Whatcom County Area, Washington

Survey Area WA673• Washington

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 Spodosols — acidic forest soils with a distinctive leached layer, common under conifers. 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 Whatcom 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
Whatcom-Labounty silt loams, 0 to 8 percent slopes	13K	Moderately well drained	C	Very limited	Very limited
Whatcom silt loam, 3 to 8 percent slopes	11K	Moderately well drained	C	Very limited	Very limited
Edmonds-Woodlyn loams, 0 to 2 percent slopes	10K	Somewhat poorly drained	B/D	Very limited	Very limited
Hale silt loam, drained, 0 to 2 percent slopes	10K	Somewhat poorly drained	C	Somewhat limited	Very limited
Andic Xerochrepts, 60 to 90 percent slopes	10K	Well drained	C	Very limited	Very limited
Lynden sandy loam, 0 to 3 percent slopes	10K	Well drained	A	Not limited	Very limited
Tromp loam, 0 to 2 percent slopes	9K	Moderately well drained	C	Very limited	Very limited
Shuksan-Kulshan-Rock outcrop complex, 50 to 80 percent slopes	9K	Moderately well drained	C	Very limited	Very limited
Pangborn muck, drained, 0 to 2 percent slopes	8K	Very poorly drained	C	Very limited	Very limited
Squalicum gravelly loam, 15 to 30 percent slopes	7K	Moderately well drained	B	Very limited	Very limited
Briscot silt loam, drained, 0 to 2 percent slopes	7K	Poorly drained	C	Very limited	Very limited
Whatcom silt loam, 8 to 15 percent slopes	7K	Moderately well drained	C	Very limited	Very limited
Oakes very gravelly loam, 30 to 60 percent slopes	7K	Well drained	B	Very limited	Very limited
Whitehorn silt loam, 0 to 2 percent slopes	6K	Poorly drained	C/D	Very limited	Very limited
Andic Xerochrepts-Rock outcrop complex, 60 to 90 percent slopes	6K	Well drained	C	Very limited	Very limited
Winston silt loam, 0 to 3 percent slopes	6K	Well drained	B	Not limited	Very limited
Andic Xerochrepts, cool-Rock outcrop complex, 60 to 90 percent slopes	6K	Well drained	B	Very limited	Very limited
Nati loam, 30 to 60 percent slopes	6K	Well drained	C	Very limited	Very limited
Squalicum gravelly loam, 5 to 15 percent slopes	6K	Moderately well drained	B	Somewhat limited	Very limited
Whatcom silt loam, 0 to 3 percent slopes	6K	Moderately well drained	C	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.

Spodosols

Acidic forest soils with a leached layer. Common under conifers. Often have drainage issues from a compacted subsoil layer.

Andisols

Volcanic ash soils — light, porous, and fertile. Excellent drainage, but low density can complicate foundations.

Inceptisols

Young but developing soils found in mountains and river terraces. Variable properties — check drainage and bedrock depth.

What This Means

Building & Foundations

About 80% 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.