San Joaquin County, California
The dominant drainage class is Moderately 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 San Joaquin County, California.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Tokay fine sandy loam, 0 to 2 percent slopes | 32K | Well drained | A | Not limited | Very limited |
| Rindge muck, 0 to 2 percent slopes, partially drained, MLRA 16 | 31K | Very poorly drained | A/D | Very limited | Very limited |
| Merritt silty clay loam, partially drained, 0 to 2 percent slopes | 28K | Poorly drained | C | Very limited | Very limited |
| Hollenbeck silty clay, 0 to 2 percent slopes | 26K | Moderately well drained | C | Very limited | Very limited |
| Jacktone clay, 0 to 2 percent slopes | 24K | Somewhat poorly drained | D | Very limited | Very limited |
| Capay clay, 0 to 1 percent slopes, MLRA 17 | 24K | Moderately well drained | C | Very limited | Very limited |
| Veritas fine sandy loam, 0 to 2 percent slopes | 24K | Moderately well drained | A | Not limited | Somewhat limited |
| Redding gravelly loam, 0 to 8 percent slopes, dry | 24K | Moderately well drained | D | Very limited | Very limited |
| Water | 22K | D | Not rated | Not rated | |
| Archerdale clay loam, 0 to 2 percent slopes | 20K | Well drained | C | Very limited | Very limited |
| Delhi loamy sand, 0 to 2 percent slopes, MLRA 17 | 19K | Somewhat excessively drained | A | Not limited | Very limited |
| Kingile muck, partially drained, 0 to 2 percent slopes, MLRA 16 | 18K | Very poorly drained | C | Very limited | Very limited |
| Jacktone-Urban land complex, 0 to 2 percent slopes | 18K | Somewhat poorly drained | D | Very limited | Very limited |
| Stockton clay, 0 to 2 percent slopes | 17K | Somewhat poorly drained | C | Very limited | Very limited |
| Madera sandy loam, 0 to 2 percent slopes | 17K | Moderately well drained | C | Somewhat limited | Very limited |
| Tinnin loamy coarse sand, 0 to 2 percent slopes | 16K | Well drained | A | Not limited | Very limited |
| Peltier mucky clay loam, partially drained, 0 to 2 percent slopes, MLRA 16 | 16K | Poorly drained | C | Very limited | Very limited |
| Capay clay, wet, 0 percent slopes, MLRA 17 | 14K | Moderately well drained | C | Very limited | Very limited |
| Guard clay loam, drained, 0 to 2 percent slopes | 14K | Poorly drained | C | Very limited | Very limited |
| Cogna loam, 0 to 2 percent slopes | 13K | Well drained | B | Very limited | Somewhat limited |
What This Means
Building & Foundations
About 68% of soils are rated "very limited" for dwellings with basements. Specific challenges include poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 85% 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.