dam

A dam is a large structure which blocks the flow of water in a channel. Dams are frequently used to generate hydroelectric power, or they can be built simply to divert water from one course to another or to create an artificial lake.

The barrier changes the flow or retention of water in the channel. Power generation, diversion, and impoundment are different purposes served by that obstruction.

Dam forms differ in their construction and resistance to water pressure. An arch dam uses a curved form, while a gravity dam relies primarily on its mass.