Katmai National Park and Preserve Area, Alaska
The dominant drainage class is Well drained and the dominant hydrologic group is B (moderate infiltration). 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 Katmai National Park and Preserve Area, Alaska.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Southern Alaska Peninsula Mountains-Maritime Upland-Rounded Mountains | 1.5M | Well drained | B | Very limited | Very limited |
| Southern Alaska Peninsula Mountains-Maritime Alpine-Barren Mountains | 570K | Very limited | Very limited | ||
| Bristol Bay-Northern Alaska Peninsula Lowlands-Boreal and Northwest Maritimel-Glaciated Plains, Ash Influenced | 463K | Well drained | A | Not limited | Very limited |
| Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Upland-Glaciated Plains, Ash Influenced | 343K | Very poorly drained | B | Very limited | Very limited |
| Southern Alaska Peninsula Mountains-Maritime Water, Saline | 284K | Not rated | Not rated | ||
| Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Water, Fresh | 275K | Not limited | Not limited | ||
| Southern Alaska Peninsula Mountains-Maritime Upland-Glaciated Plains and Hills | 272K | Well drained | B | Very limited | Very limited |
| Southern Alaska Peninsula Mountains-Maritime Upland-Mountains | 206K | Well drained | B | Very limited | Very limited |
| Southern Alaska Peninsula Mountains-Maritime Lowland-Flood Plains and Stream Terraces | 119K | Well drained | B | Very limited | Very limited |
| Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Upland and Boreal Upland-Glaciated Rounded Mountains | 31K | Poorly drained | A/D | Very limited | Very limited |
| Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Upland-Glaciated Rounded Mountains | 16K | Well drained | A/D | Very limited | Very limited |
| Southern Alaska Peninsula Mountains-Maritime Lowland-Coastal Plains | 4K | Very poorly drained | D | Very limited | Very limited |
What This Means
Building & Foundations
About 74% 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 86% 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.