Water is one of the most destructive agents in nature. It flows almost everywhere over the land surface, leaving its mark by eroding solids, dissolving minerals, and picking up debris.
This running water dissolves rock, picks up soil particles, and carries them downstream as suspended load.
It also washes away subsurface soils with tributary gullies or small channels. Running water leaves its mark on all terrain slopes through which it passes.
In humid regions, which receive heavy rainfall running water is considered the most important of the geomorphic agents in bringing about the degradation of the land surface. There are two components of running water.
- Overland flow on general land surface as a sheet
- linear flow as streams and rivers in valleys