Bristol Bay-Northern Alaska Peninsula, North and Bordering Areas, Alaska

Survey Area AK636• Alaska

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 Bristol Bay-Northern Alaska Peninsula, North and Bordering Areas, 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
Western Maritime Eolian Plains with Common Permafrost, Very Wet	583K	Very poorly drained	B/D	Very limited	Very limited
Yukon-Kuskokwim Highlands-Subalpine and Boreal Low Mountains	447K	Well drained	B/D	Very limited	Very limited
Yukon-Kuskokwim Highlands-Alpine and Subalpine Low Mountains	419K	Well drained	B	Very limited	Very limited
Western Maritime Mountains	392K	Well drained	C	Somewhat limited	Very limited
Ahklun Mountains-High Elevation and Western Maritime Mountains	365K	Well drained	B	Very limited	Very limited
Okstukuk-Typic Haplocryods complex, 0 to 8 percent slopes	353K	Well drained	B	Somewhat limited	Somewhat limited
Okstukuk-Mosquitopoint-Typic Haplocryods association, 0 to 3 percent slopes	331K	Well drained	B	Somewhat limited	Somewhat limited
Western Maritime Eolian Hills and Plains	292K	Very poorly drained	C	Very limited	Very limited
Western Maritime Glaciated Plains and Flood Plains, Wet	259K	Well drained	C	Not limited	Very limited
Yukon-Kuskokwim Highlands-Alpine Mountains	248K	Well drained	B	Very limited	Very limited
Western Maritime Glaciated Hills and Plains	248K	Well drained	C	Not limited	Very limited
Western Maritime Eolian Plains and Flood Plains with Common Permafrost, Wet	221K	Moderately well drained	C/D	Very limited	Very limited
Interior Alaska Mountains-Boreal Low Mountains and Plains	207K	Well drained	C	Somewhat limited	Somewhat limited
Yukon-Kuskokwim Highlands-Alpine and Subalpine Mountains	194K	Well drained	B	Somewhat limited	Somewhat limited
Western Maritime Organic and Glaciated Plains	194K	Well drained	B/D	Very limited	Very limited
Western Maritime Eolian Plains, Very Wet	190K	Very poorly drained	B/D	Very limited	Very limited
Interior Alaska Mountains-Boreal Plains, Wet	174K	Well drained	C	Very limited	Very limited
Okstukuk silt loam, 0 to 5 percent slopes	172K	Well drained	B	Somewhat limited	Somewhat limited
Open Water	147K			Very limited	Very limited
Western Maritime Glaciated Plains	145K	Well drained	B	Somewhat 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.

Spodosols

Acidic forest soils with a leached layer. Common under conifers. Often have drainage issues from a compacted subsoil layer.

Inceptisols

Young but developing soils found in mountains and river terraces. Variable properties — check drainage and bedrock depth.

Histosols

Organic peat and muck soils formed in wetlands. Very poor for building (compressible) and septic. Often in regulated wetlands.

Andisols

Volcanic ash soils — light, porous, and fertile. Excellent drainage, but low density can complicate foundations.

What This Means

Building & Foundations

About 58% 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 77% 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.