According to the 2020 population data released by the United States Census Bureau Thursday, the last decade saw exactly half of South Dakota’s counties gain population and exactly half lose population:
South Dakota’s even split between counties gaining people and counties losing people is a little better than the national split: 47% of counties in the United States grew in population over the last decade.
The 33 counties that lost population—mostly in the middle, with an arm of shrinkage reaching out interestingly east through every county on Highway 34—counted 4,871 people in 2020 than in 2010. Our three largest counties and the three biggest gainers numerically—Minnehaha, Pennington, and Lincoln—each added many more people than the loss from those 33 counties. The 33 growing counties added 77,358 people, almost sixteen times the loss from the shrinking half of the state.
Six counties accounted for 90.49% (65,593 people) of our net statewide population growth of 72,487: Minnehaha, Lincoln, Pennington, Meade, Union, and Brookings. That’s mostly town people in Sioux Falls and the suburbs it’s swallowing to the south, Rapid City and its I-90 flanks, Brookings, and the Iowa commuters from Sioux City settling west of the Big Sioux.
The biggest county that shrank was Lake. My impression was that Lake County and its county seat of Madison were growing. The Census Bureau thought so, too, projecting last year that Madison was going to see possibly 13% growth, booming to well over 7,000. But the official count shows Madison shrank 4.4%, from 6,474 in 2010 to 6,191 last year, a loss of 283 people. Folks must have moved out to the lakes: Lake County as a whole shrank 1.26%, losing 141 people.
Lake County was the only county with a population over 10,000 that lost people. The other 32 counties that shrank started the decade with four-figure populations and just got smaller. Jones County, home of Murdo, Draper, Okaton, and Capa, is the only county in South Dakota with fewer than 1,000 people—they lost 89 people, 8.85% of their 2010 population, to end up at 917.
Jones was not the biggest loser by number or percentage. Faulk (Faulkton), Hyde (Highmore), Ziebach (Dupree), and Jerauld (Wessington Springs) all saw population declines of double-digit percentages. Jerauld saw the largest decline by percentage and number: the Census counted 408 fewer people in and around Wessington Springs in 2020 than in 2010, a 19.7% decline.
The 33 counties that lost population make up less than 15% of South Dakota’s 2020 population. 64% of South Dakotans now live in our ten largest counties.