Grant County, Washington
The most common soil here is Quincy, on about 13% of the land: a fine sand, loose sand that holds almost no water. Malaga and Renslow come next.
About 97% of the land drains well, and 2% stays wet for long stretches.
USDA rates 77% of the land very limited for a standard septic drain field, and 32% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: bedrock lies within 40 inches under 23% 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 Grant County, Washington, 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 Aridisols — dry-climate soils with limited organic matter and often calcium carbonate accumulation. 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 Grant County, Washington. 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 |
|---|---|---|---|---|---|
| Quincy fine sand, 2 to 15 percent slopes | 148K | Somewhat excessively drained | A | Somewhat limited | Very limited |
| Bakeoven-Roloff complex, 0 to 25 percent slopes | 68K | Well drained | D | Very limited | Very limited |
| Starbuck-Bakeoven-Rock outcrop complex, 0 to 45 percent slopes | 66K | Well drained | D | Very limited | Very limited |
| Renslow silt loam, 0 to 5 percent slopes | 56K | Well drained | B | Not limited | Somewhat limited |
| Quincy loamy fine sand, 0 to 15 percent slopes | 53K | Somewhat excessively drained | A | Not limited | Very limited |
| Malaga stony sandy loam, 0 to 15 percent slopes | 53K | Somewhat excessively drained | B | Not limited | Very limited |
| Renslow association | 49K | Well drained | B | Somewhat limited | Somewhat limited |
| Shano silt loam, 2 to 5 percent slopes | 45K | Well drained | B | Not limited | Somewhat limited |
| Burbank loamy fine sand, 0 to 5 percent slopes | 38K | Excessively drained | A | Not limited | Very limited |
| Malaga gravelly sandy loam, 0 to 5 percent slopes | 32K | Somewhat excessively drained | B | Not limited | Very limited |
| Malaga very stony sandy loam, 0 to 35 percent slopes | 32K | Somewhat excessively drained | B | Very limited | Very limited |
| Strat stony loam, 0 to 25 percent slopes | 30K | Well drained | B | Somewhat limited | Very limited |
| Schawana complex, 0 to 15 percent slopes | 28K | Somewhat excessively drained | D | Very limited | Very limited |
| Scoon silt loam, 0 to 5 percent slopes | 27K | Well drained | D | Very limited | Very limited |
| Zen-Lickskillet-Ralls complex, 5 to 45 percent slopes | 27K | Well drained | C | Very limited | Very limited |
| Warden silt loam, 0 to 2 percent slopes | 26K | Well drained | B | Not limited | Somewhat limited |
| Starbuck-Prosser complex, 0 to 25 percent slopes | 24K | Well drained | D | Very limited | Very limited |
| Malaga cobbly sandy loam, 0 to 15 percent slopes | 24K | Somewhat excessively drained | B | Not limited | Very limited |
| Bagdad silt loam, 5 to 20 percent slopes | 24K | Well drained | B | Somewhat limited | Somewhat limited |
| Wanser-Quincy fine sands, 0 to 5 percent slopes | 22K | Poorly drained | A/D | 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 32% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 77% 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.