The Buchanan Dam is a multiple arch dam located on the Colorado River of Texas. The dam forms Lake Buchanan and was the first dam to be completed in the chain of Texas Highland Lakes. The dam is used for generating hydroelectric power and for flood control and is located about 12 miles (19 km) west of Burnet, Texas.

An arch dam is a concrete dam that is curved upstream in plan. The arch dam is designed so that the force of the water against it, known as hydrostatic pressure, presses against the arch, causing the arch to straighten slightly and strengthening the structure as it pushes into its foundation or abutments. An arch dam is most suitable for narrow canyons or gorges with steep walls of stable rock to support the structure and stresses. Since they are thinner than any other dam type, they require much less construction material, making them economical and practical in remote areas.