Lakes / Oklahoma / Custer County / Foss Reservoir
Foss Reservoir, Oklahoma
6,380.7 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Oklahoma
35.58 degrees N, 99.22 degrees W - Custer 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 Foss Reservoir Stacks Up
- Larger than 94% of the 376 lakes counted in Oklahoma.
- The largest lake in Custer County among those counted.
- About 82 miles from Lawton, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Soldier Creek Watershed Site 5 Reservoir | Custer | 6.6 mi | 49.67 acres |
| Turkey Creek Site 6 Reservoir | Washita | 9.6 mi | 95.52 acres |
| Soldier Creek Watershed Site 4 Reservoir | Washita | 9.8 mi | 74.13 acres |
| Clinton Lake | Washita | 9.9 mi | 260.84 acres |
| Turkey Creek Site 9 Reservoir | Washita | 11 mi | 27.68 acres |
| Turkey Creek Site 7 Reservoir | Washita | 11 mi | 49.42 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Foss Reservoir
How Big Is Foss Reservoir?
Foss Reservoir covers 6,380.7 acres in Custer County, Oklahoma.
What Is the Largest Lake in Custer County?
Foss Reservoir is the largest lake in Custer County, at 6,380.7 acres.
Largest Lakes in Oklahoma
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Eufaula Lake | Pittsburg | 100,734.12 acres | - |
| 2 | Lake Texoma | Marshall | 59,414.43 acres | - |
| 3 | Grand Lake O' The Cherokees | Delaware | 38,902.36 acres | - |
| 4 | Robert S Kerr Reservoir | Haskell | 35,795.91 acres | - |
| 5 | Oologah Lake | Rogers | 29,728.7 acres | - |
All 376 Oklahoma lakes ranked by surface area
Sources: USGS National Hydrography Dataset (The National Map) lake data (ID 125344675). Verified October 30, 2026.