drainage pattern

In geomorphology, a drainage system is the pattern formed by the streams, rivers, and lakes in a particular watershed. They are governed by the topography of the land, whether a particular region is dominated by hard or soft rocks, and the gradient of the land. A drainage system (agriculture) is an intervention to control waterlogging aiming at soil improvement for agricultural production A drainage system (industrial and residential) is a facility to dispose of liquid waste.
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The arrangement in which a stream erodes the channels of its network of tributaries.