Public water system · WI4050351
ActiveDenmark Waterworks
At a glance
Denmark Waterworks (PWSID WI4050351) is an active community water system in Brown County, Wisconsin. It reports serving 2,684 people through 976 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in March 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
2,684
Service connections
976
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Denmark Waterworks compare with other water systems in Brown County?
By EPA's size categories, Denmark Waterworks is a small system (501 to 3,300 people). Brown County has 148 active public water systems. Its population served is about 61% above the county average of 1,666 people per system, and accounts for 1.1% of the 246,537 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 Denmark Waterworks is about 60% 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 43 Wisconsin systems (0.4%) list purchased surface water as their primary source.
Who owns and regulates Denmark Waterworks?
EPA lists Denmark 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. 41 of the 148 active systems in Brown County (28%) are also owned by a local government.
Does Denmark Waterworks have drinking water violations?
Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in March 2026. The violations listed here began between January 2005 and March 2026. By type: 5 public notice, recordkeeping or other, 3 required treatment not met, 2 monitoring and 2 monitoring and reporting. The contaminant or rule involved most often is Public Notice (4 of them). EPA lists 10 as resolved and 2 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 |
|---|---|---|---|---|
| 2026-03-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Archived |
| 2024-10-17 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Resolved |
| 2024-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2011-10-01 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2009-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2006-01-01 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2006-01-01 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2006-01-01 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2005-07-01 | Required treatment not metOCCT/SOWT Study/Recommendation · code 57 | Lead and Copper Rulecode 5000 | Yes | Resolved |
| 2005-07-01 | Required treatment not metPublic Education · code 65 | Lead and Copper Rulecode 5000 | Yes | Resolved |
| 2005-01-01 | Monitoring and reportingWater Quality Parameter M/R · code 53 | Lead and Copper Rulecode 5000 | No | Archived |
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.
Denmark Waterworks: frequently asked questions
Who runs Denmark Waterworks?
Denmark Waterworks (PWSID WI4050351) is a community water system owned by a local government. It is regulated by the WI state drinking water program.
How many people does Denmark Waterworks serve?
Denmark Waterworks reports serving 2,684 people through 976 service connections in Brown County, Wisconsin.
Where does Denmark Waterworks get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Denmark Waterworks have any drinking water violations?
Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in March 2026. 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 Denmark 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. Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in March 2026. For current results, consult the system's annual water quality report, EPA ECHO, or the WI state drinking water program.
Where can I find Denmark Waterworks' water quality report?
As a community water system, Denmark 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 Brown County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Green Bay Waterworks | Brown | 107,369 | Community | Surface water |
| De Pere Waterworks Sa 1 | Brown | 25,660 | Community | Purchased surface water |
| Howard Waterworks | Brown | 21,133 | Community | Purchased surface water |
| Ashwaubenon Waterworks | Brown | 17,730 | Community | Purchased surface water |
| Bellevue Waterworks | Brown | 16,715 | Community | Purchased surface water |
| Allouez Waterworks | Brown | 13,923 | Community | Purchased surface water |
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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, “Denmark Waterworks, PWSID WI4050351, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/denmark-waterworks-wi4050351 (data as of October 1, 2026).