Solano County, California
The dominant drainage class is Well drained and the dominant hydrologic group is D (very slow infiltration, high 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 Solano County, California.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Water | 54K | D | Not rated | Not rated | |
| Capay clay, 0 percent slopes, MLRA 17 | 38K | Moderately well drained | C | Very limited | Very limited |
| Capay silty clay loam, 0 percent slopes, MLRA 17 | 29K | Moderately well drained | C | Very limited | Very limited |
| Yolo silty clay loam, 0 to 2 percent slopes, MLRA 17 | 27K | Well drained | B | Very limited | Very limited |
| Antioch-San Ysidro complex, 0 to 2 percent slopes | 21K | Moderately well drained | D | Very limited | Very limited |
| Diablo-Ayar clays, 9 to 30 percent slopes, eroded | 21K | Well drained | C | Very limited | Very limited |
| Dibble-Los Osos clay loams, 30 to 50 percent slopes, eroded | 19K | Well drained | D | Very limited | Very limited |
| San Ysidro sandy loam, 0 to 2 percent slopes | 18K | Moderately well drained | D | Somewhat limited | Very limited |
| Clear Lake clay, 0 to 2 percent slopes, MLRA 17 | 16K | Poorly drained | C/D | Very limited | Very limited |
| Reyes silty clay | 15K | Poorly drained | D | Very limited | Very limited |
| Brentwood clay loam, 0 to 2 percent slopes | 15K | Well drained | C | Somewhat limited | Very limited |
| Tamba mucky clay, MLRA 16 | 15K | Very poorly drained | C | Very limited | Very limited |
| Dibble-Los Osos clay loams, 9 to 30 percent slopes | 14K | Well drained | D | Very limited | Very limited |
| Joice muck, MLRA 16 | 13K | Very poorly drained | A/D | Very limited | Very limited |
| Maymen-Los Gatos loams, 15 to 75 percent slopes, severe ly eroded | 13K | Somewhat excessively drained | D | Very limited | Very limited |
| Millsholm loam, 15 to 65 percent slopes, eroded, MLRA 15 | 11K | Well drained | D | Very limited | Very limited |
| Yolo loam, 0 to 4 percent slopes, MLRA 17 | 11K | Well drained | B | Very limited | Somewhat limited |
| Solano loam | 9K | Moderately well drained | D | Somewhat limited | Very limited |
| Hambright loam, 15 to 40 percent slopes | 9K | Well drained | D | Very limited | Very limited |
| Rincon clay loam, 0 to 2 percent slope | 9K | Well drained | C | Somewhat limited | Very limited |
What This Means
Building & Foundations
About 72% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 82% 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.