Mercer County, Illinois
The dominant drainage class is Well drained and the dominant hydrologic group is B (moderate infiltration). 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 Mercer County, Illinois.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Muscatune silt loam, 0 to 2 percent slopes | 42K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Osco silt loam, 2 to 5 percent slopes | 23K | Well drained | B | Somewhat limited | Somewhat limited |
| Hickory silt loam, cool mesic, 18 to 35 percent slopes | 15K | Well drained | B | Very limited | Very limited |
| Orion silt loam, 0 to 2 percent slopes, frequently flooded | 14K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Rozetta silt loam, 2 to 5 percent slopes | 13K | Well drained | B | Somewhat limited | Somewhat limited |
| Fayette silt loam, glaciated, 5 to 10 percent slopes, eroded | 13K | Well drained | B | Somewhat limited | Somewhat limited |
| Hickory-Sylvan silt loams, 35 to 60 percent slopes | 10K | Well drained | B | Very limited | Very limited |
| Greenbush silt loam, 5 to 10 percent slopes, eroded | 10K | Well drained | B | Somewhat limited | Somewhat limited |
| Greenbush silt loam, 2 to 5 percent slopes | 10K | Well drained | B | Somewhat limited | Somewhat limited |
| Sylvan silty clay loam, 10 to 18 percent slopes, severely eroded | 10K | Well drained | B | Somewhat limited | Somewhat limited |
| Ipava silt loam, 0 to 2 percent slopes | 9K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Titus silty clay loam, 0 to 2 percent slopes, rarely flooded | 8K | Poorly drained | C/D | Very limited | Very limited |
| Elco-Atlas silty clay loams, 10 to 18 percent slopes, severely eroded | 7K | Moderately well drained | C | Somewhat limited | Very limited |
| Seaton silt loam, 2 to 5 percent slopes | 6K | Well drained | B | Not limited | Somewhat limited |
| Osco silt loam, 5 to 10 percent slopes, eroded | 6K | Well drained | B | Somewhat limited | Somewhat limited |
| Joy silt loam, 0 to 2 percent slopes | 6K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Water | 6K | Not rated | Not rated | ||
| Atterberry silt loam, 0 to 2 percent slopes | 6K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Radford silt loam, 0 to 2 percent slopes, frequently flooded | 6K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Sparta loamy sand, Illinois till plain, 2 to 6 percent slopes | 6K | Excessively drained | A | Not limited | Very limited |
What This Means
Building & Foundations
About 51% 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 56% 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.