Prophetstown, 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 Prophetstown
Prophetstown serves about 1,946 people through 955 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 Whiteside County, Illinois. EPA system ID: IL1950400; phone on file: 815-537-5598. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Every lead result on file
That is down 8.2 ppb from 8.2 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Prophetstown is 8.2 ppb across 7 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 0 (not detected) |
| 2025 | 8.2 ppb |
| 2025 | 0 (not detected) |
| 2024 | 0 (not detected) |
| 2023 | 0 (not detected) |
| 2020 | 1.79 ppb |
| 2017 | 3.31 ppb |
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. Prophetstown's reported as 0 (not detected) sits at the 40th percentile in Illinois and the 30th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Other water systems in Whiteside County
10 other systems share Whiteside County; 4 of them have a higher latest lead result than Prophetstown. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Il American-Sterling | 14,782 | 0 (not detected) |
| Rock Falls | 8,620 | 3.1 ppb |
| Morrison | 4,188 | 4.6 ppb |
| Fulton | 3,346 | 0 (not detected) |
| Erie | 1,479 | 1.2 ppb |
| Albany | 846 | 1.6 ppb |
| Tampico | 689 | 0 (not detected) |
| Lyndon | 537 | 0 (not detected) |
| Country Acres Mhp (Whiteside County) | 232 | 0 (not detected) |
| Honeycutt Hill Mhp Llc | 75 | 0 (not detected) |
Next steps for Prophetstown, IL
Look up your address in Prophetstown'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 Prophetstown 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. A zero today does not rule out a jump later - the rules are tightening in 2027.