Lakes / Illinois / Calhoun County / Watson Lake
Watson Lake, Illinois
353.61 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Illinois
39.07 degrees N, 90.68 degrees W - Calhoun County. State and county outlines drawn from Census boundary data; the lake marker is placed by its USGS National Hydrography Dataset coordinates, not by eye. Schematic - not a survey map.
How Watson Lake Stacks Up
- Larger than 84% of the 511 lakes counted in Illinois.
- The largest lake in Calhoun County among those counted.
- About 74 miles from Springfield, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Strator Pond | Calhoun | 4.5 mi | 177.67 acres |
| Middle Slough | Calhoun | 5.7 mi | 124.29 acres |
| Deep Lake | Jersey | 6.0 mi | 128.25 acres |
| Upper Stump Lake | Jersey | 7.5 mi | 840.65 acres |
| Lower Stump Lake | Calhoun | 9.2 mi | 182.12 acres |
| Godar Swamp | Calhoun | 11 mi | 78.33 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Watson Lake
How Big Is Watson Lake?
Watson Lake covers 353.61 acres in Calhoun County, Illinois.
What Is the Largest Lake in Calhoun County?
Watson Lake is the largest lake in Calhoun County, at 353.61 acres.
Largest Lakes in Illinois
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Carlyle Lake | Clinton | 22,796.77 acres | - |
| 2 | Mine Number 21 Reservoir | Franklin | 17,062.04 acres | - |
| 3 | Upper Peoria Lake | Woodford | 15,460.64 acres | - |
| 4 | Lake Shelbyville | Shelby | 10,235.1 acres | - |
| 5 | Crab Orchard Lake | Williamson | 7,292.57 acres | - |
All 511 Illinois lakes ranked by surface area
Sources: USGS National Hydrography Dataset (The National Map) lake data (ID 144571453). Verified October 30, 2026.