Todd County, South Dakota
The most common soil here is Anselmo, on about 14% of the land: a fine sandy loam, gritty and crumbly. Valentine and Tuthill come next.
About 91% of the land drains well, and 5% stays wet for long stretches; groundwater comes within two feet of the surface under 3% of it.
USDA rates 92% of the land very limited for a standard septic drain field, and 26% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 4% of the land floods occasionally or more, and bedrock lies within 40 inches under 52% of it.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The soils you're most likely standing on
The biggest named soils in Todd County, South Dakota, each drawn five feet deep from its official USDA description, in its recorded colors.
Dots mark gravel; white flecks mark lime. Shares are by acres across the survey area, and each mapped patch usually mixes several of these soils.
The biggest mapped areas
The dominant drainage class is Well drained and the dominant hydrologic group is A (high infiltration, low 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 Todd 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 |
|---|---|---|---|---|---|
| Anselmo-Longpine fine sandy loams, 9 to 21 percent slopes | 82K | Well drained | A | Somewhat limited | Very limited |
| Holt-Vetal fine sandy loams, 3 to 9 percent slopes | 55K | Well drained | B | Not limited | Very limited |
| Valentine-Dunday complex, 3 to 9 percent slopes | 52K | Excessively drained | A | Not limited | Very limited |
| Valentine fine sand, rolling and hilly, 9 to 60 percent slopes | 40K | Excessively drained | A | Somewhat limited | Very limited |
| Anselmo fine sandy loam, 3 to 6 percent slopes | 35K | Well drained | A | Not limited | Very limited |
| Keota-Epping silt loams, 9 to 21 percent slopes | 35K | Well drained | C | Somewhat limited | Very limited |
| Longpine-Ronson fine sandy loams, 3 to 30 percent slopes | 30K | Well drained | D | Very limited | Very limited |
| Valentine fine sand, 9 to 25 percent slopes | 27K | Excessively drained | A | Somewhat limited | Very limited |
| Anselmo-Vetal fine sandy loams, 0 to 2 percent slopes | 20K | Well drained | A | Not limited | Very limited |
| Kadoka-Epping silt loams, 3 to 9 percent slopes | 20K | Well drained | C | Somewhat limited | Very limited |
| Anselmo fine sandy loam, 6 to 11 percent slopes | 19K | Well drained | A | Somewhat limited | Very limited |
| Tuthill-Anselmo fine sandy loams, 3 to 9 percent slopes | 18K | Well drained | B | Not limited | Somewhat limited |
| Valentine-Tassel complex, 5 to 30 percent slopes | 18K | Excessively drained | A | Very limited | Very limited |
| Loup-Elsmere loamy fine sands | 16K | Poorly drained | D | Very limited | Very limited |
| McKelvie-Peji complex, 40 to 80 percent slopes | 15K | Excessively drained | A | Very limited | Very limited |
| Keota-Rock outcrop complex, 16 to 40 percent slopes | 15K | Well drained | D | Very limited | Very limited |
| Holt fine sandy loam, 0 to 3 percent slopes | 14K | Well drained | B | Somewhat limited | Very limited |
| Tuthill silt loam, 0 to 3 percent slopes | 14K | Well drained | B | Not limited | Somewhat limited |
| Keota-Kadoka silt loams, 9 to 15 percent slopes | 14K | Well drained | C | Somewhat limited | Very limited |
| Richfield-Tuthill silt loams, 2 to 9 percent slopes | 13K | Well drained | B | Not 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.
What This Means
Building & Foundations
About 26% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 92% 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.