A.3 NRCS Hydrologic Soil Group Definitions
| A.3 NRCS Hydrological Soil Group Definitions | ||
| Group | Meaning | Saturated HydraulicConductivity(in/hr) |
| A | Low runoff potential. Soils have high infiltration rates even when thoroughly wetted and consisting chiefly of deep, well to excessively drained sands or gravels. | ≥ 0.45 |
| B | Soils have moderate infiltration rates when thoroughly wetted and consist chiefly of moderately deep to deep, moderately well to well-drained soils with moderately fine to moderately coarse textures. E.g., shallow loess, sandy loam. | 0.30 - 0.15 |
| C | Soils h have slow infiltration rates when thoroughly wetted and consist chiefly of soils with a layer that impedes downward movement of water, or soils with moderately fine to fine textures. E.g., clay loams and shallow sandy loam. | 0.15 - 0.05 |
| D | High runoff potential. Soils having very slow infiltration rates when thoroughly wetted and consisting chiefly of clay soils with a high swelling potential, soils with a permanent high-water table, soils with a clay-pan or clay layer at or near the surface, and shallow soils over nearly impervious material. | 0.05 - 0.00 |