An arch dam is a type of dam that is curved and designed to direct water pressure against its walls. This shape allows the dam to efficiently transfer the force of the water to the canyon walls, making it suitable for locations with strong rock formations. Arch dams are typically made of concrete and can be built in narrow, steep valleys. These structures are often used for hydroelectric power generation, water supply, and flood control. Famous examples of arch dams include the Hoover Dam and the Glen Canyon Dam, both of which play significant roles in managing water resources in the United States.