Public water system · WI4390281
ActiveMontello Waterworks
At a glance
Montello Waterworks (PWSID WI4390281) is an active community water system in Marquette County, Wisconsin. It reports serving 1,329 people through 492 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, 5 are health-based, and the most recent began in October 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,329
Service connections
492
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Montello Waterworks compare with other water systems in Marquette County?
By EPA's size categories, Montello Waterworks is a small system (501 to 3,300 people). Marquette County has 157 active public water systems, and Montello Waterworks is the 3rd-largest of them by population served. Its population served is about 11 times the county average of 118 people per system, and accounts for 7.2% of the 18,458 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 Montello 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 Montello Waterworks?
EPA lists Montello 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. 13 of the 157 active systems in Marquette County (8.3%) are also owned by a local government.
Does Montello Waterworks have drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in October 2025. The violations listed here began between October 1993 and October 2025. By type: 3 public notice, recordkeeping or other, 3 required treatment not met, 3 monitoring and reporting, 2 contaminant level above the legal limit and 1 reporting. The contaminant or rule involved most often is Lead and Copper Rule Revisions (2 of them). EPA lists 9 as resolved and 3 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 |
|---|---|---|---|---|
| 2025-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Unaddressed |
| 2025-04-29 | Required treatment not metFailure To Address Deficiency · code 45 | Groundwater Rulecode 0700 | Yes | Resolved |
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Resolved |
| 2024-10-17 | ReportingLSL Reporting · code 4G | Lead and Copper Rule Revisionscode 5200 | No | Resolved |
| 2024-10-17 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Unaddressed |
| 2024-10-17 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Unaddressed |
| 2014-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2014-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2009-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1996-07-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1994-07-01 | Required treatment not metOCCT/SOWT Study/Recommendation · code 57 | Lead and Copper Rulecode 5000 | Yes | Resolved |
| 1993-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | 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.
Montello Waterworks: frequently asked questions
Who runs Montello Waterworks?
Montello Waterworks (PWSID WI4390281) is a community water system owned by a local government. It is regulated by the WI state drinking water program.
How many people does Montello Waterworks serve?
Montello Waterworks reports serving 1,329 people through 492 service connections in Marquette County, Wisconsin.
Where does Montello 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 Montello Waterworks have any drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in October 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 Montello 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, 5 are health-based, and the most recent began in October 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 Montello Waterworks' water quality report?
As a community water system, Montello 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 Marquette County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Wi Dot Rest Area 81 Southbound | Marquette | 1,400 | Transient non-community | Groundwater |
| Wi Dot Rest Area 82 Northbound | Marquette | 1,350 | Transient non-community | Groundwater |
| Mcdonalds Westfield | Marquette | 1,040 | Non-transient non-community | Groundwater |
| Kwik Trip #1722 | Marquette | 999 | Transient non-community | Groundwater |
| Brakebush Bros Inc. | Marquette | 898 | Non-transient non-community | Groundwater |
| Burger King Westfield | Marquette | 535 | Non-transient non-community | Groundwater |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Montello Waterworks, PWSID WI4390281, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/montello-waterworks-wi4390281 (data as of October 1, 2026).