Clark County, Illinois
The dominant drainage class is 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 Clark County, Illinois.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Whitson silt loam, 0 to 2 percent slopes | 29K | Poorly drained | C/D | Very limited | Very limited |
| Cisne silt loam, 0 to 2 percent slopes | 28K | Poorly drained | C/D | Very limited | Very limited |
| Hickory-Rock outcrop complex, 35 to 60 percent slopes | 25K | Well drained | B | Very limited | Very limited |
| Shoals silt loam, 0 to 2 percent slopes, frequently flooded | 23K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Stoy silt loam, 2 to 5 percent slopes | 22K | Somewhat poorly drained | D | Very limited | Very limited |
| Newberry silt loam, 0 to 2 percent slopes | 17K | Poorly drained | C/D | Very limited | Very limited |
| Stoy silt loam, 0 to 2 percent slopes | 14K | Somewhat poorly drained | D | Very limited | Very limited |
| Cowden silt loam, 0 to 2 percent slopes | 13K | Poorly drained | C/D | Very limited | Very limited |
| Ebbert silt loam, 0 to 2 percent slopes | 12K | Very poorly drained | C/D | Very limited | Very limited |
| Bluford silt loam, 2 to 5 percent slopes, eroded | 11K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Ava silt loam, 2 to 5 percent slopes | 11K | Moderately well drained | C | Very limited | Very limited |
| Wynoose silt loam, 0 to 2 percent slopes | 8K | Poorly drained | C/D | Very limited | Very limited |
| Hickory silt loam, 18 to 35 percent slopes | 8K | Well drained | B | Very limited | Very limited |
| Stonelick loam, 0 to 2 percent slopes, frequently flooded | 6K | Well drained | B | Very limited | Very limited |
| Hickory-Atlas silt loams, 10 to 18 percent slopes, eroded | 6K | Well drained | B | Somewhat limited | Very limited |
| Carmi sandy loam, 0 to 2 percent slopes, rarely flooded | 5K | Well drained | A | Very limited | Very limited |
| Bluford silt loam, 0 to 2 percent slopes | 5K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Weir silt loam, 0 to 2 percent slopes | 4K | Poorly drained | D | Very limited | Very limited |
| Cisne-Huey silt loams, 0 to 2 percent slopes | 3K | Poorly drained | C/D | Very limited | Very limited |
| Hoyleton silt loam, 2 to 5 percent slopes | 3K | Somewhat poorly drained | C/D | Very limited | Very limited |
What This Means
Building & Foundations
About 97% 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 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.