Matherville, IL
Above the new 10 ppb level coming in 2027
Latest 90th-percentile lead: 11.6 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.
Matherville at a glance
Matherville serves about 651 people through 308 service connections, which makes it a small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Mercer County, Illinois. EPA system ID: IL1310200; phone on file: 309-373-5856. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Lead results over time
That is up 10.4 ppb from 1.2 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Matherville is 11.6 ppb across 5 monitoring periods, none of them over 15 ppb (1 over 10 ppb).
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 11.6 ppb over 10 |
| 2025 | 1.2 ppb |
| 2022 | 1.2 ppb |
| 2019 | 1.1 ppb |
| 2016 | 1.7 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. Matherville's 11.6 ppb sits at the 97th percentile in Illinois and the 98th nationally (higher means more lead).
Nearby utilities
13 other systems share Mercer County; 0 of them have a higher latest lead result than Matherville. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Aledo | 3,470 | 3 ppb |
| Viola | 869 | 0 (not detected) |
| Sherrard | 785 | 1.9 ppb |
| Fyre Lake Water Company | 760 | 2.2 ppb |
| Keithsburg | 747 | 0 (not detected) |
| New Windsor | 740 | 6.2 ppb |
| New Boston | 613 | 0 (not detected) |
| Forrest Brooke Mhp | 491 | - |
| Joy | 377 | 1.7 ppb |
| North Henderson | 172 | 1.3 ppb |
Next steps for Matherville, IL
Test your own tap with a certified lab first-draw sample; Matherville, 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 Matherville 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. This system is in the band the 2027 10 ppb rule changes.