Northern Illinois University-Dekalb, 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.
About Northern Illinois University-Dekalb
Northern Illinois University-Dekalb serves about 6,500 people through 70 service connections, which makes it a medium-sized system under EPA's size classes. It is owned by the state and draws groundwater, in Dekalb County, Illinois. EPA system ID: IL0375500; phone on file: 815-753-0388. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
That is down 6.87 ppb from 6.87 ppb in the period ending 2024. The highest 90th-percentile result EPA holds for Northern Illinois University-Dekalb is 6.87 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 0 (not detected) |
| 2024 | 6.87 ppb |
| 2021 | 6.3 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. Northern Illinois University-Dekalb's reported as 0 (not detected) sits at the 49th percentile in Illinois and the 36th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Nearby utilities
19 other systems share Dekalb County; 8 of them have a higher latest lead result than Northern Illinois University-Dekalb. 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 |
| Genoa | 5,298 | 6.3 ppb |
| 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) |
What to do in your house
Look up your address in Northern Illinois University-Dekalb'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 Northern Illinois University-Dekalb 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. A zero today does not rule out a jump later - the rules are tightening in 2027.