DeKalb County, Illinois
The most common soil here is Elpaso, on about 15% of the land: a silty clay loam, smooth and slightly sticky. Danabrook and Flanagan come next.
About 2% of the land drains well, and 53% stays wet for long stretches; groundwater comes within two feet of the surface under 53% of it.
USDA rates all of the land very limited for a standard septic drain field, and 59% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 3% of the land floods occasionally or more.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The soils you're most likely standing on
The biggest named soils in DeKalb County, Illinois, each drawn five feet deep from its official USDA description, in its recorded colors.
Dots mark gravel; white flecks mark lime. Shares are by acres across the survey area, and each mapped patch usually mixes several of these soils.
The biggest mapped areas
The dominant drainage class is Moderately well drained and the dominant hydrologic group is C (slow infiltration, moderate runoff). The most common soil order is Alfisols — moderately leached forest soils with a clay-enriched subsoil. 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 DeKalb County, Illinois. Search your address to find the exact soil composition, drainage, and series details at your specific location.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Elpaso silty clay loam, 0 to 2 percent slopes | 65K | Poorly drained | B/D | Very limited | Very limited |
| Flanagan silt loam, 0 to 2 percent slopes | 57K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Danabrook silt loam, 2 to 5 percent slopes | 56K | Moderately well drained | C | Somewhat limited | Very limited |
| Drummer silty clay loam, 0 to 2 percent slopes | 43K | Poorly drained | B/D | Very limited | Very limited |
| Catlin silt loam, 2 to 5 percent slopes | 36K | Moderately well drained | C | Somewhat limited | Very limited |
| Wingate silt loam, cool mesic, 2 to 5 percent slopes | 12K | Moderately well drained | C | Very limited | Very limited |
| Otter silt loam, 0 to 2 percent slopes, frequently flooded | 12K | Poorly drained | B/D | Very limited | Very limited |
| Elburn silt loam, 0 to 2 percent slopes | 9K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Mayville silt loam, 2 to 5 percent slopes | 9K | Moderately well drained | C | Very limited | Very limited |
| Parr silt loam, 5 to 10 percent slopes, eroded | 8K | Moderately well drained | C | Somewhat limited | Very limited |
| Catlin silt loam, 0 to 2 percent slopes | 8K | Moderately well drained | C | Somewhat limited | Very limited |
| Parr silt loam, 2 to 5 percent slopes, eroded | 7K | Moderately well drained | C | Somewhat limited | Very limited |
| Harpster silty clay loam, 0 to 2 percent slopes | 6K | Poorly drained | B/D | Very limited | Very limited |
| Danabrook silt loam, 5 to 10 percent slopes, eroded | 6K | Moderately well drained | C | Somewhat limited | Very limited |
| Lisbon silt loam, 0 to 2 percent slopes | 5K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Herbert silt loam, 0 to 2 percent slopes | 5K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Kaneville silt loam, 2 to 5 percent slopes | 4K | Moderately well drained | C | Somewhat limited | Very limited |
| Octagon silt loam, 4 to 6 percent slopes, eroded | 4K | Moderately well drained | C | Somewhat limited | Very limited |
| Kidami loam, 4 to 6 percent slopes, eroded | 4K | Moderately well drained | C | Somewhat limited | Very limited |
| Kaneville silt loam, 0 to 2 percent slopes | 3K | Moderately well drained | C | Somewhat limited | Very limited |
Soil Orders in This Area
The USDA classifies every soil into one of 12 soil orders. Here are the dominant orders found in this survey area.
What This Means
Building & Foundations
About 59% 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 100% 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
Drainage is generally favorable for gardening. Adding compost and mulch will improve fertility and water retention. Test your soil's pH before planting — most vegetables prefer 6.0-7.0.