Public water system · WI7371256
ActiveHatley Waterworks
At a glance
Hatley Waterworks (PWSID WI7371256) is an active community water system in Marathon County, Wisconsin. It reports serving 550 people through 191 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2022.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
550
Service connections
191
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Hatley Waterworks compare with other water systems in Marathon County?
By EPA's size categories, Hatley Waterworks is a small system (501 to 3,300 people). Marathon County has 196 active public water systems. Its population served is roughly in line with the county average of 528 people per system, and accounts for 0.5% of the 103,490 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 Hatley 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 Hatley Waterworks?
EPA lists Hatley 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. 43 of the 196 active systems in Marathon County (22%) are also owned by a local government.
Does Hatley Waterworks have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2022. The violations listed here began between April 1995 and October 2022. By type: 10 monitoring and reporting and 2 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (4 of them). EPA lists 11 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2022-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2022-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2012-01-01 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Unaddressed |
| 2002-12-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2000-01-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1996-08-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1995-10-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1995-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Carbon tetrachloridecode 2982 | No | Resolved |
| 1995-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1-Dichloroethylenecode 2977 | No | Resolved |
| 1995-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloroethanecode 2980 | No | Resolved |
| 1995-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dichloromethanecode 2964 | No | Resolved |
| 1995-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,1-Trichloroethanecode 2981 | 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.
Hatley Waterworks: frequently asked questions
Who runs Hatley Waterworks?
Hatley Waterworks (PWSID WI7371256) is a community water system owned by a local government. It is regulated by the WI state drinking water program.
How many people does Hatley Waterworks serve?
Hatley Waterworks reports serving 550 people through 191 service connections in Marathon County, Wisconsin.
Where does Hatley 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 Hatley Waterworks 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 October 2022. 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 Hatley 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, none is health-based, and the most recent began in October 2022. For current results, consult the system's annual water quality report, EPA ECHO, or the WI state drinking water program.
Where can I find Hatley Waterworks' water quality report?
As a community water system, Hatley 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 Marathon County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Wausau Waterworks | Marathon | 39,994 | Community | Groundwater |
| Weston Municipal Utilities | Marathon | 16,000 | Community | Groundwater |
| Kronenwetter Water & Sewer Utility | Marathon | 6,931 | Community | Groundwater |
| Rib Mountain Water Utility | Marathon | 6,398 | Community | Groundwater |
| Mosinee Waterworks | Marathon | 3,406 | Community | Groundwater |
| Rothschild Waterworks | Marathon | 3,190 | 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, “Hatley Waterworks, PWSID WI7371256, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/hatley-waterworks-wi7371256 (data as of October 1, 2026).