Question

Explain why river mouth have to be periodically dredged to keep it navigable

Answer 1

as river carries a lot of sediments which settle at estauries, so it's dredged to keep it navigable

plz mark as brainly
regards

Answer 2

Dredging is the process in which a machine is used to extract the material from the water to relocate or put it somewhere else.

This is mainly followed because the river is full of sediments that are used for the construction purpose.

Also, they help in extracting some of the valuable material that can be sold in the market to increase revenue.