Brooks Range and Davidson Mountains Area, Alaska
The most common soil here is E34-Boreal alpine dwarf scrub-gravelly colluvial slopes, on about 14% of the land. E34-Boreal alpine scrub-gravelly colluvial slopes and E34-Boreal forest-gravelly till slopes come next.
About 72% of the land drains well, and 27% stays wet for long stretches; groundwater comes within two feet of the surface under 66% of it.
USDA rates all of the land very limited for a standard septic drain field, and 96% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: bedrock lies within 40 inches under 31% 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 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 Spodosols — acidic forest soils with a distinctive leached layer, common under conifers. 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 Brooks Range and Davidson Mountains Area, Alaska. 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 |
|---|---|---|---|---|---|
| Interior Brooks Range Mountains-Boreal Alpine-Rugged Mountains | 1.1M | Well drained | B | Very limited | Very limited |
| Interior Brooks Range Mountains-Boreal Upland and Lowland-Glaciated Valleys | 851K | Well drained | B | Very limited | Very limited |
| Interior Alaska Highlands-Boreal Upland-Hills and Plains | 400K | Poorly drained | D | Very limited | Very limited |
| Interior Alaska Highlands-Boreal Upland and Alpine-Plains and Hills | 362K | Poorly drained | D | Very limited | Very limited |
| Interior Brooks Range Mountains-Boreal Alpine and Subalpine-Rounded Mountains | 297K | Well drained | B | Very limited | Very limited |
| Yukon Flats-Boreal Upland-Plains and Hills | 250K | Poorly drained | D | Very limited | Very limited |
| Interior Brooks Range Mountains-Boreal Upland-Rounded Mountains | 163K | Well drained | B | Very limited | Very limited |
| Interior Alaska Highlands-Boreal Upland and Subalpine-Rounded Mountains | 160K | Well drained | B | Not limited | Very limited |
| Interior Brooks Range Mountains-Boreal Upland and Alpine-Glaciated Valleys | 61K | Well drained | B | Very limited | Very limited |
| Interior Alaska Highlands-Boreal Alpine and Upland-Rugged Mountains | 48K | Well drained | B | Very limited | Very limited |
| Interior Brooks Range Mountains-Boreal Alpine-Barren Mountains | 45K | Very limited | Very limited | ||
| Interior Alaska Highlands-Boreal Upland-Rounded Mountains, Acid | 44K | Well drained | A | Very limited | Very limited |
| Interior Alaska Highlands-Boreal Lowland-Flood Plains and Terraces | 25K | Poorly drained | D | Very limited | Very limited |
| Interior Alaska Highlands-Boreal Alpine and Upland-Rounded Mountains, Acid | 18K | Well drained | B | Very limited | Very limited |
| Interior Brooks Range Mountains-Boreal Alpine and Subalpine-Rugged Mountains, Calcareous | 8K | Well drained | D | Very limited | Very limited |
| Interior Alaska Highlands-Boreal Upland and Alpine-Rugged Mountains | 6K | Well drained | A | Very limited | Very limited |
| Interior Brooks Range Mountains-Boreal Water,Fresh | 5K | Not limited | Not limited | ||
| Yukon Flats-Boreal Lowland-Alluvial Plains | 4K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Northern Brooks Range Mountains-Arctic Upland-Barren Mountains | 2K | Very limited | Very limited | ||
| Northern Brooks Range Mountains-Arctic Upland-Rugged Mountains | 744 | Well drained | B | 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 96% 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 100% 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.