Alsea Area, Oregon
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 Alsea Area, Oregon.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Bohannon gravelly loam, dissected, 50 to 90 percent slopes | 40K | Well drained | B | Very limited | Very limited |
| Bohannon-Slickrock gravelly loams, dissected, 37 to 50 percent slopes | 19K | Well drained | B | Very limited | Very limited |
| Slickrock gravelly loam, 25 to 37 percent slopes | 13K | Well drained | B | Very limited | Very limited |
| Bohannon gravelly loam, dissected, 37 to 50 percent slopes | 11K | Well drained | B | Very limited | Very limited |
| Bohannon-Slickrock gravelly loams, 35 to 50 percent slopes | 7K | Well drained | B | Very limited | Very limited |
| Slickrock gravelly loam, dissected, 25 to 37 percent slopes | 6K | Well drained | B | Very limited | Very limited |
| Bohannon gravelly loam, 50 to 75 percent slopes | 6K | Well drained | B | Very limited | Very limited |
| Bohannon gravelly loam, 35 to 50 percent slopes | 6K | Well drained | B | Very limited | Very limited |
| Preacher clay loam, ridge, 0 to 25 percent slopes | 5K | Well drained | B | Somewhat limited | Very limited |
| Slickrock gravelly loam, dissected, 37 to 50 percent slopes | 4K | Well drained | B | Very limited | Very limited |
| Nehalem silt loam | 3K | Well drained | B | Very limited | Very limited |
| Slickrock gravelly loam, 37 to 50 percent slopes | 3K | Well drained | B | Very limited | Very limited |
| Colluvial and Alluvial land | 3K | Well drained | B | Somewhat limited | Somewhat limited |
| Bohannon-Slickrock gravelly loams, dissected, 25 to 37 percent slopes | 3K | Well drained | B | Very limited | Very limited |
| Bohannon gravelly loam, ridge, 25 to 37 percent slopes | 3K | Well drained | B | Very limited | Very limited |
| Bohannon loam, ridge, 5 to 25 percent slopes | 3K | Well drained | B | Very limited | Very limited |
| Water | 3K | Not rated | Not rated | ||
| Bohannon-Slickrock gravelly loams, 25 to 35 percent slopes | 2K | Well drained | B | Very limited | Very limited |
| Bohannon-Slickrock gravelly loams, dissected, 50 to 75 percent slopes | 2K | Well drained | B | Very limited | Very limited |
| Klickitat gravelly clay loam, dissected, 50 to 85 percent slopes | 2K | Well drained | B | Very limited | Very limited |
What This Means
Building & Foundations
About 92% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, flood-prone areas. 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.