Greater Delta Area, Alaska

Survey Area AK657• Alaska

The dominant drainage class is Well drained and the dominant hydrologic group is B (moderate infiltration). 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 Greater Delta 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
Water-Riverwash complex	44K			Not rated	Not rated
Nenana silt loam, 0 to 3 percent slope	37K	Well drained	B	Not limited	Very limited
Gerstle-Moosehead complex, 0 to 3 percent slopes	30K	Well drained	B	Very limited	Very limited
Salchaket very fine sandy loam	19K	Well drained	B	Very limited	Very limited
Tanacross, occasionally flooded-Histels association	16K	Poorly drained	D	Very limited	Very limited
Lupine-Jarvis complex	11K	Well drained	B	Very limited	Very limited
Chatanika-Goldstream complex, 0 to 5 percent slopes	11K	Poorly drained	D	Very limited	Very limited
Jarvis-Salchaket complex	11K	Well drained	B	Very limited	Very limited
Lupine family-Beales complex, 3 to 12 percent slopes	10K	Well drained	B	Not limited	Very limited
Nenana-Donnelly complex, 0 to 3 percent slopes	9K	Well drained	B	Not limited	Very limited
Koyukuk-Audrey family complex	8K	Well drained	B	Very limited	Very limited
Lupine very fine sandy loam	8K	Well drained	B	Very limited	Very limited
Saulich-Chatanika complex, 3 to 7 percent slopes	7K	Very poorly drained	D	Very limited	Very limited
Tanana silt loam	7K	Poorly drained	D	Very limited	Very limited
Southpaw-Butchlake complex, 0 to 12 percent slopes	7K	Well drained	B	Not limited	Very limited
Interior Alaska Lowlands, Water	7K			Not rated	Not rated
Steese silt loam, 12 to 20 percent slopes	7K	Well drained	B	Very limited	Very limited
Fairbanks silt loams, gullied, 7 to 70 percent slopes	7K	Well drained	B	Somewhat limited	Somewhat limited
Gerstle-Tanana complex	7K	Well drained	B	Very limited	Very limited
Gerstle-Tanacross families complex, 0 to 4 percent slopes	6K	Moderately 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.

Inceptisols

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

Gelisols

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

Entisols

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

What This Means

Building & Foundations

About 55% of soils are rated "very limited" for dwellings with basements. Specific challenges include poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.

Septic Systems

About 78% 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

Drainage is generally favorable for gardening. Adding compost and mulch will improve fertility and water retention. Test your soil's pH before planting — most vegetables prefer 6.0-7.0.