Skagit County Area, Washington
The dominant drainage class is Moderately well drained and the dominant hydrologic group is C (slow infiltration, moderate 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 Skagit County Area, Washington.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Skagit silt loam | 26K | Poorly drained | B/D | Very limited | Very limited |
| Kindy gravelly silt loam, 30 to 65 percent slopes | 16K | Moderately well drained | C | Very limited | Very limited |
| Sumas silt loam | 15K | Poorly drained | C | Very limited | Very limited |
| Andic Xerochrepts-Rock outcrop complex, 65 to 90 percent slopes | 14K | Well drained | B | Very limited | Very limited |
| Wollard-Springsteen complex, 30 to 65 percent slopes | 14K | Moderately well drained | C | Very limited | Very limited |
| Barneston gravelly ashy loam, 0 to 8 percent slopes | 13K | Somewhat excessively drained | A | Not limited | Very limited |
| Field silt loam, protected | 12K | Moderately well drained | B | Somewhat limited | Very limited |
| Vanzandt very gravelly loam, 15 to 30 percent slopes | 11K | Moderately well drained | C | Very limited | Very limited |
| Vanzandt very gravelly loam, 0 to 15 percent slopes | 11K | Moderately well drained | C | Very limited | Very limited |
| Rinker very channery loam, 30 to 65 percent slopes | 10K | Well drained | C | Very limited | Very limited |
| Dystric Xerorthents, 50 to 80 percent slopes | 10K | Excessively drained | A | Very limited | Very limited |
| Montborne-Rinker complex, 30 to 65 percent slopes | 10K | Moderately well drained | C | Very limited | Very limited |
| Andic Cryochrepts-Rock outcrop complex, 65 to 90 percent slopes | 9K | Well drained | A | Very limited | Very limited |
| Vanzandt very gravelly loam, 30 to 65 percent slopes | 9K | Moderately well drained | C | Very limited | Very limited |
| Mt. Vernon very fine sandy loam | 9K | Moderately well drained | C | Very limited | Very limited |
| Diobsud-Crinker complex, 30 to 65 percent slopes | 9K | Moderately well drained | C | Very limited | Very limited |
| Bow gravelly loam, 0 to 3 percent slopes | 9K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Montborne very gravelly loam, 30 to 65 percent slopes | 8K | Moderately well drained | C | Very limited | Very limited |
| Montborne very gravelly silt loam, 3 to 30 percent slopes | 8K | Moderately well drained | C | Very limited | Very limited |
| Pilchuck loamy sand | 8K | Excessively drained | A | Very limited | Very limited |
What This Means
Building & Foundations
About 89% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 100% 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.