Johnson County, Missouri
The dominant drainage class is Somewhat poorly drained and the dominant hydrologic group is C (slow infiltration, moderate 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, Missouri.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Sampsel silty clay loam, 5 to 9 percent slopes, severely eroded | 79K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Deepwater silt loam, 5 to 9 percent slopes, eroded | 35K | Moderately well drained | C | Somewhat limited | Very limited |
| Mandeville silt loam, 5 to 9 percent slopes | 32K | Well drained | C | Somewhat limited | Very limited |
| Haig silt loam, 0 to 2 percent slopes | 29K | Poorly drained | D | Very limited | Very limited |
| Sampsel silty clay loam, 2 to 5 percent slopes | 27K | Poorly drained | C/D | Very limited | Very limited |
| Arisburg silt loam, 1 to 5 percent slopes | 24K | Somewhat poorly drained | C | Very limited | Very limited |
| Snead silty clay loam, warm, 5 to 14 percent slopes, eroded | 23K | Moderately well drained | D | Very limited | Very limited |
| Deepwater silt loam, 2 to 5 percent slopes | 23K | Moderately well drained | C | Somewhat limited | Very limited |
| Polo silt loam, 2 to 5 percent slopes | 18K | Well drained | C | Very limited | Very limited |
| Norris channery silt loam, 5 to 14 percent slopes | 16K | Well drained | D | Very limited | Very limited |
| Nodaway silt loam, heavy till, 0 to 2 percent slopes, occasionally flooded | 16K | Moderately well drained | B | Very limited | Very limited |
| Gorin silt loam, 5 to 9 percent slopes, eroded | 14K | Somewhat poorly drained | C | Very limited | Very limited |
| Zook silty clay loam, 0 to 2 percent slopes, frequently flooded | 14K | Poorly drained | C/D | Very limited | Very limited |
| Hartwell silt loam, 1 to 3 percent slopes, eroded | 13K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Hartwell silt loam, 0 to 1 percent slopes | 12K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Nodaway silt loam, 1 to 3 percent slopes, occasionally flooded | 11K | Moderately well drained | B | Very limited | Very limited |
| Dockery silty clay loam, 0 to 2 percent slopes, frequently flooded | 11K | Somewhat poorly drained | C | Very limited | Very limited |
| Snead-Rock outcrop complex, warm, 5 to 14 percent slopes | 11K | Moderately well drained | D | Very limited | Very limited |
| Weller silt loam, 2 to 5 percent slopes | 10K | Moderately well drained | D | Very limited | Very limited |
| Snead-Rock outcrop complex, warm, 14 to 30 percent slopes | 9K | Moderately well drained | D | Very limited | Very limited |
What This Means
Building & Foundations
About 78% 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. Poorly drained soils can't absorb septic effluent effectively. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Many soils hold water for extended periods. Raised beds are highly recommended to improve drainage for vegetables. Well-adapted native plants and water-loving species will do best in natural conditions.