Clark County Area, Idaho, Parts of Clark and Butte Counties
The most common soil here is Simeroi, on about 5% of the land: a gravelly loam, a balanced mix that crumbles in your hand. Latigo and Chickenridge come next.
About 96% of the land drains well, and 4% stays wet for long stretches; groundwater comes within two feet of the surface under 6% of it.
USDA rates 93% of the land very limited for a standard septic drain field, and 55% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 4% of the land floods occasionally or more, and bedrock lies within 40 inches under 41% 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 Clark County Area, Idaho, Parts of Clark and Butte Counties, 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 B (moderate infiltration). 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 Clark County Area, Idaho, Parts of Clark and Butte Counties. 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 |
|---|---|---|---|---|---|
| Vadnais-Chickenridge-Rock outcrop complex, 1 to 12 percent slopes | 45K | Well drained | B | Very limited | Very limited |
| Jacoby-Vickton-Eaglecone complex, 1 to 8 percent slopes | 31K | Well drained | A | Somewhat limited | Very limited |
| Malm-Matheson-Rock outcrop complex, 1 to 12 percent slopes | 25K | Well drained | B | Very limited | Very limited |
| Coffee-Rock outcrop complex, 1 to 12 percent slopes | 16K | Well drained | C | Somewhat limited | Very limited |
| Whiteknob-Medicine complex, 0 to 2 percent slopes | 16K | Somewhat excessively drained | A | Not limited | Very limited |
| Grassyridge-Malm complex, 1 to 15 percent slopes | 15K | Somewhat excessively drained | A | Not limited | Very limited |
| Chickenridge-Stoneman complex, 1 to 12 percent slopes | 14K | Well drained | B | Somewhat limited | Very limited |
| Maremma-Pyrenees, stony-Akbash complex, 0 to 12 percent slopes | 14K | Well drained | B | Very limited | Very limited |
| Idmonton-Kilgore-Alex complex, 0 to 4 percent slopes | 14K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Eaglecone-Jacoby-Blacknoll complex, 1 to 6 percent slopes | 13K | Well drained | A | Very limited | Very limited |
| Jacoby-Kuvasz-St. Anthony complex, 1 to 8 percent slopes | 13K | Well drained | A | Not limited | Very limited |
| Chickenridge-Stoneman-Vadnais complex, 1 to 12 percent slopes | 13K | Well drained | B | Somewhat limited | Very limited |
| Simeroi gravelly silt loam, 1 to 5 percent slopes | 12K | Well drained | B | Not limited | Somewhat limited |
| Blacknoll-Jipper complex, 0 to 8 percent slopes | 11K | Well drained | B | Very limited | Very limited |
| Medicine silt loam, 0 to 2 percent slopes | 11K | Well drained | B | Not limited | Somewhat limited |
| Fallert gravelly loam, 0 to 2 percent slopes | 11K | Well drained | D | Not limited | Not limited |
| Malm-Bondfarm-Matheson complex, 1 to 12 percent slopes | 11K | Well drained | B | Very limited | Very limited |
| St. Anthony gravelly loam, 1 to 5 percent slopes | 11K | Well drained | C | Not limited | Very limited |
| Zeebar-Windicreek-Poso complex, 20 to 70 percent slopes | 11K | Well drained | A | Very limited | Very limited |
| Becreek-Grassyridge complex, 0 to 2 percent slopes | 11K | Well drained | A | Not 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 55% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 93% 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.