The energy of river is dependent on the velocity of its flow and its volume of water. The energy of the river is used to overcome friction in the riverbed and also to erode and transport material. It is responsible for the processes and landform that takes place on the river.
Factors affecting Volume and Velocity includes size of the drainage basin, vegetation cover, Climate, permeability of rock, amount of discharge, gradient of the land, shape of channel cross-section and the roughness.