Public water system · WI1570664
ActiveLake Delton Waterworks
At a glance
Lake Delton Waterworks (PWSID WI1570664) is an active community water system in Sauk County, Wisconsin. It reports serving 2,914 people through 1,079 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 4 violations for this system; none is health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
2,914
Service connections
1,079
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Lake Delton Waterworks compare with other water systems in Sauk County?
By EPA's size categories, Lake Delton Waterworks is a small system (501 to 3,300 people). Sauk County has 199 active public water systems, and Lake Delton Waterworks is the 6th-largest of them by population served. Its population served is about 8.5 times the county average of 342 people per system, and accounts for 4.3% of the 68,062 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 Lake Delton Waterworks is about 57% 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 Lake Delton Waterworks?
EPA lists Lake Delton 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. 28 of the 199 active systems in Sauk County (14%) are also owned by a local government.
Does Lake Delton Waterworks have drinking water violations?
EPA's records list 4 violations for this system; none is health-based, and the most recent began in July 2025. The violations listed here began between July 2002 and July 2025. By type: 3 public notice, recordkeeping or other and 1 monitoring and reporting. The contaminant or rule involved most often is Consumer Confidence Rule (3 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 |
|---|---|---|---|---|
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2003-09-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2002-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | 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.
Lake Delton Waterworks: frequently asked questions
Who runs Lake Delton Waterworks?
Lake Delton Waterworks (PWSID WI1570664) is a community water system owned by a local government. It is regulated by the WI state drinking water program.
How many people does Lake Delton Waterworks serve?
Lake Delton Waterworks reports serving 2,914 people through 1,079 service connections in Sauk County, Wisconsin.
Where does Lake Delton 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 Lake Delton Waterworks have any drinking water violations?
EPA's records list 4 violations for this system; none is health-based, and the most recent began in July 2025. 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 Lake Delton 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 4 violations for this system; none is health-based, and the most recent began in July 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the WI state drinking water program.
Where can I find Lake Delton Waterworks' water quality report?
As a community water system, Lake Delton 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 Sauk County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Baraboo Waterworks | Sauk | 12,703 | Community | Groundwater |
| Reedsburg Waterworks | Sauk | 9,984 | Community | Groundwater |
| Ho Chunk Casino | Sauk | 5,486 | Non-transient non-community | Groundwater |
| Prairie Du Sac Waterworks | Sauk | 4,006 | Community | Groundwater |
| Sauk City Waterworks | Sauk | 3,518 | Community | Groundwater |
| Spring Green Waterworks | Sauk | 1,626 | 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, “Lake Delton Waterworks, PWSID WI1570664, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/lake-delton-waterworks-wi1570664 (data as of October 1, 2026).