Glen Carbon, IL
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (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 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.
Glen Carbon at a glance
Glen Carbon serves about 12,618 people through 5,557 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 Madison County, Illinois. EPA system ID: IL1190300; phone on file: 618-288-2606. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Glen Carbon's lead record
That is down 1.2 ppb from 1.2 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Glen Carbon is 2.6 ppb across 9 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 0 (not detected) |
| 2025 | 1.2 ppb |
| 2024 | 2.3 ppb |
| 2023 | 2.6 ppb |
| 2022 | 1.8 ppb |
| 2022 | 1.5 ppb |
| 2021 | 1.6 ppb |
| 2019 | 1.8 ppb |
| 2018 | 0 (not detected) |
Against other Illinois systems
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. Glen Carbon's reported as 0 (not detected) sits at the 52nd percentile in Illinois and the 38th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Other water systems in Madison County
35 other systems share Madison County; 16 of them have a higher latest lead result than Glen Carbon. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Il American-Alton | 46,127 | 3 ppb |
| Il American-Granite City | 33,572 | 6 ppb |
| Collinsville | 30,616 | 0 (not detected) |
| Edwardsville | 26,808 | 0 (not detected) |
| Troy | 16,962 | 0 (not detected) |
| Bethalto | 15,210 | 1.2 ppb |
| Highland | 10,674 | 0 (not detected) |
| Wood River | 10,464 | 0 (not detected) |
| Maryville | 10,150 | 2 ppb |
| Fosterburg Pwd | 7,940 | 2.8 ppb |
What to do in your house
Look up your address in Glen Carbon'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 Glen Carbon 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. Small systems behave differently: why small systems go over more often.