Brule and Buffalo Counties, South Dakota

Survey Area SD603• South Dakota

The dominant drainage class is Well drained and the dominant hydrologic group is C (slow infiltration, moderate runoff). The most common soil order is Mollisols — grassland soils with a thick, dark, fertile topsoil rich in organic matter. This report summarizes the major soil map units across the survey area to help you understand what to expect when buying, building, or gardening in Brule and Buffalo Counties, South Dakota. Search your address to find the exact soil composition, drainage, and series details at your specific location.

Soil Map Unit	Acres	Drainage	Hydro Group	Dwellings	Septic
Highmore-Mobridge silt loams, 0 to 4 percent slopes	99K	Well drained	B	Not limited	Somewhat limited
Highmore-Java complex, 1 to 5 percent slopes	97K	Well drained	C	Somewhat limited	Very limited
Eakin-DeGrey silt loams, 0 to 2 percent slopes	76K	Well drained	C	Not limited	Very limited
Sansarc-Opal clays, 9 to 25 percent slopes	52K	Well drained	D	Very limited	Very limited
Glenham-Java-Prosper loams, 1 to 6 percent slopes	46K	Well drained	C	Not limited	Very limited
Mobridge-Plankinton silt loams	36K	Moderately well drained	B	Somewhat limited	Somewhat limited
Promise clay, 3 to 6 percent slopes	30K	Well drained	D	Very limited	Very limited
Plankinton silt loam	30K	Poorly drained	D	Very limited	Very limited
Water	26K			Not rated	Not rated
Promise clay, 0 to 3 percent slopes	25K	Well drained	D	Very limited	Very limited
Highmore-Java complex, 5 to 9 percent slopes	25K	Well drained	C	Somewhat limited	Very limited
Opal-Promise clays, 6 to 9 percent slopes	24K	Well drained	D	Very limited	Very limited
Mobridge silt loam, 0 to 2 percent slopes	21K	Moderately well drained	C	Somewhat limited	Very limited
Chantier-Sansarc clays, 3 to 15 percent slopes	17K	Well drained	D	Very limited	Very limited
Uly silt loam, 2 to 6 percent slopes	17K	Well drained	B	Not limited	Somewhat limited
Java-Betts loams, 9 to 20 percent slopes	13K	Well drained	B	Very limited	Very limited
Opal clay, 3 to 6 percent slopes	11K	Well drained	D	Very limited	Very limited
Java-Glenham loams, 6 to 9 percent slopes	11K	Well drained	B	Somewhat limited	Very limited
Beadle-Jerauld complex, 0 to 6 percent slopes	11K	Well drained	C	Somewhat limited	Very limited
Betts-Java loams, 20 to 40 percent slopes	10K	Well drained	C	Very limited	Very limited

Soil Orders in This Area

The USDA classifies every soil into one of 12 soil orders. Here are the dominant orders found in this survey area.

Mollisols

Fertile grassland soils with thick, dark topsoil. Among the best for agriculture, building, and gardening.

Vertisols

High-clay soils that shrink and swell dramatically. Fertile but challenging for foundations and septic systems.

Entisols

Young soils with little development — found on floodplains, dunes, and steep slopes. Properties vary widely by setting.

What This Means

Building & Foundations

About 31% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.

Septic Systems

About 73% of soils are rated "very limited" for septic absorption fields. Despite good drainage overall, limitations may stem from shallow bedrock, steep slopes, or seasonal conditions. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.

Gardening & Agriculture

Well-drained soils on sloped terrain — good for most plants but watch for erosion. Terracing, contour planting, and mulching help retain moisture and topsoil. Drip irrigation is more effective than sprinklers on slopes.