Johnson County, Kansas
The dominant drainage class is Moderately well drained and the dominant hydrologic group is D (very slow infiltration, high runoff). 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 Johnson County, Kansas.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Chillicothe silt loam, 2 to 5 percent slopes | 54K | Moderately well drained | D | Very limited | Very limited |
| Woodson silt loam, 1 to 3 percent slopes | 46K | Somewhat poorly drained | D | Very limited | Very limited |
| Oska-Martin silty clay loams, 4 to 8 percent slopes | 46K | Well drained | D | Very limited | Very limited |
| Sharpsburg-Urban land complex, 4 to 8 percent slopes | 22K | Moderately well drained | C | Very limited | Very limited |
| Grundy silt loam, 1 to 3 percent slopes | 16K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Sogn-Vinland complex, 3 to 25 percent slopes | 14K | Somewhat excessively drained | D | Very limited | Very limited |
| Martin silty clay loam, 3 to 7 percent slopes | 10K | Moderately well drained | C/D | Very limited | Very limited |
| Kennebec silt loam, occasionally flooded | 10K | Moderately well drained | C | Very limited | Very limited |
| Vinland-Rock outcrop complex, 15 to 45 percent slopes | 9K | Somewhat excessively drained | D | Very limited | Very limited |
| Kennebec silt loam, frequently flooded | 7K | Moderately well drained | B | Very limited | Very limited |
| Ladoga silt loam, 3 to 8 percent slopes | 6K | Moderately well drained | C | Very limited | Very limited |
| Summit silty clay loam, 3 to 7 percent slopes | 5K | Moderately well drained | C | Very limited | Very limited |
| Bucyrus silty clay loam, 1 to 3 percent slopes | 5K | Moderately well drained | C | Very limited | Very limited |
| Pawnee clay loam, 4 to 8 percent slopes, eroded | 5K | Moderately well drained | D | Very limited | Very limited |
| Sharpsburg silt loam, 4 to 8 percent slopes | 5K | Moderately well drained | C | Very limited | Very limited |
| Morrill loam, 3 to 7 percent slopes | 5K | Well drained | C | Somewhat limited | Very limited |
| Sibleyville loam, 3 to 7 percent slopes | 5K | Well drained | C | Somewhat limited | Very limited |
| Chase silt loam, occasionally flooded | 4K | Somewhat poorly drained | D | Very limited | Very limited |
| Verdigris silt loam, 0 to 1 percent slopes, frequently flooded | 3K | Well drained | B | Very limited | Very limited |
| Wagstaff-Summit complex, 3 to 8 percent slopes | 3K | Moderately well drained | D | Very limited | Very limited |
What This Means
Building & Foundations
About 96% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas, flood-prone areas. 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.