Lake Mills Municipal Water Dept-South, IA
Lead detected, under the action levels
Latest 90th-percentile lead: 3 ppb (monitoring period 2023-2025). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. Lead was measured in sampled homes but the 90th percentile is under both action levels. EPA's health goal for lead is zero, so test your own tap if your home was built before 1986 or anyone in it is pregnant or a young child.
Lake Mills Municipal Water Dept-South at a glance
Lake Mills Municipal Water Dept-South serves about 2,158 people through 1,116 service connections, which makes it a small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Winnebago County, Iowa. EPA system ID: IA9545044; phone on file: 641-590-2784. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Lead results over time
That is down 4 ppb from 7 ppb in the period ending 2022. The highest 90th-percentile result EPA holds for Lake Mills Municipal Water Dept-South is 7 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 3 ppb |
| 2022 | 7 ppb |
| 2019 | 7 ppb |
| 2016 | 5 ppb |
Where this result ranks
Of the 1,066 Iowa systems with a lead result, the median latest reading is 1.4 ppb; 4 are over 15 ppb right now and 36 have gone over at some point. Lake Mills Municipal Water Dept-South's 3 ppb sits at the 76th percentile in Iowa and the 82nd nationally (higher means more lead).
Nearby utilities
6 other systems share Winnebago County; 2 of them have a higher latest lead result than Lake Mills Municipal Water Dept-South. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Forest City Water Supply | 4,285 | 5 ppb |
| Buffalo Center Muni Water Dept | 857 | 0 (not detected) |
| Thompson Water Works | 499 | 0 (not detected) |
| Leland Water Supply | 249 | 9.8 ppb |
| Rake Water Supply | 186 | 1 ppb |
| Rocky Knoll Mhp | 49 | 0 (not detected) |
Your move
Test your own tap with a certified lab first-draw sample; Lake Mills, IA may offer free or low-cost kits through the utility. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Lake Mills Municipal Water Dept-South whether it covers that cost before hiring anyone - many utilities now do.
These figures describe homes the utility sampled, not your tap. Only your service line record or a test of your own water answers the question for your house. What a 90th-percentile result does and does not tell you: how to read a lead result. Size matters more than most people expect: small vs large water systems.