How does a stream valley form and deep will it be down cut?

A stream valley forms through the process of erosion, where flowing water carves out the landscape, creating a channel and shaping the surrounding terrain. The depth of downcutting depends on factors such as the stream's velocity, sediment load, and the geology of the area; streams in soft rock may create deeper valleys than those in harder rock. Over time, the valley may widen and evolve through various processes, including lateral erosion and sediment deposition. Ultimately, the depth and profile of a stream valley can vary significantly based on these environmental factors.