of 453 people per system, and accounts for less than 0.1% of the 88,343 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 Rock Lake Co Park - Upper is well below 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 Rock Lake Co Park - Upper?
EPA lists Rock Lake Co Park - Upper 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. 34 of the 195 active systems in Jefferson County (17%) are also owned by a local government.
Does Rock Lake Co Park - Upper have drinking water violations?
EPA's records list 2 violations for this system; all are health-based, and the most recent began in October 1995. The violations listed here began between August 1995 and October 1995. By type: 2 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (2 of them). EPA lists 2 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 |
|---|---|---|---|---|
| 1995-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1995-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
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.
Rock Lake Co Park - Upper: frequently asked questions
Who runs Rock Lake Co Park - Upper?
Rock Lake Co Park - Upper (PWSID WI1280367) is a transient non-community water system owned by a local government. It is regulated by the WI state drinking water program.
How many people does Rock Lake Co Park - Upper serve?
Rock Lake Co Park - Upper reports serving 25 people through 1 service connection in Jefferson County, Wisconsin.
Where does Rock Lake Co Park - Upper 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 Rock Lake Co Park - Upper have any drinking water violations?
EPA's records list 2 violations for this system; all are health-based, and the most recent began in October 1995. 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 Rock Lake Co Park - Upper'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; all are health-based, and the most recent began in October 1995. For current results, consult EPA ECHO, or the WI state drinking water program.
Where can I find Rock Lake Co Park - Upper's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Rock Lake Co Park - Upper 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 Jefferson County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Watertown Waterworks | Jefferson | 23,945 | Community | Groundwater |
| Fort Atkinson Waterworks | Jefferson | 12,390 | Community | Groundwater |
| Jefferson Waterworks | Jefferson | 7,926 | Community | Groundwater |
| Lake Mills Waterworks | Jefferson | 6,211 | Community | Groundwater |
| Waterloo Waterworks | Jefferson | 3,520 | Community | Groundwater |
| Johnson Creek Waterworks | Jefferson | 3,318 | 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, “Rock Lake Co Park - Upper, PWSID WI1280367, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/rock-lake-co-park-upper-wi1280367 (data as of October 1, 2026).