Middle Fork Payette River Area, Idaho, Parts of Valley and Boise Counties
The most common soil here is Koppes, on about 18% of the land: a coarse sand, loose sand that holds almost no water. Coski and Pyle come next.
About 98% of the land drains well.
USDA rates 99% of the land very limited for a standard septic drain field, and 98% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 1% of the land floods occasionally or more, and bedrock lies within 40 inches under 57% of it.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The soils you're most likely standing on
The biggest named soils in Middle Fork Payette River Area, Idaho, Parts of Valley and Boise Counties, each drawn five feet deep from its official USDA description, in its recorded colors.
Dots mark gravel; white flecks mark lime. Shares are by acres across the survey area, and each mapped patch usually mixes several of these soils.
The biggest mapped areas
The dominant drainage class is Well drained and the dominant hydrologic group is A (high infiltration, low runoff). The most common soil order is Inceptisols — young soils with minimal horizon development but more than Entisols. 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 Middle Fork Payette River Area, Idaho, Parts of Valley and Boise Counties. Search your address to find the exact soil composition, drainage, and series details at your specific location.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Quartzburg-Coski complex, 25 to 70 percent slopes | 29K | Somewhat excessively drained | A | Very limited | Very limited |
| Pyle-Koppes complex, 40 to 60 percent slopes | 25K | Somewhat excessively drained | A | Very limited | Very limited |
| Koppes-Scriver complex, 40 to 60 percent slopes | 22K | Well drained | A | Very limited | Very limited |
| Koppes-Quartzburg gravelly loamy coarse sands, 40 to 60 percent slopes | 21K | Well drained | A | Very limited | Very limited |
| Koppes-Toiyabe gravelly loamy coarse sands, 40 to 60 percent slopes | 21K | Well drained | A | Very limited | Very limited |
| Bryan-Pyle complex, 40 to 60 percent slopes | 19K | Excessively drained | A | Very limited | Very limited |
| Coski complex, 40 to 60 percent slopes | 17K | Well drained | A | Very limited | Very limited |
| Pyle-Quartzburg complex, 40 to 60 percent slopes | 11K | Somewhat excessively drained | A | Very limited | Very limited |
| Hanks-Bryan gravelly coarse sandy loams, 40 to 60 percent slopes | 7K | Well drained | A | Very limited | Very limited |
| Scriver-Bryan complex, 40 to 60 percent slopes | 7K | Well drained | A | Very limited | Very limited |
| Graylock-Whitecap complex, 40 to 60 percent slopes | 7K | Well drained | A | Very limited | Very limited |
| Hanks-Josie gravelly coarse sandy loams, 40 to 60 percent slopes | 6K | Well drained | A | Very limited | Very limited |
| Graylock, very stony surface-Koppes complex, 40 to 60 percent slopes | 6K | Well drained | A | Very limited | Very limited |
| Pyle-Ligget complex, 40 to 60 percent slopes | 6K | Somewhat excessively drained | A | Very limited | Very limited |
| Coski-Scriver complex, 20 to 40 percent slopes | 6K | Well drained | A | Very limited | Very limited |
| Josie gravelly coarse sandy loam, 40 to 60 percent slopes | 6K | Well drained | A | Very limited | Very limited |
| Hanks gravelly coarse sandy loam, 20 to 40 percent slopes | 6K | Well drained | A | Very limited | Very limited |
| Koppes-Whitecap gravelly loamy coarse sands, 20 to 40 percent slopes | 6K | Well drained | A | Very limited | Very limited |
| Pyle-Scriver complex, 20 to 40 percent slopes | 5K | Somewhat excessively drained | A | Very limited | Very limited |
| Koppes-Josie complex, 40 to 60 percent slopes | 5K | Well drained | A | Very limited | Very limited |
Soil Orders in This Area
The USDA classifies every soil into one of 12 soil orders. Here are the dominant orders found in this survey area.
What This Means
Building & Foundations
About 98% 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 99% 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.