Marissa, IL
Lead detected, under the action levels
Latest 90th-percentile lead: 2.3 ppb (monitoring period 2024-2024). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. Lead was measured in sampled homes but the 90th percentile is under both action levels. EPA's health goal for lead is zero, so test your own tap if your home was built before 1986 or anyone in it is pregnant or a young child.
Who runs the water here
Marissa serves about 1,921 people through 895 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 surface water, in St. Clair County, Illinois. EPA system ID: IL1630750; phone on file: 618-295-2351. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
Against the period ending 2023 (2 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Marissa is 2.3 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 2.3 ppb |
| 2023 | 2 ppb |
| 2019 | 0 (not detected) |
| 2016 | 0 (not detected) |
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. Marissa's 2.3 ppb sits at the 75th percentile in Illinois and the 76th nationally (higher means more lead).
Nearby utilities
23 other systems share St. Clair County; 4 of them have a higher latest lead result than Marissa. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Il American-East St Louis | 131,368 | 3 ppb |
| O Fallon | 46,603 | 0 (not detected) |
| Caseyville | 13,798 | 0 (not detected) |
| Cahokia Heights | 12,528 | 0 (not detected) |
| Mascoutah | 8,759 | 4.9 ppb |
| American Water Oper And Maintenance, Llc | 6,779 | 0 (not detected) |
| Lebanon | 4,714 | 2.1 ppb |
| Freeburg | 4,707 | 1 ppb |
| Dupo | 4,684 | 0 (not detected) |
| Smithton | 4,381 | 0 (not detected) |
Next steps for Marissa, IL
Test your own tap with a certified lab first-draw sample; Marissa, 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 Marissa 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. Systems that went over once often dip back under; here is what that means.