Big Bend National Park, Texas
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 Big Bend National Park, Texas.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Corazones very gravelly sandy loam, 1 to 8 percent slopes | 92K | Well drained | A | Not limited | Not limited |
| Lingua-Rock outcrop complex, 20 to 60 percent slopes | 76K | D | Very limited | Very limited | |
| Solis-Rock outcrop complex, 1 to 20 percent slopes | 53K | D | Very limited | Very limited | |
| Corazones very gravelly sandy loam, 1 to 30 percent slopes | 48K | Well drained | A | Somewhat limited | Somewhat limited |
| Strawhouse-Stillwell complex, 1 to 8 percent slopes | 45K | Well drained | D | Very limited | Very limited |
| Blackgap-Rock outcrop complex, 20 to 70 percent slopes | 41K | Well drained | D | Very limited | Very limited |
| Chilicotal very gravelly fine sandy loam, 1 to 8 percent slopes | 38K | Well drained | B | Not limited | Somewhat limited |
| Leyva-Rock outcrop complex, 10 to 30 percent slopes | 37K | Well drained | D | Very limited | Very limited |
| Ninepoint clay loam, 0 to 3 percent slopes | 32K | Well drained | C | Somewhat limited | Very limited |
| Geefour silty clay, 3 to 20 percent slopes | 28K | Well drained | D | Very limited | Very limited |
| Blackgap-Rock outcrop complex, 10 to 30 percent slopes | 27K | Well drained | D | Very limited | Very limited |
| Geefour silty clay, 10 to 45 percent slopes | 21K | Well drained | D | Very limited | Very limited |
| Mariscal-Terlingua complex, 10 to 30 percent slopes | 21K | Well drained | D | Very limited | Very limited |
| Bissett-Rock outcrop complex, 20 to 70 percent slopes | 20K | Well drained | D | Very limited | Very limited |
| Blackgap-Rock outcrop complex, 1 to 16 percent slopes | 20K | Well drained | D | Very limited | Very limited |
| Chilicotal-Paisano association, 5 to 30 percent slopes | 19K | Well drained | B | Somewhat limited | Somewhat limited |
| Mariscal-Rock outcrop complex, 5 to 30 percent slopes | 18K | D | Very limited | Very limited | |
| Chillon very gravelly fine sandy loam, 1 to 3 percent slopes, rarely flooded | 18K | Well drained | B | Very limited | Somewhat limited |
| Solis-Rock outcrop complex, 20 to 60 percent slopes | 17K | Well drained | D | Very limited | Very limited |
| Bissett-Rock outcrop complex, 10 to 30 percent slopes | 16K | Well drained | D | Very limited | Very limited |
What This Means
Building & Foundations
About 66% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 68% 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.