Soil drainage refers to the ability of water to flow downward through soil. Well-drained soils have sufficient surface runoff and/or downward movement of water through the soil to result in relatively short periods of saturation. Poorly drained soils have a greater frequency and duration when the soils are saturated in all or part of the root one. Soil drainage may be influenced by topography, uniformity of soil materials, proximity to the water tzable and climate.