Skagit County Area, Washington
The most common soil here is Vanzandt, on about 5% of the land. Kindy and Barneston come next.
About 40% of the land drains well, and 16% stays wet for long stretches; groundwater comes within two feet of the surface under 19% of it.
USDA rates 98% of the land very limited for a standard septic drain field, and 89% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 8% of the land floods occasionally or more, and bedrock lies within 40 inches under 22% of it.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The soils you're most likely standing on
The biggest named soils in Skagit County Area, Washington, each drawn five feet deep from its official USDA description, in its recorded colors.
Dots mark gravel; white flecks mark lime. Shares are by acres across the survey area, and each mapped patch usually mixes several of these soils.
The biggest mapped areas
The dominant drainage class is Moderately well drained and the dominant hydrologic group is C (slow infiltration, moderate runoff). The most common soil order is Andisols — soils formed in volcanic ash, very light and porous. 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. Search your address to find the exact soil composition, drainage, and series details at your specific location.
| 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 |
Soil Orders in This Area
The USDA classifies every soil into one of 12 soil orders. Here are the dominant orders found in this survey area.
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 98% 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.