As one of the four power marketing administrations within the U.S. Department of Energy, the Western Area Power Administration (WAPA)'s role is to market wholesale hydropower generated at 57 hydroelectric federal dams operated by the Bureau of Reclamation, United States Army Corps of Engineers and the International Boundary and Water Commission. WAPA delivers this power through a more than 17,000-circuit-mile, high-voltage power transmission system to more than 700 preference power customers across the West. Those customers, in turn, provide retail electric service to more than 40 million consumers. WAPA is headquartered in the Denver, Colorado suburb of Lakewood, Colorado. WAPA’s service territory spans 15 central and western states, including Arizona, California, Colorado, Iowa, Kansas, Minnesota, Montana, Nebraska, Nevada, New Mexico, North Dakota, South Dakota, Texas, Utah, and Wyoming. History WAPA was created in Section 302 of the Department of Energy Organization Act signed into law by President Jimmy Carter, Aug. 4, 1977. Under the statute, WAPA assumed power marketing responsibilities and ownership, operation and maintenance of the federal transmission system from the Bureau of Reclamation. Reclamation retained responsibility for other uses of the multi-purpose water projects, including dam and powerplant construction, operation and maintenance. Power marketing WAPA's hydropower resources are produced at federal dams in 11 states, representing about 40 percent of hydroelectric generation in the western and central United States. WAPA also formerly marketed the United States’ 547-megawatt entitlement from the coal-fired Navajo Generating Station near Page, Arizona until its closure on 18 November 2019. Hydropower is considered a byproduct of the federal dams whose primary purpose is to store water for irrigation and to provide navigation and flood control. Before hydropower, multiple other uses were adopted for federal dams, including municipal and industrial water needs, recreation, salinity control and fish and wildlife. Initial powerplants at the dams were constructed to first serve project-use loads and then to provide revenue from power sales. WAPA first reserves power to meet project needs called project-use power; this energy powers the facilities at the dams and pumps water at Federal irrigation projects. WAPA then sells the surplus generation at cost-based rates to preference power customers under long-term contracts. Any remaining hydropower is then sold at market-based prices on the short-term spot market. Cost-based rates are designed to cover annual operations and maintenance and the federal investment in the facilities, plus interest. WAPA only charges market rates when selling surplus hydropower and transmission