Upper Tanana Area, Alaska

Survey Area AK640• Alaska

The dominant drainage class is Very poorly drained and the dominant hydrologic group is D (very slow infiltration, high runoff). The most common soil order is Inceptisols — young soils with minimal horizon development but more than Entisols. 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 Upper Tanana 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
Tanana silt loam, 0 to 3 percent slopes	31K	Poorly drained	D	Very limited	Very limited
Goldstream and Histosols, 0 to 3 percent slopes	24K	Very poorly drained	D	Very limited	Very limited
Goldstream peat, 0 to 3 percent slopes	20K	Very poorly drained	D	Very limited	Very limited
Water	15K			Not rated	Not rated
Jarvis-Stratify complex, 0 to 7 percent slopes	11K	Well drained	B	Very limited	Very limited
Steese-Ester association, 12 to 45 percent slopes	10K	Well drained	B	Very limited	Very limited
Koyukuk silt loam, 3 to 7 percent slopes	10K	Well drained	B	Not limited	Very limited
Goldstream-Tanana complex, 0 to 3 percent slopes	8K	Very poorly drained	D	Very limited	Very limited
Stratify and Riverwash, 0 to 3 percent slopes	6K	Moderately well drained	C	Very limited	Very limited
Riverwash	6K			Not rated	Not rated
Salchaket-Riverwash association, 0 to 3 percent slopes	5K	Well drained	B	Very limited	Very limited
Nenana silt loam, 3 to 7 percent slopes	5K	Well drained	B	Not limited	Very limited
Nenana silt loam, 0 to 3 percent slopes	5K	Well drained	B	Not limited	Very limited
Minchumina peat, 3 to 7 percent slopes	4K	Well drained	D	Very limited	Very limited
Goldstream peat, 3 to 7 percent slopes	4K	Very poorly drained	D	Very limited	Very limited
Ester-Steese association, 7 to 12 percent slopes	3K	Very poorly drained	D	Very limited	Very limited
Tanana, moderately wet-Goldstream complex, 0 to 3 percent slopes	3K	Somewhat poorly drained	C	Very limited	Very limited
Nenana silt loam, 12 to 45 percent slopes	3K	Well drained	B	Very limited	Very limited
Goodpaster variant-Goldstream complex, 0 to 3 percent slopes	3K	Poorly drained	D	Very limited	Very limited
Goldstream peat, 7 to 12 percent slopes	2K	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.

Inceptisols

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

Entisols

Young soils with little development — found on floodplains, dunes, and steep slopes. Properties vary widely by setting.

Histosols

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

What This Means

Building & Foundations

About 77% 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 88% 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.