Monona County, Iowa
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 Monona County, Iowa.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Luton silty clay, 0 to 2 percent slopes, rarely flooded | 57K | Poorly drained | D | Very limited | Very limited |
| Napier silt loam, 5 to 9 percent slopes | 35K | Well drained | B | Not limited | Somewhat limited |
| Ida silt loam, 14 to 20 percent slopes, severely eroded | 22K | Well drained | B | Very limited | Very limited |
| Napier silt loam, 9 to 14 percent slopes | 17K | Well drained | B | Somewhat limited | Somewhat limited |
| Ida silt loam, 20 to 30 percent slopes | 15K | Well drained | B | Very limited | Very limited |
| Albaton silty clay, 0 to 2 percent slopes, rarely flooded | 14K | Poorly drained | D | Very limited | Very limited |
| Monona silt loam, 5 to 9 percent slopes, eroded | 14K | Well drained | B | Not limited | Somewhat limited |
| Ida silt loam, 20 to 30 percent slopes, severely eroded | 11K | Well drained | B | Very limited | Very limited |
| Monona silt loam, 9 to 14 percent slopes, eroded | 10K | Well drained | B | Somewhat limited | Somewhat limited |
| Ida silt loam, 9 to 14 percent slopes, severely eroded | 10K | Well drained | B | Somewhat limited | Somewhat limited |
| Onawa silty clay, 0 to 2 percent slopes, rarely flooded | 10K | Poorly drained | D | Very limited | Very limited |
| Castana silt loam, 14 to 20 percent slopes | 10K | Well drained | B | Very limited | Very limited |
| Napier silt loam, 2 to 5 percent slopes | 9K | Well drained | B | Not limited | Somewhat limited |
| Salix silty clay loam, 0 to 2 percent slopes, rarely flooded | 9K | Moderately well drained | C | Very limited | Very limited |
| Ida silt loam, 30 to 40 percent slopes | 9K | Well drained | B | Very limited | Very limited |
| Forney silty clay, 0 to 2 percent slopes, rarely flooded | 8K | Poorly drained | D | Very limited | Very limited |
| Woodbury silty clay, 0 to 2 percent slopes, rarely flooded | 7K | Poorly drained | D | Very limited | Very limited |
| Blencoe silt clay, 0 to 2 percent slopes, rarely flooded | 7K | Somewhat poorly drained | D | Very limited | Very limited |
| Rawles silt loam, 0 to 2 percent slopes, occasionally flooded | 6K | Moderately well drained | C | Very limited | Very limited |
| Kennebec silt loam, 0 to 2 percent slopes, occasionally flooded | 6K | Moderately well drained | B | Very limited | Very limited |
What This Means
Building & Foundations
About 66% 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 66% 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.