Denali National Park and Preserve Area, Alaska
The dominant drainage class is Poorly drained and the dominant hydrologic group is D (very slow infiltration, high runoff). 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 Denali National Park and Preserve Area, Alaska.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Nonvegetated Mountains, South Central Mountains | 1.1M | Very limited | Very limited | ||
| Nonvegetated Mountains, Alaska Mountains | 714K | Very limited | Very limited | ||
| Boreal Loess Plains, Hills, and Drains with Continuous Permafrost | 145K | Poorly drained | D | Very limited | Very limited |
| Boreal Loess Plains and Peat Plateaus with Continuous Permafrost | 143K | Poorly drained | D | Very limited | Very limited |
| Boreal Terraces with Discontinuous Permafrost | 136K | Poorly drained | D | Very limited | Very limited |
| Boreal Loess Plains with Continuous Permafrost | 124K | Poorly drained | C/D | Very limited | Very limited |
| Alpine Till Plains and Hills with Discontinuous Permafrost | 116K | Well drained | A | Very limited | Very limited |
| Alpine Mountains | 112K | Well drained | B | Very limited | Very limited |
| Alpine Dark Sedimentary Mountains, High Elevation | 109K | Well drained | C | Very limited | Very limited |
| Boreal Loess Plains and Hills with Continuous Permafrost | 105K | Poorly drained | D | Very limited | Very limited |
| Alpine Schist Mountains with Discontinuous Permafrost | 93K | Well drained | C | Very limited | Very limited |
| Boreal Terraces with Continuous Permafrost, Very Wet | 91K | Poorly drained | C/D | Very limited | Very limited |
| Alpine Mixed Lithology Mountains, High Elevation | 87K | Well drained | B | Very limited | Very limited |
| Alpine Till Plains with Discontinuous Permafrost | 86K | Poorly drained | D | Very limited | Very limited |
| Boreal Terraces with Continuous Permafrost | 85K | Poorly drained | D | Very limited | Very limited |
| Boreal Eolian Plains and Dunes with Discontinuous Permafrost | 79K | Poorly drained | D | Very limited | Very limited |
| Boreal Groundwater Discharge Plains with Discontinuous Permafrost | 74K | Poorly drained | A/D | Very limited | Very limited |
| Boreal Flood Plains with Discontinuous Permafrost | 70K | Well drained | B | Very limited | Very limited |
| Boreal and Subalpine Schist Mountain Valleys | 69K | Poorly drained | B/D | Very limited | Very limited |
| Boreal Terraces and High Flood Plains with Continuous Permafrost | 69K | Poorly drained | D | Very limited | Very limited |
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.