North Cascades National Park Complex, 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 North Cascades National Park Complex, Washington.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Rock outcrop-Glaciers-Harlequin complex, 25 to 100 percent slopes | 144K | Very limited | Very limited | ||
| Doubtful-Treen-Rock outcrop complex, 35 to 100 percent slopes | 73K | Well drained | D | Very limited | Very limited |
| Doubtful-Triumph-Perfect complex, 35 to 100 percent slopes | 68K | Well drained | B | Very limited | Very limited |
| Mox-Doubtful-Perfect complex, 35 to 100 percent slopes | 55K | Well drained | A | Very limited | Very limited |
| Stetattle-Doubtful-Arriva complex, 15 to 100 percent slopes | 52K | Well drained | B | Very limited | Very limited |
| Spickard-Tepeh-Maggib complex, 15 to 100 percent slopes | 52K | Well drained | A | Very limited | Very limited |
| Thorton-Ragged-Benzarino complex, 35 to 100 percent slopes | 37K | Well drained | A | Very limited | Very limited |
| Stetattle-Forbidden-Triumph complex, 15 to 65 percent slopes | 22K | Well drained | A | Very limited | Very limited |
| Despair-Goode-Rock outcrop complex, 35 to 100 percent slopes | 18K | Well drained | A | Very limited | Very limited |
| Rock outcrop-Despair complex, 35 to 100 percent slopes | 18K | Very limited | Very limited | ||
| Water | 17K | Not rated | Not rated | ||
| Thorton-Ragged-Ledeir complex, 15 to 65 percent slopes | 14K | Well drained | A | Very limited | Very limited |
| Benzarino-Ragged-Rock outcrop complex, 35 to 100 percent slopes | 11K | Well drained | D | Very limited | Very limited |
| Tricouni-Ragged-Easy complex, 5 to 50 percent slopes | 11K | Well drained | A | Very limited | Very limited |
| Stehekin-Primus-Stetattle complex, 35 to 100 percent slopes | 10K | Well drained | A | Very limited | Very limited |
| Noca-Perfect complex, 35 to 100 percent slopes | 10K | Well drained | A | Very limited | Very limited |
| Farway-Sawtooth-Despair complex, 35 to 100 percent slopes | 10K | Well drained | A | Very limited | Very limited |
| Chilliwack-Perfect-Terror complex, 15 to 65 percent slopes | 10K | Well drained | A | Very limited | Very limited |
| Perfect-Spickard-Stetattle complex, 15 to 65 percent slopes | 8K | Well drained | A | Very limited | Very limited |
| Chilliwack-Forbidden-Stetattle complex, 15 to 65 percent slopes | 6K | Well drained | A | Very limited | Very limited |
What This Means
Building & Foundations
About 97% 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 97% 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.