Mosinee Waterworks, WI
Lead detected, under the action levels
Latest 90th-percentile lead: 2.2 ppb (monitoring period 2023-2023). 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.
About Mosinee Waterworks
Mosinee Waterworks serves about 3,406 people through 1,783 service connections, which makes it a medium-sized system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Marathon County, Wisconsin. EPA system ID: WI7370159. Ask the utility on your bill for your address in their service line inventory.
Lead results over time
That is up 1.41 ppb from 0.79 ppb in the period ending 2020. The highest 90th-percentile result EPA holds for Mosinee Waterworks is 10 ppb across 8 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2023 | 2.2 ppb |
| 2020 | 0.79 ppb |
| 2019 | 3.8 ppb |
| 2018 | 5.9 ppb |
| 2017 | 4.7 ppb |
| 2017 | 9.3 ppb |
| 2016 | 10 ppb |
| 2016 | 8.8 ppb |
Where this result ranks
Of the 947 Wisconsin systems with a lead result, the median latest reading is 1.33 ppb; 6 are over 15 ppb right now and 71 have gone over at some point. Mosinee Waterworks's 2.2 ppb sits at the 66th percentile in Wisconsin and the 75th nationally (higher means more lead).
Other water systems in Marathon County
22 other systems share Marathon County; 10 of them have a higher latest lead result than Mosinee Waterworks. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Wausau Waterworks | 39,994 | 5.8 ppb |
| Weston Municipal Utilities | 16,000 | 0.75 ppb |
| Kronenwetter Water & Sewer Utility | 6,931 | 0.76 ppb |
| Rib Mountain Water Utility | 6,398 | 2.4 ppb |
| Rothschild Waterworks | 3,190 | 7.3 ppb |
| Abbotsford Waterworks | 2,502 | 3.5 ppb |
| Schofield Waterworks | 2,205 | 0 (not detected) |
| Spencer Waterworks | 1,848 | 0.8 ppb |
| Colby Waterworks | 1,829 | 0.95 ppb |
| Marathon City Waterworks | 1,695 | 0.36 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Mosinee, WI 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 Mosinee Waterworks whether it covers that cost before hiring anyone - many utilities now do. Its latest copper 90th percentile is 1400 ppb (copper action level 1,300 ppb).
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. Why sampled homes are the worst-case ones is in the guide to reading the number. Size matters more than most people expect: small vs large water systems.