A waterfall is an example of a landform shaped by the geomorphic process of river erosion. Perhaps the most famous example of a waterfall are the falls at Niagara Falls.

A very steep or vertical slope will be found at a typical waterfall. Flowing water will generall fall with great force and energy. A waterfall will form in the upper course of a river valley. This is likely to be an upland or mountain area. Downward flow of water results in deepening of the river bed, which is called vertical erosion.

Waterfalls are most likely to form where the channel slope becomes steeper or is composed of varying bands of soft and hard rock. Erosion is most likely to occur when the volume or speed of the flow of water increased. Weak points in the bedrock will be attacked by hydraulic action, which is the force of fast flowing water. Abrasion, which is the process of the river’s load eroding the soft bedrock, will loosen the bedrock. This makes the river bed more vulvnerable to hydraulic action. These processes will cause the water to fall from a higher level to a lower level. This is a waterfall.

Vertical erosion will continue at the foot of the waterfall, leading to the formation of a plunge pool. Swirling turbulence in the plunge pool will lead to undercutting at the base of the waterfall.

Waterfall formation is a sign of a graded profile of a river. Erosion at the front of the waterfall is called headward erosion. This causes a constant repetition of undercutting and collapse. The front of the waterfall will retreat upstream over time. This may increase the height of the waterfall.