Codington County is a county in the U.S. state of South Dakota. As of the 2020 census, the population was 28,325, making it the 7th most populous county in South Dakota. Its county seat is Watertown. The county was created in 1877 and organized in 1878. It is named for Rev. George S. S. Codington, Dakota Territory legislator. Codington County comprises the Watertown, SD Micropolitan Statistical Area.

Geography

Codington County terrain consists of rolling hills dotted with lakes and ponds, especially in the southwest portion. The land is largely devoted to agriculture. The terrain is higher on the county's east and west sides, and generally slopes to the south. The county has a total area of 717 sqmi, of which 688 sqmi is land and 29 sqmi (4.0%) is water.

Major highways

Transit

Adjacent counties

Protected areas

Major lakes

Demographics

2020 census

As of the 2020 census, there were 28,325 people, 12,026 households, and 7,199 families residing in the county. The population density was 41.2 PD/sqmi. There were 13,211 housing units.

2010 census

As of the 2010 census, there were 27,227 people, 11,432 households, and 7,216 families in the county. The population density was 39.5 PD/sqmi. There were 12,397 housing units at an average density of 18.0 /sqmi. The racial makeup of the county was 95.3% white, 2.0% American Indian, 0.4% Asian, 0.3% black or African American, 0.6% from other races, and 1.3% from two or more races. Those of Hispanic or Latino origin made up 1.6% of the population. In terms of ancestry, 54.3% were German, 22.6% were Norwegian, 9.6% were Irish, 6.7% were English, and 3.3% were American. Of the 11,432 households, 30.7% had children under the age of 18 living with them, 49.9% were married couples living together, 9.0% had a female householder with no husband present, 36.9% were non-families, and 30.6% of all households were made up of individuals. The average household size was 2.35 and the average family size was 2.93. The median age was 37.7 years. The median income for a household in the county was $43,275 and the median income for a family was $60,202. Males had a median income of $39,076 versus $26,945 for females. The per capita income for the county was $24,781. About 8.9% of families and 12.7% of the population were below the poverty line, including 13.7% of those under age 18 and 16.8% of those age 65 or over.

Communities

City

Towns

Census-designated place

Unincorporated communities

Townships

Politics

Codington County voters have been reliably Republican for several decades. In no national election since 1976 has the county selected the Democratic Party candidate.