Lakes / Illinois / Macoupin County / Otter Lake
Otter Lake, Macoupin County, Illinois
419.34 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Illinois
39.42 degrees N, 89.90 degrees W - Macoupin 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 Otter Lake Stacks Up
- Larger than 85% of the 511 lakes counted in Illinois.
- The largest lake in Macoupin County among those counted.
- About 28 miles from Springfield, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Sunset Lake | Macoupin | 3.0 mi | 123.31 acres |
| Palmyra-Modesto City Lake | Macoupin | 3.6 mi | 36.57 acres |
| Standard City Lake | Macoupin | 8.3 mi | 41.91 acres |
| Bunn Lake | Macoupin | 8.8 mi | 78.33 acres |
| Lake Carlinville | Macoupin | 13 mi | 155.92 acres |
| Smith Reservoir | Macoupin | 14 mi | 63.75 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Otter Lake
How Big Is Otter Lake?
Otter Lake covers 419.34 acres in Macoupin County, Illinois.
What Is the Largest Lake in Macoupin County?
Otter Lake is the largest lake in Macoupin County, at 419.34 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 154287072). Verified October 30, 2026.