Cudahy Waterworks, WI
Above the new 10 ppb level coming in 2027
Latest 90th-percentile lead: 13 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. Under the current 15 ppb rule this is not an exceedance, but it is above the 10 ppb action level that takes over in Nov 2027. Test your own tap; filter if your result shows lead.
Cudahy Waterworks at a glance
Cudahy Waterworks serves about 18,659 people through 6,910 service connections, which makes it a large system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws surface water, in Milwaukee County, Wisconsin. EPA system ID: WI2410169. Ask the utility on your bill for your address in their service line inventory.
Lead results over time
That is up 3 ppb from 10 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Cudahy Waterworks is 14 ppb across 5 monitoring periods, none of them over 15 ppb (3 over 10 ppb).
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 13 ppb over 10 |
| 2025 | 10 ppb |
| 2023 | 9 ppb |
| 2020 | 14 ppb over 10 |
| 2017 | 12 ppb over 10 |
How Cudahy Waterworks compares
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. Cudahy Waterworks's 13 ppb sits at the 99th percentile in Wisconsin and the 98th nationally (higher means more lead).
Nearby utilities
16 other systems share Milwaukee County; 0 of them have a higher latest lead result than Cudahy Waterworks. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Milwaukee Waterworks | 626,000 | 5.3 ppb |
| West Allis Waterworks | 63,240 | 2.4 ppb |
| Wauwatosa Waterworks | 49,064 | 8.4 ppb |
| North Shore Water Commission | 35,598 | 11 ppb |
| Oak Creek Waterworks | 32,104 | 2 ppb |
| Franklin Water Utility | 22,500 | 3 ppb |
| South Milwaukee Waterworks | 21,340 | 7.7 ppb |
| Greendale Waterworks | 14,393 | 0.32 ppb |
| Whitefish Bay Waterworks | 14,272 | 4.7 ppb |
| Shorewood Waterworks | 13,535 | 3.2 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Cudahy, 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 Cudahy 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. This system is in the band the 2027 10 ppb rule changes.