Cobb County, Georgia
The most common soil here is Madison, on about 26% of the land: a gravelly sandy loam, gritty and crumbly. Gwinnett and Appling come next.
About 81% of the land drains well, and 6% stays wet for long stretches; groundwater comes within two feet of the surface under 6% of it.
USDA rates 32% 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: 11% of the land floods occasionally or more, and bedrock lies within 40 inches under 11% 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 Cobb County, Georgia, 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 Ultisols — strongly weathered soils with clay-enriched subsoils, common in warm humid climates. 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 Cobb County, Georgia. 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 |
|---|---|---|---|---|---|
| Gwinnett clay loam, 6 to 10 percent slopes, severely eroded | 13K | Well drained | B | Not limited | Somewhat limited |
| Madison and Pacolet soils, 10 to 15 percent slopes, severely eroded | 13K | Well drained | B | Somewhat limited | Somewhat limited |
| Madison clay loam, 6 to 10 percent slopes, severely eroded | 12K | Well drained | B | Not limited | Somewhat limited |
| Madison and Pacolet soils, 15 to 25 percent slopes, eroded | 12K | Well drained | B | Very limited | Very limited |
| Cartecay fine sandy loam, 0 to 2 percent slopes, frequently flooded | 10K | Somewhat poorly drained | A/D | Very limited | Very limited |
| Madison sandy loam, 2 to 6 percent slopes, moderately eroded | 9K | Well drained | B | Not limited | Somewhat limited |
| Appling sandy loam, 6 to 10 percent slopes | 9K | Well drained | B | Not limited | Somewhat limited |
| Gwinnett clay loam, 10 to 15 percent slopes, severely eroded | 8K | Well drained | B | Somewhat limited | Somewhat limited |
| Toccoa sandy loam, 0 to 2 percent slopes, occasionally flooded | 8K | Moderately well drained | A | Very limited | Very limited |
| Cecil sandy loam, 2 to 6 percent slopes, moderately eroded | 7K | Well drained | B | Not limited | Somewhat limited |
| Appling sandy loam, 2 to 6 percent slopes | 7K | Well drained | B | Not limited | Somewhat limited |
| Gwinnett clay loam, 2 to 6 percent slopes, severely eroded | 6K | Well drained | B | Not limited | Somewhat limited |
| Musella and Pacolet stony soils, 10 to 45 percent slopes | 6K | Well drained | D | Very limited | Very limited |
| Madison sandy loam, 6 to 10 percent slopes, eroded | 6K | Well drained | B | Not limited | Somewhat limited |
| Cecil sandy loam, 6 to 10 percent slopes, moderately eroded | 6K | Well drained | B | Not limited | Somewhat limited |
| Madison sandy loam, 10 to 15 percent slopes, eroded | 5K | Well drained | B | Somewhat limited | Somewhat limited |
| Gwinnett clay loam, 15 to 25 percent slopes, eroded | 4K | Well drained | B | Very limited | Very limited |
| Pacolet sandy clay loam, 6 to 10 percent slopes, severely eroded | 4K | Well drained | B | Not limited | Somewhat limited |
| Madison clay loam, 15 to 25 percent slopes, severely eroded | 4K | Well drained | B | Very limited | Very limited |
| Louisa soils, 25 to 60 percent slopes | 4K | Somewhat excessively drained | 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 32% 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.