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Public water system · WI6560087

Active

Hudson Waterworks

At a glance

Hudson Waterworks (PWSID WI6560087) is an active community water system in St. Croix County, Wisconsin. It reports serving 18,558 people through 15,121 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 8 violations for this system; 2 are health-based, and the most recent began in October 2024.

Dataset updated . Source: EPA SDWIS/ECHO public records.

Population served

18,558

Service connections

15,121

Primary source

GW

Groundwater

System type

CWS

Community water system

System record

PWSIDWI6560087
System typeCommunity water system
Activity statusActive
Population served18,558
Service connections15,121
Primary water sourceGroundwater
Owner typeLocal government
Primacy agencyWI state drinking water program
City servedHudson
StateWisconsin
ZIP—
CountySt. Croix County

How does Hudson Waterworks compare with other water systems in St. Croix County?

By EPA's size categories, Hudson Waterworks is a large system (10,001 to 100,000 people). St. Croix County has 165 active public water systems, and Hudson Waterworks is the largest of them by population served. Its population served is about 53 times the county average of 349 people per system, and accounts for 32% of the 57,590 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 Hudson Waterworks is about 177% above 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 Hudson Waterworks?

EPA lists Hudson 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. 21 of the 165 active systems in St. Croix County (13%) are also owned by a local government.

Does Hudson Waterworks have drinking water violations?

EPA's records list 8 violations for this system; 2 are health-based, and the most recent began in October 2024. The violations listed here began between October 2008 and October 2024. By type: 4 monitoring and reporting, 2 public notice, recordkeeping or other and 2 required treatment not met. The contaminant or rule involved most often is Groundwater Rule (2 of them). EPA lists 7 as resolved and 1 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.

BeganViolationContaminant or ruleHealth-basedStatus
2024-10-17Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75Public Noticecode 7500NoUnaddressed
2024-10-17Required treatment not metLSL Inventory · code 2ELead and Copper Rule Revisionscode 5200YesResolved
2024-01-01Monitoring and reportingLead Consumer Notice · code 66Lead and Copper Rulecode 5000NoResolved
2015-10-29Public notice, recordkeeping or otherNotification, State · code 05Groundwater Rulecode 0700NoResolved
2015-08-02Required treatment not metFailure To Address Deficiency · code 45Groundwater Rulecode 0700YesResolved
2010-01-02Monitoring and reportingFailure Submit IDSE/Subpart V Plan Rpt · code 35Stage 2 Disinfectants and Disinfection Byproducts Rulecode 0600NoResolved
2008-10-01Monitoring and reportingMonitoring, Routine (IDSE) · code 30Total trihalomethanes (TTHM)code 2950NoResolved
2008-10-01Monitoring and reportingMonitoring, Routine (IDSE) · code 30Haloacetic acids (HAA5)code 2456NoResolved

All 8 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.

Hudson Waterworks: frequently asked questions

Who runs Hudson Waterworks?

Hudson Waterworks (PWSID WI6560087) is a community water system owned by a local government. It is regulated by the WI state drinking water program.

How many people does Hudson Waterworks serve?

Hudson Waterworks reports serving 18,558 people through 15,121 service connections in St. Croix County, Wisconsin.

Where does Hudson 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 Hudson Waterworks have any drinking water violations?

EPA's records list 8 violations for this system; 2 are health-based, and the most recent began in October 2024. 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 Hudson 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 8 violations for this system; 2 are health-based, and the most recent began in October 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the WI state drinking water program.

Where can I find Hudson Waterworks' water quality report?

As a community water system, Hudson 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 St. Croix County

Water systemCountyPopulation servedTypeSource
New Richmond WaterworksSt. Croix10,824CommunityGroundwater
Baldwin WaterworksSt. Croix4,440CommunityGroundwater
Somerset WaterworksSt. Croix3,334CommunityGroundwater
Hammond WaterworksSt. Croix1,884CommunityGroundwater
Roberts WaterworksSt. Croix1,872CommunityGroundwater
Woodville WaterworksSt. Croix1,386CommunityGroundwater

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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, “Hudson Waterworks, PWSID WI6560087, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/hudson-waterworks-wi6560087 (data as of October 1, 2026).