Public water system · WI1230083
ActiveMonticello Waterworks
At a glance
Monticello Waterworks (PWSID WI1230083) is an active community water system in Green County, Wisconsin. It reports serving 1,217 people through 450 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,217
Service connections
450
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Monticello Waterworks compare with other water systems in Green County?
By EPA's size categories, Monticello Waterworks is a small system (501 to 3,300 people). Green County has 52 active public water systems, and Monticello Waterworks is the 6th-largest of them by population served. Its population served is about 125% above the county average of 540 people per system, and accounts for 4.3% of the 28,087 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 Monticello 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 Monticello Waterworks?
EPA lists Monticello 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. 11 of the 52 active systems in Green County (21%) are also owned by a local government.
Does Monticello Waterworks have drinking water violations?
EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in October 2024. The violations listed here began between October 2024 and October 2024. By type: 1 public notice, recordkeeping or other and 1 required treatment not met. The contaminants or rules involved are Public Notice and Lead and Copper Rule Revisions. EPA lists 1 as unaddressed and 1 as resolved. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement. 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 |
|---|---|---|---|---|
| 2024-10-17 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Unaddressed |
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Resolved |
All 2 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.
Monticello Waterworks: frequently asked questions
Who runs Monticello Waterworks?
Monticello Waterworks (PWSID WI1230083) is a community water system owned by a local government. It is regulated by the WI state drinking water program.
How many people does Monticello Waterworks serve?
Monticello Waterworks reports serving 1,217 people through 450 service connections in Green County, Wisconsin.
Where does Monticello 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 Monticello Waterworks have any drinking water violations?
EPA's records list 2 violations for this system; 1 is 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 Monticello 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 2 violations for this system; 1 is 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 Monticello Waterworks' water quality report?
As a community water system, Monticello 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 Green County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Monroe Waterworks | Green | 10,780 | Community | Groundwater |
| Brodhead Waterworks | Green | 3,216 | Community | Groundwater |
| Belleville Waterworks | Green | 2,712 | Community | Groundwater |
| New Glarus Waterworks | Green | 2,348 | Community | Groundwater |
| Brooklyn Waterworks | Green | 1,524 | Community | Groundwater |
| Albany Waterworks | Green | 1,018 | 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, “Monticello Waterworks, PWSID WI1230083, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/monticello-waterworks-wi1230083 (data as of October 1, 2026).