Okanogan National Forest Area, Washington
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 Okanogan National Forest Area, Washington.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Typic Vitricryands-Andic Haplocryods complex, till substratum, 25 to 75 percent slopes | 115K | Somewhat excessively drained | B | Very limited | Very limited |
| Lithic Dystrocryepts-Rock outcrop-Chutes, avalanche, complex, 35 to 100 percent slopes | 97K | Very limited | Very limited | ||
| Typic Vitricryands-Andic Dystrocryepts-Rock outcrop complex, 20 to 50 percent slopes | 89K | Well drained | A | Very limited | Very limited |
| Rock outcrop-Rubble land-Glaciers, snow fields, association, 15 to 100 percent slopes | 49K | Very limited | Very limited | ||
| Rock outcrop-Rubble land complex, 5 to 100 percent slopes | 41K | Very limited | Very limited | ||
| Humic Dystrocryepts-Humic Vitricryands complex, 35 to 75 percent slopes | 37K | Well drained | C | Very limited | Very limited |
| Lithic Eutrocryepts-Andic Eutrocryepts complex, 10 to 70 percent slopes | 34K | Well drained | D | Very limited | Very limited |
| Nevine-Merkel complex, 15 to 35 percent slopes | 31K | Well drained | B | Very limited | Very limited |
| Andic Eutrocryepts-Xeric Vitricryands-Rock outcrop complex, 20 to 50 percent slopes | 29K | Well drained | A | Very limited | Very limited |
| Andic Haplocryods-Typic Vitricryands, till substratum, complex, 5 to 25 percent slopes | 28K | Somewhat excessively drained | B | Somewhat limited | Somewhat limited |
| Typic Udivitrands-Andic Dystrudepts complex, till substratum, 35 to 75 percent slopes | 25K | Well drained | A | Very limited | Very limited |
| Typic Vitricryands-Andic Haplocryods-Fulvicryands association, 35 to 90 percent slopes | 24K | Well drained | A | Very limited | Very limited |
| Nevine-Wilma-Rock outcrop complex, 15 to 35 percent slopes | 24K | Well drained | B | Very limited | Very limited |
| Johntom-Foggydew-Rock outcrop complex, 35 to 75 percent slopes | 23K | Well drained | D | Very limited | Very limited |
| Andic Haplocryods-Typic Vitricryands complex, cirque basin, 10 to 50 percent slopes | 22K | Well drained | B | Very limited | Very limited |
| Myerscreek-Devore complex, 15 to 35 percent slopes | 19K | Well drained | B | Very limited | Very limited |
| Pebcreek-Brevco complex, 35 to 65 percent slopes | 18K | Well drained | A | Very limited | Very limited |
| Radercreek-Santop complex, 35 to 65 percent slopes | 17K | Well drained | A | Very limited | Very limited |
| Andic Eutrocryepts-Lithic Vitricryands complex, 15 to 35 percent slopes | 17K | Well drained | A | Very limited | Very limited |
| Shalrock-Johntom complex, 35 to 65 percent slopes | 16K | Well drained | B | Very limited | Very limited |
What This Means
Building & Foundations
About 96% 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 96% 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.