Public water system · WI1110104
ActiveOakwood Terrace
At a glance
Oakwood Terrace (PWSID WI1110104) is an active community water system in Columbia County, Wisconsin. It reports serving 100 people through 68 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2007.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
100
Service connections
68
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Oakwood Terrace compare with other water systems in Columbia County?
By EPA's size categories, Oakwood Terrace is a very small system (500 people or fewer). Columbia County has 140 active public water systems. Its population served is well below the county average of 463 people per system, and accounts for 0.2% 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 community water system reports serving 6,703 people, so Oakwood Terrace 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 Oakwood Terrace?
EPA lists Oakwood Terrace 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 Oakwood Terrace have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2007. The violations listed here began between September 1995 and January 2007. By type: 12 monitoring and reporting. The contaminant or rule involved most often is Combined Radium (-226 and -228) (2 of them). EPA lists 12 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 |
|---|---|---|---|---|
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Radium-226code 4020 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Radium-228code 4030 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Radium-228code 4030 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Uraniumcode 4006 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Uraniumcode 4006 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Radium-226code 4020 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
| 1998-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1995-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
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.
Oakwood Terrace: frequently asked questions
Who runs Oakwood Terrace?
Oakwood Terrace (PWSID WI1110104) is a community water system privately owned. It is regulated by the WI state drinking water program.
How many people does Oakwood Terrace serve?
Oakwood Terrace reports serving 100 people through 68 service connections in Columbia County, Wisconsin.
Where does Oakwood Terrace 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 Oakwood Terrace 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 January 2007. 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 Oakwood Terrace'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 January 2007. For current results, consult the system's annual water quality report, EPA ECHO, or the WI state drinking water program.
Where can I find Oakwood Terrace's water quality report?
As a community water system, Oakwood Terrace 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 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, “Oakwood Terrace, PWSID WI1110104, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/oakwood-terrace-wi1110104 (data as of October 1, 2026).