Clay County, Iowa
The most common soil here is McCreath, on about 13% of the land: a silty clay loam, smooth and slightly sticky. Gillett Grove and Clarion come next.
About 14% of the land drains well, and 66% stays wet for long stretches; groundwater comes within two feet of the surface under 66% of it.
USDA rates 95% of the land very limited for a standard septic drain field, and 68% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 9% 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 Clay County, Iowa, 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 Somewhat poorly drained and the dominant hydrologic group is C/D (varies with drainage). The most common soil order is Mollisols — grassland soils with a thick, dark, fertile topsoil rich in organic matter. 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 Clay County, Iowa. 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 |
|---|---|---|---|---|---|
| McCreath silty clay loam, 0 to 2 percent slopes | 49K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Gillett Grove silty clay loam, 0 to 2 percent slopes | 37K | Poorly drained | C/D | Very limited | Very limited |
| Clarion loam, 2 to 6 percent slopes | 23K | Moderately well drained | C | Somewhat limited | Very limited |
| Everly clay loam, 2 to 5 percent slopes | 17K | Moderately well drained | C | Somewhat limited | Very limited |
| Wadena loam, 0 to 2 percent slopes | 17K | Well drained | B | Not limited | Very limited |
| Sac silty clay loam, loam substratum, 2 to 5 percent slopes | 14K | Moderately well drained | C | Somewhat limited | Very limited |
| Nicollet clay loam, 1 to 3 percent slopes | 14K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Webster clay loam, 0 to 2 percent slopes | 13K | Poorly drained | C/D | Very limited | Very limited |
| Ransom silty clay loam, 1 to 3 percent slopes | 12K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Canisteo clay loam, 0 to 2 percent slopes | 12K | Poorly drained | C/D | Very limited | Very limited |
| Cylinder loam, 0 to 2 percent slopes | 11K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Wilmonton clay loam, 1 to 3 percent slopes | 10K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Colo silty clay loam, deep loess, 0 to 2 percent slopes, occasionally flooded | 9K | Poorly drained | C/D | Very limited | Very limited |
| Clarion loam, 6 to 10 percent slopes, moderately eroded | 8K | Well drained | B | Somewhat limited | Somewhat limited |
| Letri clay loam, 0 to 2 percent slopes | 8K | Poorly drained | C/D | Very limited | Very limited |
| Biscay clay loam, 0 to 2 percent slopes | 8K | Poorly drained | C/D | Very limited | Very limited |
| Afton silty clay loam, Sheldon creek formation, 0 to 2 percent slopes, occasionally flooded | 6K | Poorly drained | C/D | Very limited | Very limited |
| Talcot clay loam, 32 to 40 inches to sand and gravel, 0 to 2 percent slopes | 6K | Poorly drained | C/D | Very limited | Very limited |
| Wadena loam, 2 to 6 percent slopes | 6K | Well drained | B | Not limited | Very limited |
| Wilmonton silty clay loam, 1 to 3 percent slopes | 4K | Somewhat poorly drained | C/D | Very 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 68% 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 95% of soils are rated "very limited" for septic absorption fields. Poorly drained soils can't absorb septic effluent effectively. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Many soils hold water for extended periods. Raised beds are highly recommended to improve drainage for vegetables. Well-adapted native plants and water-loving species will do best in natural conditions.