Sangamon 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 Sangamon County, Illinois.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Ipava silt loam, 0 to 2 percent slopes | 154K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Osco silt loam, 2 to 5 percent slopes | 63K | Well drained | B | Somewhat limited | Somewhat limited |
| Sable silty clay loam, 0 to 2 percent slopes | 62K | Poorly drained | B/D | Very limited | Very limited |
| Virden silty clay loam, 0 to 2 percent slopes | 35K | Poorly drained | C/D | Very limited | Very limited |
| Rozetta silt loam, 2 to 5 percent slopes | 28K | Well drained | B | Somewhat limited | Somewhat limited |
| Hartsburg silty clay loam, 0 to 2 percent slopes | 21K | Poorly drained | B/D | Very limited | Very limited |
| Radford silt loam, 0 to 2 percent slopes, frequently flooded | 13K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Osco silt loam, 5 to 10 percent slopes, eroded | 13K | Well drained | B | Somewhat limited | Somewhat limited |
| Sawmill silty clay loam, 0 to 2 percent slopes, frequently flooded | 13K | Poorly drained | B/D | Very limited | Very limited |
| Fayette silt loam, glaciated, 5 to 10 percent slopes, eroded | 12K | Well drained | B | Somewhat limited | Somewhat limited |
| Tice silty clay loam, 0 to 2 percent slopes, frequently flooded | 10K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Keomah silt loam, 0 to 2 percent slopes | 9K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Lawson silt loam, cool mesic, 0 to 2 percent slopes, frequently flooded | 9K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Water | 8K | Not rated | Not rated | ||
| Buckhart silt loam, 0 to 2 percent slopes | 7K | Moderately well drained | C | Somewhat limited | Very limited |
| Elkhart silt loam, 5 to 10 percent slopes, eroded | 7K | Well drained | B | Somewhat limited | Somewhat limited |
| Assumption silt loam, 5 to 10 percent slopes, eroded | 6K | Moderately well drained | C | Somewhat limited | Very limited |
| Assumption silt loam, 10 to 18 percent slopes, eroded | 6K | Moderately well drained | C | Somewhat limited | Very limited |
| Harrison silt loam, 5 to 10 percent slopes, eroded | 6K | Moderately well drained | C | Somewhat limited | Very limited |
| Herrick silt loam, 0 to 2 percent slopes | 6K | Somewhat poorly drained | C/D | Very limited | Very limited |
What This Means
Building & Foundations
About 68% of soils are rated "very limited" for dwellings with basements. Specific challenges include poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 73% 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.