Tongass National Forest - Klukwah and Takshanuk Mountains Area, Alaska
The most common soil here is E22-maritime subalpine scrub-gravelly colluvial slopes, on about 7% of the land. E22-maritime subalpine wet meadow-scrub-organic slopes and E22-maritime alpine scrub-gravelly colluvial slopes, shallow come next.
About 0% of the land drains well; groundwater comes within two feet of the surface under 13% of it.
USDA rates 58% of the land very limited for a standard septic drain field, and 58% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: bedrock lies within 40 inches under 98% of it.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The biggest mapped areas
The dominant drainage class is Moderately well drained and the dominant hydrologic group is B/D (varies with drainage). The most common soil order is Histosols — organic soils (peat/muck) formed in wetlands. 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 Tongass National Forest - Klukwah and Takshanuk Mountains 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 |
|---|---|---|---|---|---|
| Southern Alaska Coastal Mountains-Maritime Subalpine and Alpine-Mountains | 75K | Very limited | Very limited | ||
| Southern Alaska Coastal Mountains-Maritime Alpine-Barren Mountains | 69K | Not rated | Not rated | ||
| Southern Alaska Coastal Mountains-Maritime Upland-Mountains | 18K | Moderately well drained | B/D | Very limited | Very limited |
| Southern Alaska Coastal Mountains-Maritime Lowland-Flood Plains and Terraces | 3K | Very poorly drained | A/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.
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. A geotechnical assessment is recommended before building.
Septic Systems
About 58% 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.