Randolph County, Illinois
The dominant drainage class is Somewhat poorly drained and the dominant hydrologic group is C/D (varies with drainage). 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 Randolph County, Illinois.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Wakeland silt loam, 0 to 2 percent slopes, frequently flooded | 20K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Marine silt loam, 2 to 5 percent slopes | 20K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Homen silt loam, 2 to 5 percent slopes | 20K | Moderately well drained | C | Somewhat limited | Very limited |
| Marine silt loam, 0 to 2 percent slopes | 14K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Menfro silt loam, 2 to 5 percent slopes | 13K | Well drained | C | Somewhat limited | Somewhat limited |
| Bunkum silty clay loam, 10 to 18 percent slopes, severely eroded | 13K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Menfro silt loam, 5 to 10 percent slopes, eroded | 11K | Well drained | B | Somewhat limited | Somewhat limited |
| Bunkum silty clay loam, 5 to 10 percent slopes, severely eroded | 11K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Bunkum-Coulterville silt loams, 2 to 5 percent slopes, eroded | 8K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Coulterville-Oconee silt loams, 0 to 2 percent slopes | 8K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Water | 8K | Not rated | Not rated | ||
| Homen silt loam, 5 to 10 percent slopes, eroded | 8K | Moderately well drained | C | Somewhat limited | Very limited |
| Wilbur silt loam, 0 to 2 percent slopes, frequently flooded | 7K | Moderately well drained | B/D | Very limited | Very limited |
| Bunkum silt loam, 5 to 10 percent slopes, eroded | 7K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Menfro silty clay loam, 10 to 18 percent slopes, severely eroded | 7K | Well drained | B | Somewhat limited | Somewhat limited |
| Hickory silt loam, 18 to 35 percent slopes | 7K | Well drained | B | Very limited | Very limited |
| Menfro-Wellston silt loam, 18 to 35 percent slopes | 6K | Well drained | B | Very limited | Very limited |
| Fults silty clay, 0 to 2 percent slopes, occasionally flooded | 5K | Poorly drained | D | Very limited | Very limited |
| Coulterville-Oconee silt loams, 2 to 5 percent slopes | 5K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Ruma silt loam, 2 to 5 percent slopes | 5K | Well drained | B | Somewhat limited | Somewhat limited |
What This Means
Building & Foundations
About 64% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 78% 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.