F0/100
Lake Mills Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 6,211 residents · Wisconsin
What's In Lake Mills's Tap Water?
32
Contaminants Tested
1
Exceed EPA Limits
1
Above EPA Goals
2 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 1.60 mg/L | 1.30 mg/L | Over Limit |
Lead (90th percentile) | 0.005 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
1
Violation (last 5yr)
0
Unresolved
1
Health-Related
TIER 2Resolved
Consumer confidence report — late or incomplete delivery
When: September 17, 2022 – October 26, 2022Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Water Utility Details
LAKE MILLS WATERWORKS
Population Served
6,211
Water Source
Groundwater
System ID
WI1280108
Frequently Asked Questions About Lake Mills Water
Is Lake Mills tap water safe to drink?
Lake Mills, Wisconsin tap water receives a grade of F (0/100), which is considered failing. 1 contaminant(s) exceed EPA maximum contaminant levels and 55 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Lake Mills's water?
Of the 32 contaminants tested in Lake Mills's water supply, the most notable include Copper (90th percentile), Lead (90th percentile). 1 contaminant(s) exceed EPA legal limits (MCLs). 2 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Lake Mills have any water quality violations?
Yes, Lake Mills has 55 EPA violation(s) on record, with the most recent in 2022. Violation types include TT, Other, MCL. 11 of these are health-based violations, which are the most serious category.
Do I need a water filter in Lake Mills?
Based on EPA data, using a water filter in Lake Mills is recommended. 1 contaminant(s) exceed legal limits. An NSF-certified filter — such as a reverse osmosis or activated carbon system — can effectively reduce many common contaminants. Choose a filter certified to remove the specific contaminants found in your area.
Where does Lake Mills's tap water come from?
Lake Mills's drinking water is sourced from groundwater and supplied by LAKE MILLS WATERWORKS. The system serves approximately 6,211 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Lake Mills's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Lake Mills's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Lake Mills's water compare to other cities in Wisconsin?
Lake Mills's water quality score of 0/100 earns a grade of F, which is considered failing. This is a concerning score that suggests significant water quality issues. Visit our Wisconsin state page to see how all cities in the state compare.
What should I do if I'm concerned about Lake Mills's water quality?
If you have concerns about Lake Mills's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (LAKE MILLS WATERWORKS) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.