Bennett County, South Dakota
The dominant drainage class is Well drained and the dominant hydrologic group is B (moderate infiltration). 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 Bennett County, South Dakota.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Valentine fine sand, rolling and hilly, 9 to 60 percent slopes | 110K | Excessively drained | A | Somewhat limited | Very limited |
| Oglala-Canyon loams, 9 to 25 percent slopes | 91K | Well drained | B | Very limited | Very limited |
| Keith-Rosebud silt loams, 2 to 6 percent slopes | 84K | Well drained | B | Somewhat limited | Somewhat limited |
| Canyon-Oglala loams, 18 to 40 percent slopes | 58K | Well drained | D | Very limited | Very limited |
| Canyon-Rock outcrop association, 18 to 40 percent slopes | 36K | Well drained | D | Very limited | Very limited |
| Valentine fine sand, rolling, 9 to 24 percent slopes | 26K | Excessively drained | A | Somewhat limited | Very limited |
| Richfield-Keith silt loams, 0 to 2 percent slopes | 19K | Well drained | B | Somewhat limited | Somewhat limited |
| Richfield-Keith silt loams, 2 to 6 percent slopes | 18K | Well drained | B | Somewhat limited | Very limited |
| Mosher-Minatare complex, 0 to 6 percent slopes | 17K | Somewhat poorly drained | D | Somewhat limited | Very limited |
| Dunday-Anselmo complex, 3 to 9 percent slopes | 17K | Somewhat excessively drained | A | Not limited | Very limited |
| Valentine fine sand, 9 to 25 percent slopes | 16K | Excessively drained | A | Somewhat limited | Very limited |
| Lohmiller silty clay loam, channeled, 0 to 2 percent slopes | 15K | Well drained | C | Very limited | Very limited |
| Tuthill-Anselmo fine sandy loams, 0 to 5 percent slopes | 13K | Well drained | B | Not limited | Very limited |
| Keith silt loam, 3 to 6 percent slopes | 13K | Well drained | B | Not limited | Somewhat limited |
| Mobridge silt loam, 0 to 3 percent slopes | 13K | Well drained | B | Somewhat limited | Somewhat limited |
| Valentine-Tassel complex, hilly | 12K | Excessively drained | A | Very limited | Very limited |
| Keith-Rosebud silt loams, 0 to 2 percent slopes | 12K | Well drained | B | Somewhat limited | Somewhat limited |
| Valentine fine sand, hilly, 24 to 60 percent slopes | 12K | Excessively drained | A | Very limited | Very limited |
| Valentine fine sand, 3 to 9 percent slopes | 11K | Excessively drained | A | Not limited | Very limited |
| Anselmo-Tassel fine sandy loams, 9 to 18 percent slopes | 11K | Well drained | A | Somewhat limited | Very limited |
What This Means
Building & Foundations
About 36% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 76% 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.