Gem County Area, Idaho
The most common soil here is Gem, on about 8% of the land: a loam, a balanced mix that crumbles in your hand. Gwin and Haw come next.
About 89% of the land drains well, and 9% stays wet for long stretches.
USDA rates 94% of the land very limited for a standard septic drain field, and 76% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 1% of the land floods occasionally or more, and bedrock lies within 40 inches under 40% of it.
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 Gem County Area, Idaho, 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 Well drained and the dominant hydrologic group is D (very slow infiltration, high runoff). 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 Gem County Area, Idaho. 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 |
|---|---|---|---|---|---|
| Haw loam, 12 to 30 percent slopes | 13K | Well drained | C | Very limited | Very limited |
| Gem and Bakeoven soils, 30 to 60 percent slopes, extremely stony | 12K | Well drained | D | Very limited | Very limited |
| Payette coarse sandy loam, 30 to 60 percent slopes | 11K | Well drained | A | Very limited | Very limited |
| Gem and Bakeoven soils, 0 to 30 percent slopes, extremely stony | 9K | Well drained | D | Very limited | Very limited |
| Chilcott-Vickery complex, 0 to 12 percent slopes | 8K | Well drained | D | Very limited | Very limited |
| Power and Purdam soils, 1 to 3 percent slopes | 8K | Well drained | C | Not limited | Very limited |
| Gem very stony clay loam, 0 to 30 percent slopes | 8K | Well drained | D | Very limited | Very limited |
| Bakeoven-Rock outcrop-Lickskillet complex, 30 to 60 percent slopes | 7K | Well drained | D | Very limited | Very limited |
| Lolalita coarse sandy loam, 30 to 60 percent slopes | 7K | Well drained | A | Very limited | Very limited |
| DeMasters stony loam, 30 to 60 percent slopes | 7K | Well drained | B | Very limited | Very limited |
| Gwin very stony loam, extremely stony surface, 0 to 30 percent slopes | 6K | Well drained | D | Very limited | Very limited |
| Gwin very stony loam, extremely stony surface, 30 to 60 percent slopes | 6K | Well drained | D | Very limited | Very limited |
| Lanktree and Chilcott loams, 7 to 12 percent slopes | 6K | Well drained | C | Somewhat limited | Somewhat limited |
| Gross cobbly loam, 30 to 60 percent slopes, stony | 6K | Well drained | C | Very limited | Very limited |
| Rainey sandy loam, 30 to 60 percent slopes | 5K | Well drained | B | Very limited | Very limited |
| Bakeoven-Lickskillet-Rock outcrop complex, 0 to 30 percent slopes | 5K | Well drained | D | Very limited | Very limited |
| Gwin very stony loam, 60 to 80 percent slopes, extremely stony | 5K | Well drained | D | Very limited | Very limited |
| Mehlhorn-Gwin very stony loams, 30 to 60 percent slopes, extremely stony | 5K | Well drained | D | Very limited | Very limited |
| Van Dusen loam, 30 to 60 percent slopes | 4K | Well drained | C | Very limited | Very limited |
| Brownlee and Ola soils, 30 to 60 percent slopes | 4K | Well drained | C | 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 76% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes. A geotechnical assessment is recommended before building.
Septic Systems
About 94% 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.