Edgerton Waterworks, WI
Exceeded the action level in the past
Latest 90th-percentile lead: 2.76 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. The latest result is under the action level, but this system has gone over 15 ppb before. Lead comes from pipes, not the source water, so a home with a lead service line can still be exposed. Test your own tap.
Who runs the water here
Edgerton Waterworks serves about 5,512 people through 2,041 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 Rock County, Wisconsin. EPA system ID: WI1540119. Ask the utility on your bill for your address in their service line inventory.
Lead results over time
That is down 8.24 ppb from 11 ppb in the period ending 2023. The highest 90th-percentile result EPA holds for Edgerton Waterworks is 20.7 ppb across 8 monitoring periods, 3 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 2.76 ppb |
| 2023 | 11 ppb over 10 |
| 2023 | 9.66 ppb |
| 2019 | 16.3 ppb over 15 |
| 2019 | 12.1 ppb over 10 |
| 2018 | 15.6 ppb over 15 |
| 2018 | 9.74 ppb |
| 2017 | 20.7 ppb over 15 |
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. Edgerton Waterworks's 2.76 ppb sits at the 72nd percentile in Wisconsin and the 79th nationally (higher means more lead).
Neighbouring systems
17 other systems share Rock County; 3 of them have a higher latest lead result than Edgerton Waterworks. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Janesville Water Utility | 64,415 | 2.4 ppb |
| Beloit City Of | 36,677 | 4.5 ppb |
| Evansville Waterworks | 5,703 | 6.33 ppb |
| Milton Waterworks | 5,588 | 1.47 ppb |
| Clinton Waterworks | 2,119 | 0.29 ppb |
| Orfordville Waterworks | 1,475 | 0.68 ppb |
| Footville Waterworks | 816 | 0 (not detected) |
| Rock River Leisure Estates Coop | 650 | 0.87 ppb |
| Caravilla Education And Rehab Center | 298 | 0 (not detected) |
| County Line Estates | 240 | 0.15 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Edgerton, 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 Edgerton Waterworks 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. Why sampled homes are the worst-case ones is in the guide to reading the number. Why an old exceedance still matters: over the limit before, under it now.