Lake Mills Waterworks

PWSID: WI1280108

6 active violations (non-health-based)
This system has unresolved violations related to monitoring, reporting, or procedural requirements, but none involve contaminant levels exceeding EPA health limits.

This system has more violations on record than 98% of water systems in Wisconsin.

Violation trend: 0.4 per year over the last 5 years, down from 3.6 per year in the previous 5.

System Details

Population Served6,211
Service Connections2,607
Water SourceGroundwater
System TypeCommunity Water System
OwnerLocal Government
StatusActive
CityLake Mills
EPA ZIP on File53551-1632

Areas Served

  • Lake Mills, Jefferson County

Lead & Copper Testing

ContaminantLevelEPA Action LevelStatus
Lead (90th percentile)0.0180 mg/L0.015 mg/LExceeds Action Level
Lead (90th percentile)0.0110 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0073 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0071 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0065 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0059 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0057 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0046 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0039 mg/L0.015 mg/LBelow Action Level

6 Active Violations

ContaminantViolationDateHealth-BasedStatus
5000MR2016-10-01Open
5000MR2014-01-01Open
7500Other2012-01-01Open
7500Other2012-01-01Open
7500Other2011-01-01Open
7500Other2009-05-01Open

Violation History (39 total)

ContaminantViolationDateHealth-BasedStatus
5000TT2022-09-17YesReturned to Compliance
5000TT2022-09-17YesReturned to Compliance
7000Other2020-07-01Returned to Compliance
7000Other2020-07-01Returned to Compliance
7500Other2018-01-01Returned to Compliance
5000TT2017-10-01YesReturned to Compliance
4010MCL
Measured: 5.50 PCI/L (limit: 5.50 PCI/L)
2017-07-01YesReturned to Compliance
5000MR2017-07-01Returned to Compliance
7500Other2017-06-23Returned to Compliance
5000MR2017-04-01Returned to Compliance
7500Other2017-01-01Returned to Compliance
5000MR2017-01-01Returned to Compliance
5000MR2017-01-01Returned to Compliance
5000MR2017-01-01Returned to Compliance
5000MR2017-01-01Returned to Compliance
5000MR2017-01-01Returned to Compliance
5000MR2017-01-01Returned to Compliance
5000MR2017-01-01Returned to Compliance
5000MR2016-07-01Returned to Compliance
5000TT2016-04-01YesReturned to Compliance
5000TT2016-01-01YesReturned to Compliance
5000TT2016-01-01YesReturned to Compliance
7500Other2016-01-01Returned to Compliance
7500Other2016-01-01Returned to Compliance
5000MR2016-01-01Returned to Compliance
5000MR2013-06-01Returned to Compliance
5000MR2013-04-01Returned to Compliance
5000MR2012-10-01Returned to Compliance
5000MR2012-04-01Returned to Compliance
5000TT2012-01-01YesReturned to Compliance
5000MR2011-10-01Returned to Compliance
7000Other2010-07-01Returned to Compliance
7000Other2009-07-01Returned to Compliance

Understanding This Water System's Record

Lake Mills Waterworks is a community water system water system that draws from groundwater sources and serves a population of 6,211 in Lake Mills, Wisconsin. This page shows its complete compliance history as reported to the EPA's Safe Drinking Water Information System (SDWIS), the federal database that tracks every public water system in the United States.

What Do These Violations Mean?

Health-based violations mean the system exceeded an EPA maximum contaminant level (MCL) or failed to provide required treatment. These indicate potential health risks from contaminants like lead, arsenic, bacteria, nitrates, or disinfection byproducts. Non-health-based violations involve monitoring, reporting, or procedural requirements — the system missed a testing deadline or failed to notify customers, but contaminant levels were not necessarily unsafe.

What Should You Do?

Your water utility is required to publish an annual Consumer Confidence Report (CCR) that details test results and any violations. If your system has active health-based violations, consider a certified water filter rated for the specific contaminants involved. The contaminant guides on this site explain health risks and filter options for common pollutants. For the most current results, contact your water utility directly — EPA data can lag weeks or months behind real-time testing.