Valley Area, Idaho, Parts of Adams and Valley Counties
The dominant drainage class is Somewhat excessively drained and the dominant hydrologic group is A (high infiltration, low 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 Valley Area, Idaho, Parts of Adams and Valley Counties.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Water | 35K | Not rated | Not rated | ||
| Bryan-Pyle complex, 40 to 60 percent slopes | 25K | Excessively drained | A | Very limited | Very limited |
| Pyle-Koppes complex, 40 to 60 percent slopes | 23K | Somewhat excessively drained | A | Very limited | Very limited |
| Shellrock-Rock outcrop complex, 30 to 60 percent slopes | 19K | Somewhat excessively drained | A | Very limited | Very limited |
| Jugson coarse sandy loam, 30 to 60 percent slopes | 18K | Somewhat excessively drained | B | Very limited | Very limited |
| Roseberry coarse sandy loam, occasionally flooded | 15K | Poorly drained | B | Very limited | Very limited |
| Quartzburg-Bryan complex, 10 to 45 percent slopes | 15K | Excessively drained | A | Very limited | Very limited |
| Archabal loam, 4 to 12 percent slopes | 14K | Well drained | B | Not limited | Very limited |
| McCall complex, 5 to 50 percent slopes | 10K | Somewhat excessively drained | A | Very limited | Very limited |
| Donnel sandy loam, 0 to 2 percent slopes | 10K | Well drained | A | Not limited | Very limited |
| Blackwell silt loam, frequently flooded | 8K | Very poorly drained | C/D | Very limited | Very limited |
| Archabal loam, 2 to 4 percent slopes | 8K | Well drained | B | Not limited | Very limited |
| Melton loam | 7K | Poorly drained | B/D | Very limited | Very limited |
| Gestrin loam, 2 to 4 percent slopes, rarely flooded | 7K | Moderately well drained | C | Very limited | Very limited |
| Shellrock loamy coarse sand, 35 to 60 percent slopes | 6K | Somewhat excessively drained | A | Very limited | Very limited |
| Donnel sandy loam, 2 to 4 percent slopes | 6K | Well drained | A | Not limited | Very limited |
| Rock outcrop | 5K | D | Not rated | Not rated | |
| Roseberry, occasionally flooded-Melton, frequently flooded-Jurvannah, frequently flooded complex | 5K | Poorly drained | B | Very limited | Very limited |
| Shellrock loamy coarse sand, 12 to 35 percent slopes | 5K | Somewhat excessively drained | A | Very limited | Very limited |
| Shellrock-Rock outcrop complex, 2 to 25 percent slopes | 5K | Somewhat excessively drained | A | Very limited | Very limited |
What This Means
Building & Foundations
About 68% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, poor drainage in some areas, flood-prone areas, sandy or gravelly soils with low bearing capacity. A geotechnical assessment is recommended before building.
Septic Systems
About 83% of soils are rated "very limited" for septic absorption fields. The well-drained soils may actually drain too fast for standard leach fields, allowing effluent to reach groundwater. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Soils tend to drain very quickly, meaning nutrients and water don't stick around long. Raised beds with amended soil, drip irrigation, and heavy mulching will give the best results. Compost is your best friend here — it improves water retention dramatically.