Mariposa County Area, 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 Mariposa County Area, California.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Daulton very rocky loam, 15 to 30 percent slopes | 24K | Well drained | D | Very limited | Very limited |
| Ahwahnee-Auberry rocky sandy loams, 9 to 30 percent slopes | 23K | Well drained | B | Very limited | Very limited |
| Daulton loam, 15 to 30 percent slopes | 22K | Well drained | D | Very limited | Very limited |
| Bonanza-Loafercreek-Jasperpeak complex, 15 to 30 percent slopes | 21K | Well drained | D | Very limited | Very limited |
| Jasperpeak-Gopheridge complex, 30 to 60 percent slopes | 20K | Well drained | D | Very limited | Very limited |
| Daulton very rocky loam, 30 to 75 percent slopes | 19K | Well drained | D | Very limited | Very limited |
| Gardellones-Gopheridge-Motherlode complex, 30 to 60 percent slopes | 18K | Well drained | C | Very limited | Very limited |
| Blasingame-Las Posas rocky loams, 15 to 50 percent slopes | 18K | Well drained | C | Very limited | Very limited |
| Moccasinhill-Copperopolis complex, 60 to 90 percent slopes | 18K | Well drained | C | Very limited | Very limited |
| Loafercreek-Gopheridge complex, 30 to 60 percent slopes | 15K | Well drained | C | Very limited | Very limited |
| Gopheridge-Jasperpeak complex, 50 to 90 percent slopes | 14K | Well drained | C | Very limited | Very limited |
| Gopheridge-Jasperpeak-Rock outcrop complex, 30 to 60 percent slopes | 13K | Well drained | C | Very limited | Very limited |
| Trabuco-Jasperpeak-Rock outcrop complex, 8 to 30 percent slopes | 13K | Well drained | D | Very limited | Very limited |
| San Andreas-Coarsegold complex, 30 to 50 percent slopes | 12K | Well drained | C | Very limited | Very limited |
| Priestgrade channery fine sandy loam, 30 to 60 percent slopes | 11K | Well drained | D | Very limited | Very limited |
| Rock land | 10K | Very limited | Very limited | ||
| Shaver-Holland-Chawanakee complex, 8 to 30 percent slopes | 9K | Well drained | B | Very limited | Very limited |
| Ahwahnee-Auberry very rocky sandy loams, 30 to 75 percent slope | 9K | Well drained | B | Very limited | Very limited |
| Wallyhill-Fricot complex, 30 to 60 percent slopes | 9K | Well drained | C | Very limited | Very limited |
| Auberry very rocky sandy loam, 15 to 30 percent slopes | 9K | Well drained | C | Very limited | Very limited |
What This Means
Building & Foundations
About 100% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes. 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.