Madison County Area, Idaho
The most common soil here is Ririe, on about 16% of the land: a silt loam, smooth, like flour. Rexburg and Tetonia come next.
About 78% of the land drains well, and 12% stays wet for long stretches; groundwater comes within two feet of the surface under 4% of it.
USDA rates 44% of the land very limited for a standard septic drain field, and 30% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 5% of the land floods occasionally or more, and bedrock lies within 40 inches under 15% 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 Madison County Area, Idaho, 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 B (moderate infiltration). The most common soil order is Mollisols — grassland soils with a thick, dark, fertile topsoil rich in organic matter. 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 Madison County Area, Idaho. 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 |
|---|---|---|---|---|---|
| Ririe silt loam, 4 to 8 percent slopes | 22K | Well drained | B | Not limited | Somewhat limited |
| Rexburg silt loam, 4 to 8 percent slopes | 18K | Well drained | B | Not limited | Somewhat limited |
| Tetonia-Ririe silt loams, 4 to 12 percent slopes | 15K | Well drained | B | Not limited | Somewhat limited |
| Rexburg silt loam, 2 to 4 percent slopes | 12K | Well drained | B | Not limited | Somewhat limited |
| Haplaquolls, channeled | 9K | Poorly drained | C/D | Very limited | Very limited |
| Blackfoot silt loam | 8K | Somewhat poorly drained | C | Very limited | Very limited |
| Mathon-Rock outcrop-Modkin complex, 0 to 12 percent slopes | 8K | Well drained | A | Very limited | Very limited |
| Eginbench loamy coarse sand, wet | 8K | Somewhat poorly drained | A | Very limited | Very limited |
| Ririe silt loam, 8 to 12 percent slopes | 8K | Well drained | B | Somewhat limited | Somewhat limited |
| Greys silt loam, 20 to 30 percent slopes | 7K | Well drained | C | Very limited | Very limited |
| Mathon-Rock outcrop complex, 2 to 20 percent slopes | 7K | Well drained | A | Somewhat limited | Somewhat limited |
| Panmod silt loam, 4 to 12 percent slopes | 6K | Well drained | C | Not limited | Very limited |
| Withers silty clay loam | 6K | Somewhat poorly drained | C | Somewhat limited | Very limited |
| Annis silty clay loam | 6K | Moderately well drained | C | Somewhat limited | Very limited |
| Labenzo silt loam | 6K | Moderately well drained | A | Somewhat limited | Very limited |
| Ririe-Rexburg silt loams, 4 to 12 percent slopes | 6K | Well drained | B | Not limited | Somewhat limited |
| Bannock loam | 5K | Well drained | B | Not limited | Somewhat limited |
| Lantonia silt loam, 4 to 12 percent slopes | 5K | Well drained | B | Not limited | Somewhat limited |
| Rexburg silt loam, 0 to 2 percent slopes | 5K | Well drained | B | Not limited | Somewhat limited |
| Tetonia silt loam, 8 to 12 percent slopes | 4K | Well drained | B | Somewhat limited | Somewhat 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 30% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 44% of soils have significant septic limitations, while others are more suitable. A perc test is essential — conditions vary across the area.
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.