HomeSouth DakotaPerkins County

Perkins County, South Dakota

Shrink-swell clay limits houses without basements on 18% of Perkins County's mapped land, a higher share than 68% of US counties. A shallow water table limits basements on 2%.

82% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list no flood losses here since 2016. 75% of homes were built before 1980, against 50% nationally; the median home dates from 1966.

Data as of October 13, 2026 · sources

18%

expansive clay: shrink-swell limits slab homes

2%

high water table: limits basements

82%

in drought, October 13, 2026

75%

of homes built before 1980

Soil under Perkins County

Expansive clay (limits slab homes)18.1%
High water table (limits basements)1.6%
Septic fields very limited87.8%
Clay swell (LEP, by area)3.8%
High-swell land (LEP 6%+)21.0%
Mapped soil1,849,844 acres
Soil seriesShare hereSeries nationally: expansive clay
Vebar8%n/a
Morton7%n/a
Reeder7%n/a
Cabba6%n/a
Lantry6%n/a
Bullock6%n/a
Adams County: 33%Harding County: 13%Ziebach County: 59%Meade County: 49%Corson County: 34%Butte County: 72%Hettinger County: 43%Bowman County: 32%Perkins County AdamsHardingZiebachMeadeCorsonButteHettingerBowmanPerkins
Perkins County (heavy outline) and nearby counties, shaded by expansive clay share.under 10%10-25%25-40%40-60%60%+

How we count · survey areas SD105 (2025-09-10)

What the numbers mean here

Clay swell averages a linear extensibility of 3.8% by land area here, and 21% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 18% of the mapped land.

Clay shrinks as it dries: 82% of the county is in drought on the latest map, and 18% of Perkins County's mapped land has shrink-swell clay.

Rain over the 12 months to August 2026: 17.23 in, 0.05 in above the 1991-2020 average year of 17.18 in.

USDA rates 88% of the land very limited for septic absorption fields.

Drought

82% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 13 of the last 52 weeks; the most was 100% of its area, in 7 weeks, most recently on the September 15, 2026 map.

October 21, 2025Share of area in drought, weeklyOctober 13, 2026
Category, October 13, 2026Share of county
D0 abnormally dry or worse100%
D1 moderate drought or worse82%
D2 severe or worse0%
D3 extreme or worse0%
D4 exceptional0%

Flood losses since 2016

FEMA's flood data list no flood losses in Perkins County since 2016.

Rain

Average year, 1991-202017.18 in
12 months to August 202617.23 in (+0.05)
202524.81 in (+7.63)
Wettest year since 18952019: 25.63 in
Driest year since 18951936: 5.30 in
Days with 1 inch or more, normal at BISON (3 mi away)3.2

Homes

Housing units1,744
Median year built1966
Built before 198075%
Built 2000 or later12%
Owner-occupied78%
Median value, owner-occupied$114,600
Single-family detached72%

What repairs cost

Published ranges from cost guides, not quotes. More sources, and where they disagree.

WorkRangeSource
Foundation repair, US $2,200 to $8,200 Fixr, January 27, 2026
Pier-and-beam repair, US $2,000 to $15,000 Fixr, January 27, 2026
Foundation inspection, US $300 to $600 Fixr, January 31, 2025

Nearby counties

PlaceDistanceExpansive clayHigh water table
Adams County, ND 43 mi 33% 7%
Harding County, SD 49 mi 13% 2%
Ziebach County, SD 52 mi 59% 2%
Meade County, SD 62 mi 49% 1%
Corson County, SD 64 mi 34% 3%
Butte County, SD 65 mi 72% 6%
Hettinger County, ND 66 mi 43% 7%
Bowman County, ND 66 mi 32% 4%

Sources: USDA SSURGO (September 10, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status