Deuel County ( ) is a county in the U.S. state of South Dakota. As of the 2020 census, the population was 4,295. Its county seat is Clear Lake. The county was created in 1862, and was organized in 1878. It is named for Jacob Deuel, a legislator in 1862.
Geography
thumb|right|Soils of Deuel County
Deuel County lies on the east boundary line of South Dakota. Its east boundary line abuts the west boundary line of the state of Minnesota. Its terrain consists of rolling hills, sloped to the northeast. The area is largely devoted to agriculture. The county's highest elevation occurs on its upper west boundary line, at ASL. The county has a total area of , of which is land and (2.2%) is water.
Major highways
- 20px Interstate 29
- 23px U.S. Highway 212
- 20px South Dakota Highway 15
- 20px South Dakota Highway 22
- 20px South Dakota Highway 28
- 23px South Dakota Highway 101
Adjacent counties
- Grant County – north
- Lac qui Parle County, Minnesota – northeast
- Yellow Medicine County, Minnesota – east
- Lincoln County, Minnesota – southeast
- Brookings County – south
- Hamlin County – southwest
- Codington County – northwest
Lakes
- Bullhead Lake
- Briggs Lake
- Clear Lake
- East Coteau Lake
- Fish Lake
- Fox Lake
- Lake Alice
- Lake Cochrane
- Lake Francis
- Lake Ketchum
- Lake Oliver
- Lake Milk
- Lone Tree Lake
- North Coteau Lake
- Round Lake
- Rush Lake
- Salt Lake (part)
- School Lake
- Slough Up’Nort
- South Coteau Lake
- Wigdale Lake
Protected areas
- Altamont State Public Shooting Area
- Astoria State Wildlife Management Area
- Briggs Lake State Public Shooting Area
- Crystal Springs State Public Shooting Area
- Lake Cochrane State Recreation Area
- Lake Francis State Public Shooting Area
- Lone Tree Lake State Public Shooting Area
- Mitchell State Public Shooting Area
- Mud Lake State Public Shooting Area
- Nelson State Wildlife Management Area
- Rome State Wildlife Management Area
- Round Lake State Wildlife Management Area
- Runge State Wildlife Management Area
- Rush Lake State Public Shooting Area
- Sharp State Public Shooting Area
- Singsaas Slough State Wildlife Management Area
- Sokota State Wildlife Management Area (partial)