Haakon County, South Dakota

Survey Area SD055• South Dakota

The dominant drainage class is Well drained and the dominant hydrologic group is D (very slow infiltration, high 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 Haakon County, 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
Ottumwa silty clay, 3 to 6 percent slopes	112K	Well drained	C	Very limited	Very limited
Lakoma silty clay, 6 to 15 percent slopes	95K	Well drained	D	Very limited	Very limited
Okaton-Lakoma silty clays, 15 to 40 percent slopes	64K	Well drained	D	Very limited	Very limited
Samsil clay, 15 to 45 percent slopes	54K	Well drained	D	Very limited	Very limited
Ottumwa-Lakoma complex, 3 to 6 percent slopes	53K	Well drained	D	Very limited	Very limited
Ottumwa-Lakoma silty clays, 6 to 9 percent slopes	43K	Well drained	D	Very limited	Very limited
Ree loam, 0 to 3 percent slopes	43K	Well drained	C	Somewhat limited	Very limited
Pierre-Samsil clays, 15 to 25 percent slopes	37K	Well drained	D	Very limited	Very limited
Lakoma silty clay, 6 to 9 percent slopes	33K	Well drained	D	Very limited	Very limited
Razor-Midway complex, 6 to 15 percent slopes	32K	Well drained	D	Very limited	Very limited
Pierre clay, 6 to 15 percent slopes	30K	Well drained	D	Very limited	Very limited
Schamber-Samsil complex, 6 to 60 percent slopes	29K	Well drained	A	Very limited	Very limited
Ottumwa silty clay, 0 to 3 percent slopes	27K	Well drained	C	Very limited	Very limited
Lakoma-Vivian complex, 9 to 25 percent slopes	27K	Well drained	D	Very limited	Very limited
Ottumwa-Capa complex, 0 to 3 percent slopes	25K	Well drained	C	Very limited	Very limited
Opal-Promise clays, 6 to 9 percent slopes	22K	Well drained	D	Very limited	Very limited
Opal-Sansarc clays, 6 to 15 percent slopes	20K	Well drained	D	Very limited	Very limited
Samsil-Rock outcrop complex, 9 to 60 percent slopes	20K	Well drained	D	Very limited	Very limited
Kirley-Ottumwa complex, 3 to 6 percent slopes	19K	Well drained	D	Very limited	Very limited
Ottumwa-Razor silty clays, 6 to 9 percent slopes	18K	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.

Aridisols

Dry-climate soils with low organic matter. Often have caliche layers that make excavation difficult. Low shrink-swell is good for foundations.

Entisols

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

Inceptisols

Young but developing soils found in mountains and river terraces. Variable properties — check drainage and bedrock depth.

What This Means

Building & Foundations

About 94% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes. A geotechnical assessment is recommended before building.

Septic Systems

About 100% 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.