Animas-Dolores Area, Colorado, Parts of Archuleta, Dolores, Hinsdale, La Plata, Montezuma, San Juan, and San Miguel Counties
The dominant drainage class is 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 Animas-Dolores Area, Colorado, Parts of Archuleta, Dolores, Hinsdale, La Plata, Montezuma, San Juan, and San Miguel Counties.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Needleton-Snowdon-Rock outcrop complex, 30 to 80 percent slopes | 69K | Well drained | C | Very limited | Very limited |
| Rock outcrop | 65K | D | Very limited | Very limited | |
| Rubble land | 43K | Excessively drained | A | Very limited | Very limited |
| Snowdon-Rock outcrop complex, 30 to 65 percent slopes | 42K | Well drained | C | Very limited | Very limited |
| Rock outcrop-Snowdon complex, 45 to 75 percent slopes | 41K | D | Very limited | Very limited | |
| Whitecross-Rock outcrop complex, 45 to 75 percent slopes | 41K | Well drained | D | Very limited | Very limited |
| Graysill-Scotch complex, south aspect, 30 to 60 percent slopes | 41K | Well drained | C | Very limited | Very limited |
| Argiustolls-Haplustalfs-Rock outcrop complex, 30 to 80 percent slopes | 40K | Well drained | C | Very limited | Very limited |
| Scotch-Graysill complex, 30 to 60 percent slopes | 39K | Well drained | D | Very limited | Very limited |
| Jemco-Detra-Beje complex, 1 to 15 percent slopes | 38K | Well drained | C | Very limited | Very limited |
| Needleton-Haviland complex, 30 to 60 percent slopes | 35K | Well drained | C | Very limited | Very limited |
| Frisco-Horsethief complex, 30 to 75 percent slopes | 33K | Well drained | B | Very limited | Very limited |
| Dressel-Jersey complex, 30 to 80 percent slopes | 30K | Well drained | B | Very limited | Very limited |
| Burnson loam, 1 to 15 percent slopes | 24K | Well drained | C | Very limited | Very limited |
| Needleton stony loam, 30 to 65 percent slopes | 22K | Well drained | B | Very limited | Very limited |
| Granath-Fughes complex, 0 to 15 percent slopes | 21K | Well drained | B | Not limited | Very limited |
| Behanco-Powderhorn family complex, 0 to 15 percent slopes | 19K | Well drained | B | Not limited | Very limited |
| Frisco loam, 10 to 25 percent slopes | 15K | Well drained | B | Very limited | Very limited |
| Wauquie-Dolcan-Rock outcrop complex, 25 to 80 percent slopes | 15K | Well drained | D | Very limited | Very limited |
| Whitecross, very stony-Rock outcrop complex, 15 to 45 percent slopes | 14K | Well drained | D | Very limited | Very limited |
What This Means
Building & Foundations
About 94% 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.