Lake Mills, WI · PWSID WI1280108
Lake Mills Waterworks lead service lines
152 lead or galvanized lines to replace
Lake Mills Waterworks reported 143 lead and 9 galvanized-requiring-replacement service lines out of 2,220 in its inventory. That's about 1 in 15 lines. Another 5 (0.2%) are still listed as unknown material.
Ranks #63 of 258 Wisconsin systems with confirmed lead lines, and #1,475 nationally.
6.8% of Lake Mills Waterworks's service lines are lead or galvanized requiring replacement. That's lower than the Wisconsin average (11%) and higher than the national average (3.1%).
- Lead 6.4%
- Galvanized (replace) 0.4%
- Unknown 0.2%
- Non-lead 93%
Total service lines reported: 2,220. Reported all required service line types. Population served: 6,211; 2,607 connections.
Lead test results
Lake Mills Waterworks's most recent 90th-percentile lead result (Jun 2025–Sep 2025) was 4.6 ppb, below both the 15 ppb action level and the 10 ppb level that takes effect in 2027. This means 90% of homes sampled were at or below that level; individual homes, especially those with lead lines, can be higher.
Lead and Copper Rule 90th-percentile results reported to EPA, in parts per billion. Dashed lines: 15 ppb action level and the 10 ppb level from November 1, 2027.
Progress since 2025 Q1
Reported lead and galvanized-requiring-replacement lines went from 152 in 2025 Q1 to 152 in 2026 Q3: no change. Lines of unknown material went from 6 to 5, down 1 (17%).
Quarterly counts reported to EPA. A drop usually means lines were replaced or confirmed non-lead; a rise usually means more lines were identified. Replacement progress rankings.
Lead rule violations
EPA's data lists 17 Lead and Copper Rule violations since 2015, 5 health-based, 1 still open for Lake Mills Waterworks. Health-based violations are treatment failures, such as corrosion control or public education; the rest are missed monitoring or reporting.
| Began | Violation | Status |
|---|---|---|
| Sep 2022 | Corrosion control treatment not installed or operated health-based | Returned to compliance |
| Oct 2017 | Corrosion control study or recommendation not done health-based | Returned to compliance |
| Jul 2017 | Missed follow-up or routine lead and copper tap sampling | Returned to compliance |
| Apr 2017 | Lead consumer notice not delivered or reported | Returned to compliance |
| Jan 2017 | Missed water quality parameter monitoring | Returned to compliance |
| Jan 2017 | Missed water quality parameter monitoring | Returned to compliance |
| Jan 2017 | Missed water quality parameter monitoring | Returned to compliance |
| Jan 2017 | Missed water quality parameter monitoring | Returned to compliance |
| Jan 2017 | Missed source water monitoring | Returned to compliance |
| Jan 2017 | Missed source water monitoring | Returned to compliance |
Source: EPA SDWIS violation records for the Lead and Copper Rule.
Where the water comes from
Lake Mills Waterworks's main water source is groundwater (wells).
Source: EPA SDWIS water system and facility records.
Check your own address
These counts cover the whole system. To see whether your line is lead, use the utility's address-level inventory. Utilities had to prepare one by October 16, 2024 and make it publicly accessible; systems serving more than 50,000 people must post it online.
No map yet? Do the 2-minute scratch and magnet test on the pipe where water enters your home.
Protect your drinking water now
If your line is lead, galvanized or unknown, filter water for drinking, cooking and baby formula. Use a filter certified to NSF/ANSI 53 for lead. Run cold water for a few minutes after it sits for hours, and never use hot tap water for cooking.
How to pick a lead-certified filter · How to test your water for lead
Getting the line replaced
EPA's Lead and Copper Rule Improvements require most systems to replace lead and galvanized-requiring-replacement lines by December 31, 2037. Ask Lake Mills Waterworks whether it replaces the private side for free or with a cost share before you hire anyone. If you want it done sooner, or your utility doesn't cover your side, a licensed plumber can quote it. What replacement costs.
County pages: Lead pipes in Jefferson County
ZIP codes served
ZIP codes whose center falls inside Lake Mills Waterworks's mapped service area (EPA service area boundaries). Neighboring utilities may serve parts of the same ZIP.
53551
Other water systems nearby
| System | Lead + galv. | Unknown |
|---|---|---|
| Watertown Waterworks | 934 | 1 |
| Fort Atkinson Waterworks | 788 | 46 |
| Jefferson Waterworks | 335 | 0 |
| Johnson Creek Waterworks | 11 | 37 |
| Palmyra Waterworks | 63 | 449 |
| Tremain Mobile Home Park | 0 | 182 |
| Breezy Knoll Community | 0 | 50 |
| Ripview Court 1 | 0 | 18 |
Check another water system
Questions
Does Lake Mills Waterworks have lead pipes?
Yes. Lake Mills Waterworks reported 143 lead service lines and 9 galvanized lines that must be replaced, out of 2,220 total. 5 more are of unknown material.
How do I check if my home's service line is lead?
Look up your address on Lake Mills Waterworks's official service line inventory, which utilities must make publicly available. You can also scratch the pipe where it enters your home: lead is soft, dull gray, scratches to shiny silver and does not attract a magnet.
When will Lake Mills Waterworks replace lead service lines?
Under EPA's Lead and Copper Rule Improvements, most systems must replace lead and galvanized-requiring-replacement lines by December 31, 2037, starting from November 1, 2027. The rule is being challenged in court, so dates could change. Many utilities run free or cost-share programs now.
Has Lake Mills Waterworks had lead violations?
EPA's data shows 17 Lead and Copper Rule violations since 2015, 5 health-based, 1 still open for Lake Mills Waterworks.
Which water filters remove lead?
Use a filter certified to NSF/ANSI Standard 53 for lead reduction, or NSF/ANSI 58 for reverse osmosis. Check the certification on NSF's listings, not just the box.
Embed or cite this data
Local news sites, blogs and community groups can embed this card. It updates when EPA releases new data.
Citation: Lead Pipe Map, "Lake Mills Waterworks lead service lines," https://leadpipemap.com/wi/lake-mills-waterworks/. Source: EPA SDWIS service line inventory, 2026 Q3. Download the full dataset on the data page.