Which soil texture typically has the fastest drainage?

• A. Gravel
• B. Sand
• C. Silt
• D. Clay

Answer: (B)

Drainage in soil depends on how big and well-connected the pore spaces are. Water moves more easily through larger pores, so soils with coarser textures drain faster. Clay has very small pores and high capillary suction, so it holds water and drains slowly. Silt has intermediate-sized pores and drains more slowly than coarse textures. Sand has larger grains and bigger, better-connected pore spaces, allowing water to drain more quickly under gravity and with less capillary retention. While gravel would drain even faster due to even larger voids, among the standard soil textures listed, sand typically shows the fastest drainage.