Washington County, Tennessee
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 Washington County, Tennessee.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Dewey-Collegedale complex, 6 to 15 percent slopes, severely eroded | 40K | Well drained | B | Somewhat limited | Somewhat limited |
| Dewey-Collegedale complex, 15 to 25 percent slopes, severely eroded | 29K | Well drained | B | Very limited | Very limited |
| Dewey-Udorthents-Urban land complex, 5 to 20 percent slopes | 16K | Well drained | B | Very limited | Very limited |
| Greendale silt loam, 0 to 6 percent slopes, rarely flooded | 10K | Well drained | B | Very limited | Somewhat limited |
| Bowmantown silt loam, 6 to 12 percent slopes | 8K | Moderately well drained | C | Very limited | Very limited |
| Unicoi-Rock outcrop complex, 50 to 80 percent slopes | 6K | Somewhat excessively drained | D | Very limited | Very limited |
| Urban land-Udorthents complex | 6K | Not rated | Not rated | ||
| Talbott-Rock outcrop-Bradyville complex, 12 to 20 percent slopes, eroded | 5K | Well drained | C | Very limited | Very limited |
| Montevallo channery silt loam, 35 to 50 percent slopes | 4K | Well drained | D | Very limited | Very limited |
| Montevallo channery silt loam, 50 to 80 percent slopes | 4K | Well drained | D | Very limited | Very limited |
| Cataska channery silt loam, 50 to 80 percent slopes | 4K | Excessively drained | D | Very limited | Very limited |
| Montevallo channery silt loam, 12 to 20 percent slopes | 4K | Well drained | D | Very limited | Very limited |
| Lindside silt loam, 0 to 3 percent slopes, occasionally flooded, warm | 4K | Moderately well drained | C | Very limited | Very limited |
| Talbott-Rock outcrop-Bradyville complex, 20 to 50 percent slopes, eroded | 3K | Well drained | C | Very limited | Very limited |
| Dewey-Collegedale complex, 25 to 40 percent slopes, severely eroded | 3K | Well drained | B | Very limited | Very limited |
| Waynesboro loam, 6 to 15 percent slopes, eroded | 2K | Well drained | B | Somewhat limited | Somewhat limited |
| Water 1982 NRI | 2K | Not rated | Not rated | ||
| Nolichucky loam, 5 to 12 percent slopes, eroded | 2K | Well drained | B | Somewhat limited | Somewhat limited |
| Keener loam, 5 to 12 percent slopes | 2K | Well drained | B | Somewhat limited | Very limited |
| Northcove stony sandy loam, 50 to 80 percent slopes | 2K | Well drained | A | Very limited | Very limited |
What This Means
Building & Foundations
About 65% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 60% 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.