South Dakota State House District 31

State Legislative District Profile (Lower Chamber)

Overview

District ID
sd-hd-031
State
South Dakota
Chamber
Lower chamber
District Code
031
Land Area
800.1 sq mi
Water Area
0.26 sq mi

Boundary

Boundary of South Dakota State House District 31

Boundary as GeoJSON

Source: U.S. Census Bureau TIGER/Line state legislative district boundaries.

Counties

CountyOverlapShare of district landShare of county land
Lawrence County800.05 sq mi100.0%100.0%

Showing all 1 county

Places

PlaceOverlapShare of district landShare of place land
Spearfish city16.75 sq mi2.1%97.0%
Deadwood city4.93 sq mi0.6%100.0%
North Spearfish CDP4.28 sq mi0.5%100.0%
Boulder Canyon CDP3.06 sq mi0.4%100.0%
Lead city2.06 sq mi0.3%100.0%
Mountain Plains CDP1.59 sq mi0.2%100.0%
St. Onge CDP1.34 sq mi0.2%100.0%
Crook City CDP0.91 sq mi0.1%100.0%
Whitewood city0.64 sq mi0.1%95.4%
Central City city0.15 sq mi<0.1%95.3%

Showing all 10 places

Overlapping Congressional Districts

Congressional districtPopulation in bothShare of this district's populationShare of the congressional district's populationShare of this district's land
SD At-Large25,768100.0%2.9%100.0%

Source: U.S. Census Bureau 2020 blocks and 2025 block equivalency files (119th Congress, 2024 state legislative plans).

Voters

Registered Voters
24,339
Active Voters
22,384 (92.0%)

Party Registration

PartyVotersShare
Democratic4,21017.3%
Republican13,10653.8%
Unaffiliated3,12512.8%
Other parties3,89816.0%
No party recorded00.0%

Turnout by Cycle

CycleGeneralDemocratic PrimaryRepublican Primary
2023–202415,458 (63.5%)0 (0.0%)0 (0.0%)
2021–202211,988 (49.3%)0 (0.0%)0 (0.0%)
2019–202013,088 (53.8%)0 (0.0%)0 (0.0%)
2017–20189,952 (40.9%)0 (0.0%)0 (0.0%)
2015–201610,221 (42.0%)0 (0.0%)0 (0.0%)
2013–20147,243 (29.8%)0 (0.0%)0 (0.0%)
2011–20128,724 (35.8%)0 (0.0%)0 (0.0%)

Turnout counts today's registered voters with a counted ballot in the cycle's elections (the odd and even year), as a share of today's registered voters. Voters who have since left the rolls are not counted.

Browse the voter list for this district (premium access; sign-in required)

Source: Civitech voter file snapshot as of 01/20/2026. These are registered voters, separate from the Census population figures. Counts under 10 are suppressed and shown as "<10".

Demographics

Total Population
27,233
Median Age
44.8
Median Household Income
$73,384 (± $4,448)
High School Graduate or Higher (age 25+)
95.4%
Bachelor's Degree or Higher (age 25+)
32.9%

Population by Age

GroupPeopleShare
Under 184,43516.3%
18 to 6415,98558.7%
65 and over6,81325.0%

Population by Race and Hispanic Origin

GroupPeopleShare
Hispanic or Latino (any race)1,0573.9%
White, not Hispanic24,18288.8%
Black, not Hispanic690.3%
Asian, not Hispanic1220.4%
American Indian / Alaska Native, not Hispanic6752.5%
Native Hawaiian / Pacific Islander, not Hispanic220.1%
Some other race, not Hispanic660.2%
Two or more races, not Hispanic1,0403.8%

Source: U.S. Census Bureau, American Community Survey 2020-2024 ACS 5-year estimates (tables B01001, B01002, B01003, B03002, B15003, B19013) for this state legislative district. Estimates are survey-based; ± figures are 90% margins of error.

Citizen Voting Age Population

Total Citizen Population
27,054
Citizen Voting Age Population (CVAP)
22,624

Citizen Population by Race/Ethnicity

GroupCitizensShare
Non-Hispanic26,12796.6%
Hispanic9263.4%
White24,46690.4%
Black690.3%
Asian910.3%
American Indian / Alaska Native6762.5%
Native Hawaiian / Pacific Islander210.1%
Two or More Races490.2%

Citizen Voting Age Population by Race/Ethnicity

GroupCVAPShare
Non-Hispanic21,96197.1%
Hispanic6602.9%
White20,60591.1%
Black1220.5%
Asian4361.9%
American Indian / Alaska Native7453.3%
Native Hawaiian / Pacific Islander210.1%
Two or More Races470.2%

Source: Redistricting Data Hub / U.S. Census Bureau CVAP Special Tabulation (2020-2024 ACS 5-year).