Joint Base Lewis-McChord Area, Washington, Parts of Pierce and Thurston Counties
The dominant drainage class is Somewhat excessively drained and the dominant hydrologic group is A (high infiltration, low runoff). The most common soil order is Inceptisols — young soils with minimal horizon development but more than Entisols. 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 Joint Base Lewis-McChord Area, Washington, Parts of Pierce and Thurston Counties. 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 |
|---|---|---|---|---|---|
| Spanaway gravelly sandy loam, 0 to 3 percent slopes | 31K | Somewhat excessively drained | A | Somewhat limited | Very limited |
| McChord-Everett complex, 3 to 15 percent slopes | 10K | Moderately well drained | A | Very limited | Very limited |
| Spanaway gravelly sandy loam, 3 to 15 percent slopes | 8K | Somewhat excessively drained | A | Somewhat limited | Very limited |
| Urban land-Spanaway complex, 0 to 2 percent slopes | 7K | Not rated | Not rated | ||
| Everett-Spanaway complex, 3 to 15 percent slopes | 4K | Somewhat excessively drained | A | Not limited | Very limited |
| Everett-Spanaway-Spana complex, 0 to 30 percent slopes | 3K | Somewhat excessively drained | A | Very limited | Very limited |
| Urban land | 3K | Not rated | Not rated | ||
| Nisqually loamy fine sand, 0 to 3 percent slopes | 3K | Somewhat excessively drained | A | Not limited | Very limited |
| Everett very gravelly sandy loam, 2 to 40 percent slopes | 2K | Somewhat excessively drained | A | Very limited | Very limited |
| Yelm-Steilacoom-Everett complex, 0 to 30 percent slopes | 2K | Moderately well drained | B/D | Very limited | Very limited |
| Xerorthents, 30 to 100 percent slopes | 2K | Somewhat excessively drained | A | Very limited | Very limited |
| Everett very gravelly sandy loam, 0 to 8 percent slopes | 1K | Somewhat excessively drained | A | Not limited | Very limited |
| McChord-Everett complex, 15 to 30 percent slopes | 1K | Moderately well drained | A | Very limited | Very limited |
| Spana-Spanaway-Nisqually complex, 0 to 2 percent slopes | 1K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Semiahmoo-Water complex, 0 to 1 percent slopes | 1K | Very poorly drained | B/D | Very limited | Very limited |
| Water, fresh | 1K | Not rated | Not rated | ||
| McChord-Everett complex, 0 to 3 percent slopes | 908 | Moderately well drained | A | Very limited | Very limited |
| Pilchuck loamy sand, 0 to 3 percent slopes | 775 | Somewhat excessively drained | A | Very limited | Very limited |
| Indianola-Yelm complex, 0 to 30 percent slopes | 757 | Somewhat excessively drained | A | Very limited | Very limited |
| Semiahmoo muck, 0 to 1 percent slopes | 677 | Very poorly drained | B/D | 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 31% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 86% of soils are rated "very limited" for septic absorption fields. The well-drained soils may actually drain too fast for standard leach fields, allowing effluent to reach groundwater. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Soils tend to drain very quickly, meaning nutrients and water don't stick around long. Raised beds with amended soil, drip irrigation, and heavy mulching will give the best results. Compost is your best friend here — it improves water retention dramatically.