Yolo County, California
The most common soil here is Sacramento, on about 8% of the land. Capay and Yolo come next.
About 57% of the land drains well, and 32% stays wet for long stretches; groundwater comes within two feet of the surface under 14% of it.
USDA rates 96% of the land very limited for a standard septic drain field, and 86% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 10% of the land floods occasionally or more, and bedrock lies within 40 inches under 27% of it.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The soils you're most likely standing on
The biggest named soils in Yolo County, California, each drawn five feet deep from its official USDA description, in its recorded colors.
Dots mark gravel; white flecks mark lime. Shares are by acres across the survey area, and each mapped patch usually mixes several of these soils.
The biggest mapped areas
The dominant drainage class is Well drained and the dominant hydrologic group is C (slow infiltration, moderate 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 Yolo County, California. 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 |
|---|---|---|---|---|---|
| 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 |
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 86% 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 96% 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.