Yolo County, California
The dominant drainage class is Well drained and the dominant hydrologic group is C (slow infiltration, moderate 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 Yolo County, California.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Yolo silt loam, 0 to 2 percent slopes, MLRA 17 | 41K | Well drained | B | Very limited | Very limited |
| Capy silty clay, 0 percent slopes, MLRA 17 | 34K | Moderately well drained | C | Very limited | Very limited |
| Millsholm rocky loam, 15 to 75 percent slopes, eroded | 30K | Well drained | D | Very limited | Very limited |
| Rock land | 29K | Well drained | Very limited | Very limited | |
| Rincon silty clay loam | 25K | Well drained | C | Very limited | Very limited |
| Sacramento clay, 0 to 2 percent slopes, MLRA 17 | 23K | Poorly drained | C/D | Very limited | Very limited |
| Brentwood silty clay loam, 0 to 2 percent slopes | 23K | Well drained | C | Very limited | Very limited |
| Corning gravelly loam, 0 to 12 percent slopes, MLRA 17 | 22K | Well drained | C | Somewhat limited | Very limited |
| Marvin silty clay loam | 21K | Somewhat poorly drained | C | Very limited | Very limited |
| Dibble clay loam, 14 to 55 percent slopes, eroded, MLRA 15 | 18K | Well drained | D | Very limited | Very limited |
| Sehorn-Balcom complex, 15 to 30 percent slopes, eroded | 18K | Well drained | D | Very limited | Very limited |
| Balcom-Dibble complex, 30 to 50 percent slopes, eroded | 16K | Well drained | C | Very limited | Very limited |
| Tehama loam, 0 to 2 percent slopes, loamy substratum, MLRA 17 | 16K | Well drained | C | Somewhat limited | Very limited |
| Sehorn-Balcom complex, 2 to 15 percent slopes | 16K | Well drained | C | Very limited | Very limited |
| Balcom silty clay loam, 30 to 50 percent slopes, eroded | 12K | Well drained | C | Very limited | Very limited |
| Sacramento clay, 0 to 2 percent slopes, dry, MLRA 16 | 12K | Poorly drained | C/D | Very limited | Very limited |
| Sacramento soils, flooded | 12K | Poorly drained | D | Very limited | Very limited |
| Clear Lake soils, flooded | 12K | Poorly drained | C/D | Very limited | Very limited |
| Sehorn-Balcom complex, 30 to 50 percent slopes, eroded | 11K | Well drained | D | Very limited | Very limited |
| Capay soils, overwash, 0 percent slopes, frequently flooded, MLRA 17 | 11K | Moderately well drained | C | Very limited | Very limited |
What This Means
Building & Foundations
About 90% 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 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.