Anchorage 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 Anchorage Area, Alaska.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Nakochna-Rock outcrop association, 20 to 85 percent slopes | 26K | Well drained | D | Very limited | Very limited |
| Cryorthents and Urban land, 0 to 5 percent slopes | 23K | Not rated | Not rated | ||
| Talkeetna-Chugach-Histic Cryaquepts association, cool, 10 to 70 percent slopes | 16K | Well drained | B | Very limited | Very limited |
| Cryorthents and Urban land, 5 to 20 percent slopes | 15K | Not rated | Not rated | ||
| Deception-Estelle-Kichatna complex, undulating and hilly | 14K | Well drained | B | Somewhat limited | Somewhat limited |
| Andic Humicryods-Rock outcrop association, 25 to 85 percent slopes | 13K | Well drained | B | Very limited | Very limited |
| Hurdygurdy-Siwash-Rock outcrop association, 10 to 70 percent slopes | 11K | Well drained | B | Very limited | Very limited |
| Talkeetna-Chugach-Histic Cryaquepts association, 10 to 70 percent slopes | 10K | Well drained | B | Very limited | Very limited |
| Water, fresh | 9K | Not rated | Not rated | ||
| Kashwitna-Kichatna complex, 0 to 3 percent slopes | 9K | Well drained | B | Not limited | Very limited |
| Typic Cryaquent and Typic Cryaquept soils, 0 to 2 percent slopes | 8K | Very poorly drained | D | Very limited | Very limited |
| Deception-Estelle-Kichatna complex, 45 to 85 percent slopes | 8K | Well drained | B | Very limited | Very limited |
| Deception-Estelle-Kichatna complex, undulating and steep | 7K | Well drained | B | Very limited | Very limited |
| Talkeetna-Chugach-Deneka complex, 20 to 45 percent slopes | 7K | Well drained | B | Very limited | Very limited |
| Deception-Estelle-Kichatna complex, 20 to 45 percent slopes | 7K | Well drained | B | Very limited | Very limited |
| Talkeetna-Chugach-Deneka complex, 45 to 85 percent slopes | 7K | Well drained | B | Very limited | Very limited |
| Deception-Estelle-Kichatna complex, 0 to 7 percent slopes | 7K | Well drained | B | Not limited | Somewhat limited |
| Kashwitna-Kichatna complex, undulating and steep | 6K | Well drained | B | Very limited | Very limited |
| Moose River-Niklason complex, occasionally flooded, 0 to 3 percent slopes | 6K | Very poorly drained | D | Very limited | Very limited |
| Kashwitna-Kichatna complex, 30 to 85 percent slopes | 5K | Well drained | B | Very limited | Very limited |
What This Means
Building & Foundations
About 64% 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 68% 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.