Public water system · WI6420296
ActiveNorwalk Waterworks
At a glance
Norwalk Waterworks (PWSID WI6420296) is an active community water system in Monroe County, Wisconsin. It reports serving 653 people through 230 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 7 violations for this system; 1 is health-based, and the most recent began in March 2010.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
653
Service connections
230
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Norwalk Waterworks compare with other water systems in Monroe County?
By EPA's size categories, Norwalk Waterworks is a small system (501 to 3,300 people). Monroe County has 102 active public water systems, and Norwalk Waterworks is the 6th-largest of them by population served. Its population served is about 70% above the county average of 385 people per system, and accounts for 1.7% of the 39,274 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 Norwalk Waterworks 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 Norwalk Waterworks?
EPA lists Norwalk 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. 14 of the 102 active systems in Monroe County (14%) are also owned by a local government.
Does Norwalk Waterworks have drinking water violations?
EPA's records list 7 violations for this system; 1 is health-based, and the most recent began in March 2010. The violations listed here began between April 1995 and March 2010. By type: 6 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (5 of them). EPA lists 7 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 |
|---|---|---|---|---|
| 2010-03-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2008-05-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 1995-10-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | 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 |
| 1995-04-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 7 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.
Norwalk Waterworks: frequently asked questions
Who runs Norwalk Waterworks?
Norwalk Waterworks (PWSID WI6420296) is a community water system owned by a local government. It is regulated by the WI state drinking water program.
How many people does Norwalk Waterworks serve?
Norwalk Waterworks reports serving 653 people through 230 service connections in Monroe County, Wisconsin.
Where does Norwalk 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 Norwalk Waterworks have any drinking water violations?
EPA's records list 7 violations for this system; 1 is health-based, and the most recent began in March 2010. 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 Norwalk 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 7 violations for this system; 1 is health-based, and the most recent began in March 2010. For current results, consult the system's annual water quality report, EPA ECHO, or the WI state drinking water program.
Where can I find Norwalk Waterworks' water quality report?
As a community water system, Norwalk 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 Monroe County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Sparta Waterworks | Monroe | 10,025 | Community | Groundwater |
| Fort Mccoy North Post | Monroe | 10,000 | Community | Groundwater |
| Tomah Waterworks | Monroe | 9,192 | Community | Groundwater |
| Cashton Waterworks | Monroe | 1,120 | Community | Groundwater |
| Brookwood High School | Monroe | 700 | Non-transient non-community | Groundwater |
| Warrens Waterworks | Monroe | 540 | 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, “Norwalk Waterworks, PWSID WI6420296, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/norwalk-waterworks-wi6420296 (data as of October 1, 2026).