Of the 3 Illinois lakes here with a published full pool, 1 is at or above full pool and 2 sit below it. The newest reading on this page is from September 24, 2026.
| Lake | Level now | Full pool | Against full pool | Reading |
|---|---|---|---|---|
| Carlyle Lake USACE St. Louis District | 444.96 ft | 445.00 ft | At full pool — on the high side for late September | September 24, 2026 |
| Lake Shelbyville USACE St. Louis District | 599.65 ft | 599.70 ft | 0.1 ft below full pool — typical for late September | September 24, 2026 |
| Rend Lake USACE St. Louis District | 404.13 ft | 405.00 ft | 0.9 ft below full pool — unusually low for late September | September 24, 2026 |
“Full pool” means the conservation pool — what that is, and what it is not. Lakes with no published figure are read against their own seasonal record instead.
Illinois lake levels, asked and answered
What are the lake levels in Illinois today?
Of the 3 Illinois lakes here with a published full pool, 1 is at or above full pool and 2 sit below it. The newest reading on this page is from September 24, 2026.
Which Illinois lake is furthest below full pool?
Rend Lake is the furthest down of the Illinois lakes on this page, at 0.9 ft below its full pool.
Where do these Illinois lake levels come from?
Each row is the gauge the agency that runs the lake publishes — the Corps of Engineers, the Bureau of Reclamation, the state water agency or the US Geological Survey, depending on the lake. Open a lake and its own page re-reads that gauge as the page loads, wherever the agency lets a browser do it.