Marion County, Iowa
The dominant drainage class is Moderately well drained and the dominant hydrologic group is C (slow infiltration, moderate runoff). 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 Marion County, Iowa.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Munterville silt loam, 14 to 18 percent slopes, moderately eroded | 21K | Moderately well drained | D | Very limited | Very limited |
| Water, lakes and reservoirs | 18K | Not rated | Not rated | ||
| Clinton silt loam, 9 to 14 percent slopes, eroded | 15K | Moderately well drained | C | Somewhat limited | Very limited |
| Ladoga silt loam, 5 to 9 percent slopes, eroded | 15K | Moderately well drained | C | Somewhat limited | Very limited |
| Sharpsburg silty clay loam, 5 to 9 percent slopes, eroded | 13K | Moderately well drained | C | Somewhat limited | Very limited |
| Clinton silt loam, 5 to 9 percent slopes, eroded | 13K | Moderately well drained | C | Somewhat limited | Very limited |
| Sharpsburg silty clay loam, 2 to 5 percent slopes | 13K | Moderately well drained | C | Somewhat limited | Very limited |
| Grundy silty clay loam, 2 to 5 percent slopes | 11K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Clearfield-Arispe silty clay loams, 5 to 9 percent slopes, moderately eroded | 10K | Poorly drained | C/D | Very limited | Very limited |
| Ladoga silt loam, 9 to 14 percent slopes, eroded | 10K | Moderately well drained | C | Somewhat limited | Very limited |
| Pershing silt loam, 5 to 9 percent slopes, moderately eroded | 9K | Somewhat poorly drained | D | Very limited | Very limited |
| Lawson-Quiver-Nodaway complex, 0 to 2 percent slopes, occasionally flooded | 9K | Poorly drained | C/D | Very limited | Very limited |
| Lindley loam, 14 to 18 percent slopes | 7K | Well drained | C | Very limited | Very limited |
| Colo, occasionally flooded-Ely silty clay loams, dissected till plain, 2 to 5 percent slopes | 6K | Poorly drained | C/D | Very limited | Very limited |
| Otley silty clay loam, 5 to 9 percent slopes, eroded | 6K | Moderately well drained | C | Very limited | Very limited |
| Lamoni silty clay loam, 9 to 14 percent slopes, moderately eroded | 6K | Somewhat poorly drained | D | Very limited | Very limited |
| Munterville silt loam, 9 to 14 percent slopes, moderately eroded | 6K | Moderately well drained | D | Very limited | Very limited |
| Munterville silt loam, 18 to 25 percent slopes, moderately eroded | 6K | Moderately well drained | D | Very limited | Very limited |
| Weller silt loam, 5 to 9 percent slopes, moderately eroded | 5K | Moderately well drained | D | Very limited | Very limited |
| Ladoga silt loam, 2 to 5 percent slopes | 5K | Moderately well drained | C | Somewhat limited | Very limited |
What This Means
Building & Foundations
About 49% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 91% 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.