Columbus Utilities, WI
Exceeded the action level in the past
Latest 90th-percentile lead: 8.88 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
Columbus Utilities serves about 5,173 people through 1,915 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 Columbia County, Wisconsin. EPA system ID: WI1110038. Ask the utility on your bill for your address in their service line inventory.
Columbus Utilities's lead record
That is down 1.32 ppb from 10.2 ppb in the period ending 2023. The highest 90th-percentile result EPA holds for Columbus Utilities is 21.3 ppb across 10 monitoring periods, 3 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 8.88 ppb |
| 2023 | 10.2 ppb over 10 |
| 2023 | 7.33 ppb |
| 2021 | 5.83 ppb |
| 2020 | 10 ppb |
| 2020 | 17.4 ppb over 15 |
| 2019 | 16.8 ppb over 15 |
| 2018 | 11.6 ppb over 10 |
| 2018 | 11.5 ppb over 10 |
| 2017 | 21.3 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. Columbus Utilities's 8.88 ppb sits at the 96th percentile in Wisconsin and the 96th nationally (higher means more lead).
Neighbouring systems
22 other systems share Columbia County; 1 of them has a higher latest lead result than Columbus Utilities. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Portage Waterworks | 10,437 | 6.2 ppb |
| Wisconsin Dells Waterworks | 3,232 | 1.7 ppb |
| Lodi Waterworks | 3,146 | 18 ppb |
| Poynette Waterworks | 2,520 | 3.05 ppb |
| Pardeeville Waterworks | 2,151 | 1.7 ppb |
| Harmony Grove San Dist | 1,950 | 3.2 ppb |
| Randolph Water Dept | 1,800 | 1.3 ppb |
| Fall River Waterworks | 1,793 | 0.93 ppb |
| Rio Waterworks | 1,095 | 1.4 ppb |
| Arlington Waterworks | 946 | 2 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Columbus, 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 Columbus Utilities 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. More in what a past exceedance means today.