Denmark Waterworks, WI
Lead detected, under the action levels
Latest 90th-percentile lead: 0.68 ppb (monitoring period 2025-2025). 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.
Denmark Waterworks at a glance
Denmark Waterworks serves about 2,684 people through 976 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 surface water, in Brown County, Wisconsin. EPA system ID: WI4050351. Ask the utility on your bill for your address in their service line inventory.
Every lead result on file
Against the period ending 2024 (0.72 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Denmark Waterworks is 3.3 ppb across 12 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 0.68 ppb |
| 2024 | 0.72 ppb |
| 2023 | 1.3 ppb |
| 2023 | 0.91 ppb |
| 2022 | 2.5 ppb |
| 2020 | 0.97 ppb |
| 2020 | 3.3 ppb |
| 2019 | 2.2 ppb |
| 2019 | 3 ppb |
| 2018 | 1.4 ppb |
| 2018 | 1.6 ppb |
| 2017 | 1.6 ppb |
Against other Wisconsin systems
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. Denmark Waterworks's 0.68 ppb sits at the 31st percentile in Wisconsin and the 46th nationally (higher means more lead).
Neighbouring systems
21 other systems share Brown County; 13 of them have a higher latest lead result than Denmark Waterworks. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Green Bay Waterworks | 107,369 | 2.5 ppb |
| De Pere Waterworks Sa 1 | 25,660 | 0.66 ppb |
| Howard Waterworks | 21,133 | 1.2 ppb |
| Ashwaubenon Waterworks | 17,730 | 3.4 ppb |
| Bellevue Waterworks | 16,715 | 2.7 ppb |
| Allouez Waterworks | 13,923 | 5.9 ppb |
| Ledgeview Tn Sanitary Dist 2 | 7,602 | 2.1 ppb |
| Lawrence Waterworks | 5,398 | 0 (not detected) |
| Suamico Waterworks | 4,697 | 1.1 ppb |
| Pulaski Waterworks | 4,040 | 0.81 ppb |
Next steps for Denmark, WI
Test your own tap with a certified lab first-draw sample; Denmark, 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 Denmark Waterworks whether it covers that cost before hiring anyone - many utilities now do. Its latest copper 90th percentile is 1500 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. The action level is dropping - the 10 ppb rule from 2027.