Palatine, IL
Exceeded the action level in the past
Latest 90th-percentile lead: 8.9 ppb (monitoring period 2026-2026). 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
Palatine serves about 70,875 people through 19,483 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 Cook County, Illinois. EPA system ID: IL0312340; phone on file: 847-359-9031. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Palatine's lead record
That is up 8.9 ppb from 0 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Palatine is 16 ppb across 8 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 8.9 ppb |
| 2025 | 0 (not detected) |
| 2025 | 0 (not detected) |
| 2025 | 15 ppb over 10 |
| 2025 | 16 ppb over 15 |
| 2023 | 5.8 ppb |
| 2020 | 5.9 ppb |
| 2017 | 4.4 ppb |
Where this result ranks
Of the 1,744 Illinois systems with a lead result, the median latest reading is 0 ppb; 22 are over 15 ppb right now and 152 have gone over at some point. Palatine's 8.9 ppb sits at the 95th percentile in Illinois and the 96th nationally (higher means more lead).
Nearby utilities
154 other systems share Cook County; 18 of them have a higher latest lead result than Palatine. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Chicago | 2,721,308 | 6.4 ppb |
| Cicero | 83,000 | 5 ppb |
| Schaumburg | 75,750 | 0.87 ppb |
| Evanston | 74,486 | 6.5 ppb |
| Arlington Heights | 73,320 | 7.6 ppb |
| Skokie | 66,422 | 9.77 ppb |
| Des Plaines | 60,675 | 5.7 ppb |
| Oak Lawn | 58,362 | 9.3 ppb |
| Orland Park | 58,020 | 0 (not detected) |
| Berwyn | 57,250 | 2.35 ppb |
Next steps for Palatine, IL
Test your own tap with a certified lab first-draw sample; Palatine, IL 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 Palatine 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. The lead result guide covers how utilities pick the homes they sample. More in what a past exceedance means today.