Lakes / South Dakota / Marshall County / Simmon Lake
Simmon Lake, South Dakota
67.21 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - South Dakota
45.72 degrees N, 97.34 degrees W - Marshall 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 Simmon Lake Stacks Up
- Larger than 26% of the 533 lakes counted in South Dakota.
- About 58 miles from Watertown, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Goodbird Lake | Marshall | 1.6 mi | 66.47 acres |
| Crystal Lake | Marshall | 1.8 mi | 74.13 acres |
| Long Lake | Marshall | 1.9 mi | 289.85 acres |
| Clear Lake | Marshall | 2.0 mi | 1,198.96 acres |
| North Red Iron Lake | Marshall | 2.2 mi | 175.2 acres |
| Turtlefoot Lake | Marshall | 2.7 mi | 122.32 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Simmon Lake
How Big Is Simmon Lake?
Simmon Lake covers 67.21 acres in Marshall County, South Dakota.
What Is the Largest Lake in Marshall County?
Buffalo Lakes is the largest lake in Marshall County, at 1,986.48 acres.
Largest Lakes in South Dakota
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Lake Oahe | Dewey | 309,912.57 acres | - |
| 2 | Lake Francis Case | Charles Mix | 82,166.92 acres | - |
| 3 | Lake Sharpe | Hughes | 58,419.67 acres | - |
| 4 | Lewis and Clark Lake | Bon Homme | 25,141.99 acres | - |
| 5 | Lake Thompson | Kingsbury | 13,887.93 acres | - |
All 533 South Dakota lakes ranked by surface area
Sources: USGS National Hydrography Dataset (The National Map) lake data (ID 145086953). Verified October 30, 2026.