Dinosaur National Monument, Colorado and Utah
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 Dinosaur National Monument, Colorado and Utah.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Rock outcrop, Torriorthents, and Ustorthents soils, 25 to 75 percent slopes, rubbly | 51K | Well drained | D | Very limited | Very limited |
| Rock outcrop | 14K | D | Very limited | Very limited | |
| Cragnot-Pensore-Grapit association, 6 to 75 percent slopes, very stony | 14K | Well drained | B | Very limited | Very limited |
| Ustorthents, frigid-Borolls complex, 25 to 75 percent slopes, rubbly | 12K | Well drained | C | Very limited | Very limited |
| Rock outcrop-Ustochrepts-Cryochrepts complex, 50 to 90 percent slopes, extremely stony | 11K | D | Very limited | Very limited | |
| Rock outcrop-Hackling complex, 10 to 45 percent slopes, very stony | 8K | D | Very limited | Very limited | |
| Arches-Mespun-Rock outcrop complex, 4 to 40 percent slopes | 7K | Excessively drained | D | Very limited | Very limited |
| Strych-Mellenthin complex, 3 to 45 percent slopes, very bouldery | 7K | Well drained | A | Very limited | Very limited |
| Cortyzack-Duffymont, rubbly complex, 3 to 25 percent slopes | 5K | Well drained | B | Somewhat limited | Somewhat limited |
| Stout-Rock outcrop complex, 5 to 35 percent slopes, very stony | 5K | Somewhat excessively drained | D | Very limited | Very limited |
| Pensore-Lodore-Rock outcrop complex, 3 to 45 percent slopes, very stony | 4K | Well drained | D | Very limited | Very limited |
| Pensore-Roto complex, 3 to 45 percent slopes, very stony | 4K | Well drained | D | Very limited | Very limited |
| Strell-Rock outcrop-Marthaspeak complex, 3 to 45 percent slopes | 4K | Somewhat excessively drained | D | Very limited | Very limited |
| Holter-Detra family complex, 3 to 25 percent slopes, extremely stony | 4K | Well drained | C | Very limited | Very limited |
| Splimo-Chew-Rock outcrop complex, 10 to 50 percent slopes, extremely flaggy | 4K | Well drained | D | Very limited | Very limited |
| Rizno-Windcomb-ThumbRock complex, 3 to 25 percent slopes, extremely flaggy | 3K | Well drained | D | Very limited | Very limited |
| Schoonover-Duffymont complex, 3 to 25 percent slopes, rubbly | 3K | Well drained | D | Very limited | Very limited |
| Mantlemine loam, 1 to 8 percent slopes | 3K | Well drained | B | Not limited | Somewhat limited |
| Lakebench-Yampa complex, 5 to 30 percent slopes, very stony | 3K | Well drained | A | Very limited | Very limited |
| Water | 3K | Not rated | Not rated |
What This Means
Building & Foundations
About 93% 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 93% 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.