Cobb Waterworks, WI
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (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 90th-percentile result was reported as 0 (not detected at the lab's limit). That says the sampled homes were low, not that your home has no lead service line. Check your utility's service line inventory for your address.
About Cobb Waterworks
Cobb Waterworks serves about 458 people through 169 service connections, which makes it a very small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Iowa County, Wisconsin. EPA system ID: WI1250076. Ask the utility on your bill for your address in their service line inventory.
Every lead result on file
That is down 2.78 ppb from 2.78 ppb in the period ending 2020. The highest 90th-percentile result EPA holds for Cobb Waterworks is 2.78 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2023 | 0 (not detected) |
| 2020 | 2.78 ppb |
| 2017 | 0.98 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. Cobb Waterworks's reported as 0 (not detected) sits at the 10th percentile in Wisconsin and the 22nd nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Nearby utilities
14 other systems share Iowa County; 9 of them have a higher latest lead result than Cobb Waterworks. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Dodgeville Waterworks | 4,583 | 1.4 ppb |
| Mineral Point Waterworks | 2,487 | 37 ppb |
| Barneveld Waterworks | 1,258 | 1.9 ppb |
| Arena Waterworks | 877 | 1.1 ppb |
| Highland Waterworks | 842 | 0 (not detected) |
| Ridgeway Waterworks | 690 | 3.48 ppb |
| Linden Waterworks | 547 | 2.2 ppb |
| Avoca Waterworks | 545 | 0 (not detected) |
| House On The Rock Resort | 470 | 1.78 ppb |
| Rewey Waterworks | 290 | 0 (not detected) |
Next steps for Cobb, WI
Look up your address in Cobb Waterworks's service line inventory. If it says lead, galvanized or unknown, test your tap. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Cobb 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. A zero today does not rule out a jump later - the rules are tightening in 2027.