Talkeetna and Chugach Mountains - Cook Inlet Area, Alaska
The most common soil here is E23-boreal subalpine scrub/meadow mosaic-silty acid slopes, on about 11% of the land. E23-boreal subalpine scrub/meadow mosaic-silty till slopes and E23-boreal alpine scrub-silty acid hummocks come next.
About 60% of the land drains well, and 11% stays wet for long stretches; groundwater comes within two feet of the surface under 14% of it.
USDA rates 99% of the land very limited for a standard septic drain field, and 99% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 33% of the land floods occasionally or more, and bedrock lies within 40 inches under 74% 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 Well drained and the dominant hydrologic group is A (high infiltration, low runoff). The most common soil order is Spodosols — acidic forest soils with a distinctive leached layer, common under conifers. 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 Talkeetna and Chugach Mountains - Cook Inlet 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 |
|---|---|---|---|---|---|
| Cook Inlet Mountains-Boreal Subalpine and Alpine-Rounded Mountains, Acid | 551K | Well drained | A | Very limited | Very limited |
| Interior Alaska Mountains-Boreal Alpine-Barren Mountains | 518K | Very limited | Very limited | ||
| Cook Inlet Mountains-Boreal Alpine-Mountains | 437K | Well drained | Very limited | Very limited | |
| Cook Inlet Mountains-Boreal Alpine-Barren Mountains | 398K | Very limited | Very limited | ||
| Cook Inlet Mountains-Boreal Subalpine and Alpine-Mountains, Acid | 395K | Well drained | A | Very limited | Very limited |
| Cook Inlet Mountains-Boreal Upland and Lowland-Valleys | 296K | Well drained | A | Very limited | Very limited |
| Cook Inlet Lowlands-Boreal Upland-Till Plains | 154K | Very poorly drained | B/D | Very limited | Very limited |
| Interior Alaska Mountains-Boreal Glaciated Plains and Hills | 115K | Poorly drained | D | Very limited | Very limited |
| Interior Alaska Mountains-Boreal Alpine-Glaciated Plains and Hills | 79K | Well drained | B | Very limited | Very limited |
| Interior Alaska Mountains-Boreal Alpine-Rugged Mountains | 58K | Well drained | B | Very limited | Very limited |
| Cook Inlet Lowlands-Boreal Lowland-Flood Plains and Terraces | 53K | Somewhat poorly drained | B | Very limited | Very limited |
| Interior Alaska Mountains-Boreal Alpine-Rounded Mountains | 47K | Well drained | B | Very limited | Very limited |
| Cook Inlet Mountains-Boreal Upland-Rounded Mountains | 46K | Well drained | A | Very limited | Very limited |
| Cook Inlet Lowlands-Boreal Lowland-Flood Plains, Terraces, and Fans | 31K | Very limited | Very limited | ||
| Interior Alaska Mountains-Boreal Upland and Lowland-Mountain Valleys | 30K | Well drained | B | Very limited | Very limited |
| Cook Inlet Mountains-Boreal Subalpine and Alpine-Rounded Mountains | 24K | Well drained | A | Very limited | Very limited |
| Cook Inlet Lowlands-Boreal Lowland-Flood Plains and Terraces, Wet | 18K | Very poorly drained | B/D | Very limited | Very limited |
| Copper River Basin-Boreal Upland-Lacustrine Plains | 16K | Poorly drained | D | Very limited | Very limited |
| Southern Alaska Coastal Mountains-Maritime Alpine-Barren Mountains | 15K | Not rated | Not rated | ||
| Cook Inlet Lowlands-Boreal Upland-Glaciated Plains and Hills | 8K | Well drained | A | 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 99% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 99% 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.