Sacramento County, California
The most common soil here is San Joaquin, on about 18% of the land: a loam, a balanced mix that crumbles in your hand. Redding and Gazwell come next.
About 27% of the land drains well, and 25% stays wet for long stretches; groundwater comes within two feet of the surface under 27% of it.
USDA rates 87% of the land very limited for a standard septic drain field, and 75% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 5% of the land floods occasionally or more, and bedrock lies within 40 inches under 11% 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 Sacramento 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 Moderately well drained and the dominant hydrologic group is D (very slow infiltration, high runoff). The most common soil order is Alfisols — moderately leached forest soils with a clay-enriched subsoil. 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 Sacramento 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 |
|---|---|---|---|---|---|
| San Joaquin silt loam, leveled, 0 to 1 percent slopes | 55K | Moderately well drained | C | Very limited | Very limited |
| Redding gravelly loam, 0 to 8 percent slopes, MLRA 17 | 31K | Moderately well drained | D | Very limited | Very limited |
| San Joaquin silt loam, 0 to 3 percent slopes | 29K | Moderately well drained | C | Very limited | Very limited |
| Gazwell mucky clay, partially drained, 0 to 2 percent slopes | 24K | Very poorly drained | B/D | Very limited | Very limited |
| Water | 22K | D | Not rated | Not rated | |
| Urban land-Xerarents-Fiddyment complex, 0 to 8 percent slopes | 21K | D | Not limited | Not limited | |
| Hadselville-Pentz complex, 2 to 30 percent slopes | 19K | Moderately well drained | D | Very limited | Very limited |
| Clear Lake clay, hardpan substratum, drained, 0 to 1 percent slopes | 17K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Xerorthents, dredge tailings, 2 to 50 percent slopes | 17K | Somewhat excessively drained | A | Very limited | Very limited |
| Egbert clay, partially drained, 0 to 2 percent slopes | 15K | Poorly drained | C/D | Very limited | Very limited |
| San Joaquin-Urban land complex, 0 to 2 percent slopes | 14K | Moderately well drained | C | Very limited | Very limited |
| Corning complex, 0 to 8 percent slopes | 14K | Well drained | D | Somewhat limited | Very limited |
| Urban land | 13K | D | Not limited | Not limited | |
| Whiterock loam, 3 to 30 percent slopes | 10K | Somewhat excessively drained | D | Very limited | Very limited |
| Sailboat silt loam, partially drained, 0 to 2 percent slopes, MLRA 16 | 10K | Somewhat poorly drained | C | Very limited | Very limited |
| San Joaquin-Galt complex, leveled, 0 to 1 percent slopes | 10K | Moderately well drained | D | Very limited | Very limited |
| Rindge mucky silt loam, partially drained, 0 to 2 percent slopes, MLRA 16 | 9K | Very poorly drained | A/D | Very limited | Very limited |
| Scribner clay loam, partially drained, 0 to 2 percent slopes, MLRA 16 | 9K | Poorly drained | C | Very limited | Very limited |
| San Joaquin silt loam, 3 to 8 percent slopes | 9K | Moderately well drained | C | Very limited | Very limited |
| Xerarents-Urban land-San Joaquin complex, 0 to 5 percent slopes | 9K | Well drained | Not limited | Not 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 75% 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 87% 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
Drainage is generally favorable for gardening. Adding compost and mulch will improve fertility and water retention. Test your soil's pH before planting — most vegetables prefer 6.0-7.0.