Custer-Lemhi Area, Idaho, Parts of Blaine, Custer, and Lemhi Counties
The dominant drainage class is Well drained and the dominant hydrologic group is B (moderate infiltration). 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 Custer-Lemhi Area, Idaho, Parts of Blaine, Custer, and Lemhi Counties.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Calcids-Rubble land-Rock outcrop complex, 50 to 80 percent slopes | 62K | Well drained | B | Very limited | Very limited |
| Dacont-Zeebar association, 20 to 50 percent slopes | 48K | Well drained | B | Very limited | Very limited |
| Venum-Cronks complex, 20 to 50 percent slopes | 45K | Well drained | C | Very limited | Very limited |
| Dawtonia-Dacont association, 20 to 50 percent slopes | 38K | Well drained | B | Very limited | Very limited |
| Cryolls-Rubble land-Rock outcrop complex, 50 to 80 percent slopes | 36K | Well drained | C | Very limited | Very limited |
| Dawtonia-Custco association, 20 to 50 percent slopes | 32K | Well drained | C | Very limited | Very limited |
| Whitecloud-Simeroi complex, 2 to 8 percent slopes | 30K | Somewhat excessively drained | B | Not limited | Very limited |
| Ringle gravelly loam, 2 to 8 percent slopes | 28K | Somewhat excessively drained | B | Not limited | Very limited |
| Pahsimeroi gravelly loam, 2 to 6 percent slopes | 27K | Somewhat excessively drained | B | Somewhat limited | Very limited |
| Cronks-Challis association, 20 to 50 percent slopes | 27K | Well drained | C | Very limited | Very limited |
| Cryepts-Rubble land-Rock outcrop complex, 50 to 80 percent slopes | 25K | Well drained | A | Very limited | Very limited |
| Howcan-Hagenbarth-Hutchley complex, 5 to 60 percent slopes | 24K | Well drained | C | Very limited | Very limited |
| Chamberlain gravelly loam, 2 to 8 percent slopes | 23K | Well drained | C | Not limited | Very limited |
| Klug-Povey complex, 30 to 60 percent slopes | 23K | Well drained | B | Very limited | Very limited |
| Dawtonia-Frailton complex, 20 to 50 percent slopes | 21K | Well drained | C | Very limited | Very limited |
| Sparmo-Zer complex, 1 to 5 percent slopes | 20K | Well drained | B | Not limited | Somewhat limited |
| Arbus gravelly loam, 1 to 4 percent slopes | 20K | Somewhat excessively drained | B | Not limited | Very limited |
| Parkalley family-Zeebar-Primeaux association, 12 to 50 percent slopes | 20K | Well drained | C | Very limited | Very limited |
| Whiteknob gravelly loam, 2 to 8 percent slopes | 19K | Somewhat excessively drained | B | Not limited | Very limited |
| Povey-Klug, cool complex, 25 to 60 percent slopes | 18K | Well drained | B | Very limited | Very limited |
What This Means
Building & Foundations
About 71% 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 96% 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.