A plunge pool develops at the base of a waterfall due to the force of the falling water eroding and undercutting the rock and sediment below. As the water cascades over the edge of the waterfall, it creates a powerful force that erodes the rock and sediment beneath it. Over time, this erosion deepens the pool and creates a basin-like depression at the base of the waterfall. This process is further exacerbated by the turbulence and churning of the water as it falls, which can also help to deepen and widen the plunge pool. As a result, the plunge pool becomes a natural feature that is characteristic of many waterfalls.
