Tanana - Kuskokwim Lowlands - Snohomish and Trimokish Hills Area, Alaska

Survey Area AK723• Alaska

The dominant drainage class is Poorly drained and the dominant hydrologic group is D (very slow infiltration, high runoff). The most common soil order is Gelisols — permafrost soils found in very cold climates. 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 Tanana - Kuskokwim Lowlands - Snohomish and Trimokish Hills 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 Alaska Lowlands-Boreal Upland-Loess Plains and Hills	1.1M	Poorly drained	D	Very limited	Very limited
Yukon-Kuskokwim Highlands-Boreal Upland-Loess Hills	552K	Poorly drained	D	Very limited	Very limited
Interior Alaska Lowlands-Boreal Lowland-Fan Terraces and Stream Terraces	518K	Poorly drained	D	Very limited	Very limited
Yukon-Kuskokwim Highlands-Boreal Upland-Rounded Mountains	407K	Well drained	B	Very limited	Very limited
Interior Alaska Lowlands-Boreal Lowland-High Flood Plains and Terraces	406K	Poorly drained	B/D	Very limited	Very limited
Interior Alaska Mountains-Boreal Glaciated Plains and Hills	394K	Poorly drained	D	Very limited	Very limited
Interior Alaska Mountains-Boreal Alpine-Barren Mountains	357K			Very limited	Very limited
Interior Alaska Mountains-Boreal Alpine-Rugged Mountains	270K	Well drained	B	Very limited	Very limited
Interior Alaska Lowlands-Boreal Lowland-Alluvial Plains, Wet	247K	Very poorly drained	D	Very limited	Very limited
Yukon-Kuskokwim Highlands-Boreal Upland-Plains and Hills	240K	Poorly drained	D	Very limited	Very limited
Yukon-Kuskokwim Highlands-Boreal Upland and Alpine-Rounded Mountains	197K	Well drained	B	Very limited	Very limited
Interior Alaska Lowlands-Boreal Lowland-Stream Terraces and Peat Plateaus	191K	Poorly drained	D	Very limited	Very limited
Interior Alaska Mountains-Boreal Alpine-Mountain Valleys	166K	Well drained	B	Very limited	Very limited
Interior Alaska Mountains-Boreal Upland and Lowland-Mountain Valleys	154K	Well drained	B	Very limited	Very limited
Interior Alaska Mountains-Boreal Alpine-Rounded Mountains	143K	Well drained	B	Very limited	Very limited
Yukon-Kuskokwim Highlands-Boreal Upland-Valleys	78K	Poorly drained	D	Very limited	Very limited
Yukon-Kuskokwim Highlands-Boreal Alpine and Subalpine-Rounded Mountains	74K	Well drained	B	Very limited	Very limited
Interior Alaska Mountains-Boreal Subalpine and Alpine-Rounded Mountains, Ash Influenced	71K	Well drained	C	Very limited	Very limited
Interior Alaska Mountains-Boreal Subalpine and Alpine-Rugged Mountains	65K	Well drained	B	Very limited	Very limited
Interior Alaska Mountains-Boreal Lowland-Flood Plains, Terraces, and Fans	58K			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.

Gelisols

Permafrost soils. Extremely challenging for construction and septic. Found almost exclusively in Alaska.

Inceptisols

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

Spodosols

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

What This Means

Building & Foundations

About 100% 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. 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.