Lone Rock Waterworks, WI
Exceeded the action level in the past
Latest 90th-percentile lead: 1.11 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. 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.
Lone Rock Waterworks at a glance
Lone Rock Waterworks serves about 895 people through 267 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 Richland County, Wisconsin. EPA system ID: WI1530061. Ask the utility on your bill for your address in their service line inventory.
Lead results over time
That is up 1.11 ppb from 0 ppb in the period ending 2022. The highest 90th-percentile result EPA holds for Lone Rock Waterworks is 20 ppb across 6 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2023 | 1.11 ppb |
| 2022 | 0 (not detected) |
| 2021 | 2.48 ppb |
| 2021 | 7.4 ppb |
| 2020 | 20 ppb over 15 |
| 2017 | 13.1 ppb over 10 |
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. Lone Rock Waterworks's 1.11 ppb sits at the 45th percentile in Wisconsin and the 58th nationally (higher means more lead).
Neighbouring systems
6 other systems share Richland County; 4 of them have a higher latest lead result than Lone Rock Waterworks. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Richland Center Waterworks | 5,100 | 4.6 ppb |
| Sextonville Waterworks | 425 | 0.99 ppb |
| Cazenovia Waterworks | 351 | 0 (not detected) |
| Pine Valley Community Village | 225 | 6.03 ppb |
| Yuba Waterworks | 68 | 3.97 ppb |
| Acorn Acres Mhp | 52 | 152.75 ppb |
Next steps for Lone Rock, WI
Test your own tap with a certified lab first-draw sample; Lone Rock, 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 Lone Rock 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. What a 90th-percentile result does and does not tell you: how to read a lead result. Why an old exceedance still matters: over the limit before, under it now.