 Electricity from the dam 's powerhouse was originally sold pursuant to a fifty @-@ year contract , authorized by Congress in 1934 , which ran from 1937 to 1987 . In 1984 , Congress passed a new statute which set power <unk> from the dam from 1987 to 2017 . The powerhouse was run under the original authorization by the Los Angeles Department of Water and Power and Southern California Edison ; in 1987 , the Bureau of Reclamation assumed control . In 2011 , Congress enacted legislation extending the current contracts until <unk> , after setting aside 5 % of Hoover Dam 's power for sale to Native American tribes , electric <unk> , and other entities . The new arrangement will begin in 2017 . The Bureau of Reclamation reports that the energy generated is allocated as follows : 
