The U.S. Department of Energy operates four regional power marketing administrations (PMAs) -- the Bonneville Power Administration (BPA), the Southeastern Power Administration (SEPA), the Southwestern Power Administration (SWPA), and the Western Area Power Administration (WAPA). These agencies all operate on the principle of selling wholesale electric power with preference given to publicly or cooperatively owned utilities "at the lowest possible rates to consumers consistent with sound business practices" under the Flood Control Act of 1944 (16 U.S.C. ?825s). Maintaining competitive rates sufficient to cover operating costs and repay the federal investment in the hydropower dams and transmission systems amid drought, legal challenges, and customer pressure for cost reductions are some of the challenges faced by these agencies, and issues tied to these challenges may come before Congress.