Sioux County, Iowa
The dominant drainage class is 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 Sioux County, Iowa.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Galva silty clay loam, 2 to 5 percent slopes, eroded | 109K | Well drained | C | Somewhat limited | Very limited |
| Galva silty clay loam, 2 to 5 percent slopes | 71K | Well drained | C | Somewhat limited | Very limited |
| Primghar silty clay loam, 0 to 2 percent slopes | 41K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Galva silty clay loam, 5 to 9 percent slopes, eroded | 34K | Well drained | C | Somewhat limited | Very limited |
| Primghar silty clay loam, 2 to 5 percent slopes | 26K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Colo silty clay loam, deep loess, 0 to 2 percent slopes, occasionally flooded | 20K | Poorly drained | C/D | Very limited | Very limited |
| Galva silty clay loam, 0 to 2 percent slopes | 19K | Well drained | C | Somewhat limited | Very limited |
| Radford silt loam, 0 to 2 percent slopes | 15K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Marcus silty clay loam, 0 to 2 percent slopes | 13K | Poorly drained | C/D | Very limited | Very limited |
| Galva silty clay loam, terrace, 0 to 2 percent slopes | 11K | Well drained | C | Somewhat limited | Very limited |
| Radford-Judson complex, 0 to 5 percent slopes | 10K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Moody silty clay loam, cool, 2 to 6 percent slopes, eroded | 9K | Well drained | C | Somewhat limited | Very limited |
| Afton silty clay loam, 0 to 2 percent slopes, occasionally flooded | 8K | Poorly drained | C/D | Very limited | Very limited |
| Judson silty clay loam, deep loess, 2 to 5 percent slopes | 7K | Well drained | C | Somewhat limited | Very limited |
| Galva silty clay loam, terrace, 2 to 5 percent slopes | 7K | Well drained | C | Somewhat limited | Very limited |
| Ely silty clay loam, shallow loess, 2 to 5 percent slopes | 6K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Moody silty clay loam, cool, 6 to 11 percent slopes, eroded | 6K | Well drained | C | Somewhat limited | Very limited |
| Ida silt loam, 5 to 9 percent slopes, severely eroded | 5K | Well drained | B | Not limited | Somewhat limited |
| Calco silty clay loam, 0 to 2 percent slopes, occasionally flooded | 4K | Poorly drained | C/D | Very limited | Very limited |
| Wadena loam, 32 to 40 inches to sand and gravel, 0 to 2 percent | 4K | Well drained | B | Not limited | Very limited |
What This Means
Building & Foundations
About 33% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 98% 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.