Lakes / Ohio / O'Shaughnessy Reservoir
O'Shaughnessy Reservoir, Ohio
896 acres
Surface Area
40 ft
Max Depth
19.13 mi
Shoreline
857 ft
Surface Elevation
Where It Sits, and How Deep It Goes
Locator - Ohio
40.19 degrees N, 83.14 degrees W - Delaware County. State and county outlines drawn from Census boundary data; the lake marker is placed by its Ohio DNR coordinates, not by eye. Schematic - not a survey map.
Depth Profile - O'Shaughnessy Reservoir
Schematic cross-section drawn to one shared depth scale - not a survey or bathymetric map.
Facts and Figures
Waterbody IDoh-o-shaughnessy-reservoir-39041
CountyDelaware
Shoreline19.13 mi
Coordinates40.1938, -83.1358
Deepest Natural Lakes in Ohio
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | McKarns Lake | Williams | 40 acres | 75 ft |
| 2 | Portage Lakes | Summit | 474 acres | 60 ft |
| 3 | Punderson Lake | Geauga | 80 acres | 55 ft |
| 4 | Wolf Run Lake | Noble | 208 acres | 51 ft |
| 5 | Barton Lake | Williams | 19 acres | 42 ft |
Largest Lakes in Ohio
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Grand Lake St. Marys | Mercer | 13,356 acres | 14 ft |
| 2 | Mosquito Creek Lake | Trumbull | 7,212 acres | 24 ft |
| 3 | Indian Lake | Logan | 5,161 acres | 12 ft |
| 4 | Seneca Lake | Noble | 3,550 acres | 21 ft |
| 5 | Berlin Lake | Portage | 3,344 acres | 60 ft |
Sources: Ohio Department of Natural Resources lake data (ID oh-o-shaughnessy-reservoir-39041); USGS. Verified October 28, 2026.