Genoa, IL
Lead detected, under the action levels
Latest 90th-percentile lead: 6.3 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. 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
Genoa serves about 5,298 people through 2,060 service connections, which makes it a medium-sized system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Dekalb County, Illinois. EPA system ID: IL0370150; phone on file: 815-784-7131. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Lead results over time
That is down 2.4 ppb from 8.7 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Genoa is 10 ppb across 8 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 6.3 ppb |
| 2025 | 8.7 ppb |
| 2025 | 4.2 ppb |
| 2025 | 0 (not detected) |
| 2025 | 10 ppb |
| 2023 | 6.7 ppb |
| 2020 | 5.6 ppb |
| 2017 | 8.3 ppb |
How Genoa compares
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. Genoa's 6.3 ppb sits at the 91st percentile in Illinois and the 94th nationally (higher means more lead).
Neighbouring systems
19 other systems share Dekalb County; 3 of them have a higher latest lead result than Genoa. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Dekalb | 40,290 | 13 ppb |
| Sycamore | 18,500 | 0 (not detected) |
| Sandwich | 7,156 | 2 ppb |
| Northern Illinois University-Dekalb | 6,500 | 0 (not detected) |
| Cortland | 4,398 | 0 (not detected) |
| Hinckley | 2,006 | 0 (not detected) |
| Somonauk | 1,860 | 0 (not detected) |
| Kirkland | 1,650 | 0 (not detected) |
| Waterman | 1,497 | 8.77 ppb |
| Kingston | 1,160 | 0 (not detected) |
Next steps for Genoa, IL
Test your own tap with a certified lab first-draw sample; Genoa, 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 Genoa 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. The action level is dropping - the 10 ppb rule from 2027.