Mount Baker-Snoqualmie National Forest, Washington
The dominant drainage class is Well drained and the dominant hydrologic group is A (high infiltration, low 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 Mount Baker-Snoqualmie National Forest, Washington.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Typic Vitricryands-Rock outcrop association, 15 to 100 percent slopes | 366K | Well drained | A | Very limited | Very limited |
| Typic Vitricryands-Andic Dystrocryepts, cold-Rock outcrop association, 15 to 100 percent slopes | 316K | Well drained | B | Very limited | Very limited |
| Rock outcrop-Lithic Dystrocryepts-Glaciers association, 35 to 100 percent slopes | 195K | Not rated | Not rated | ||
| Andic Haplocryods-Aquic Haplocryands association, 15 to 65 percent slopes | 174K | Well drained | A | Very limited | Very limited |
| Typic Udivitrands-Aquandic Dystrudepts association, 0 to 35 percent slopes | 124K | Well drained | A | Very limited | Very limited |
| Typic Udivitrands-Oxyaquic Haplorthods association, 0 to 35 percent slopes | 89K | Well drained | A | Very limited | Very limited |
| Andic Dystrocryepts-Histic Cryaquepts-Andic Haplocryods complex association, 0 to 45 percent slopes | 64K | Well drained | A | Very limited | Very limited |
| Typic Udivitrands-Rock outcrop association, 15 to 65 percent slopes | 62K | Well drained | A | Very limited | Very limited |
| Vitrandic Humicryepts-Typic Vitricryands-Rock outcrop association, 35 to 100 percent slopes | 48K | Well drained | A | Very limited | Very limited |
| Vitrandic Humicryepts, cold-Typic Vitricryands, cold-Rock outcrop association, 35 to 100 percent slopes | 36K | Well drained | A | Very limited | Very limited |
| Andic Dystrocryepts, cold-Andic Haplocryods, cold-Rock outcrop association, 15 to 100 percent slopes | 34K | Well drained | A | Very limited | Very limited |
| Andic Haplocryods, cold-Lithic Dystrocryepts-Histic Cryaquepts association, cold, 0 to 65 percent slopes | 34K | Well drained | B | Very limited | Very limited |
| Rock outcrop-Glaciers association, 15 to 100 percent slopes | 33K | Not rated | Not rated | ||
| Andic Dystrocryepts, cold-Oxyaquic Duricryands-Lithic Dystrocryepts association, 15 to 100 percent slopes | 25K | Moderately well drained | B | Very limited | Very limited |
| Lithic Dystrocryepts-Rock outcrop-Typic Vitricryands association, 15 to 100 percent slopes | 23K | Well drained | D | Very limited | Very limited |
| Vitrandic Dystrocryepts-Histic Cryaquepts association, 0 to 15 percent slopes | 17K | Moderately well drained | C | Very limited | Very limited |
| Water | 9K | Not rated | Not rated | ||
| Vitrandic Dystrudepts-Histic Humaquepts association, 0 to 15 percent slopes | 7K | Moderately well drained | C | Very limited | Very limited |
What This Means
Building & Foundations
About 85% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes. A geotechnical assessment is recommended before building.
Septic Systems
About 85% 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.