Yukon-Charley Rivers National Preserve, Alaska

Survey Area AK684• 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 Yukon-Charley Rivers National Preserve, 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
Alpine Rounded Mountains with Common Permafrost	385K	Somewhat poorly drained	D	Very limited	Very limited
Boreal Hills with Common Permafrost, Nonacid	288K	Poorly drained	D	Very limited	Very limited
Subalpine and Boreal Hills	265K	Poorly drained	D	Very limited	Very limited
Boreal and Subalpine Hills with Extensive Permafrost	210K	Poorly drained	D	Very limited	Very limited
Boreal Hills with Extensive Permafrost	204K	Poorly drained	D	Very limited	Very limited
Boreal Sedimentary Hills	181K	Poorly drained	A	Very limited	Very limited
Boreal and Subalpine Hills with Common Permafrost	104K	Somewhat excessively drained	A	Very limited	Very limited
Alpine Granitic Mountains	88K	Somewhat excessively drained	A	Very limited	Very limited
Subalpine Glaciated Hills	70K	Poorly drained	D	Very limited	Very limited
Boreal Terraces with Extensive Permafrost	59K	Very poorly drained	D	Very limited	Very limited
Boreal Eolian Hills with Common Permafrost, Wet	53K	Very poorly drained	D	Very limited	Very limited
Subalpine Hills	48K	Very poorly drained	C/D	Very limited	Very limited
Boreal Eolian Plains with Extensive Permafrost, Moist	47K	Poorly drained	D	Very limited	Very limited
Boreal Low Flood Plains	39K		D	Very limited	Very limited
Boreal Hills with Common Permafrost, Thin Surface	37K	Very poorly drained	D	Very limited	Very limited
Boreal Eolian Hills with Extensive Permafrost	36K	Very poorly drained	D	Very limited	Very limited
Alpine Granitic Mountains, Dry	34K	Somewhat excessively drained	D	Very limited	Very limited
Boreal Valley Bottoms	32K	Very poorly drained	D	Very limited	Very limited
Boreal Flood Plains with Common Permafrost	29K	Moderately well drained	B	Very limited	Very limited
Boreal Eolian Terraces with Extensive Permafrost	26K	Very poorly drained	D	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.

Mollisols

Fertile grassland soils with thick, dark topsoil. Among the best for agriculture, building, and gardening.

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.