Hydroelectric Dams

Pursuant to a congressional request, GAO reviewed the effects of the Elwha and Glines Canyon dams on fisheries in the Elwha River in Washington, focusing on the: (1) Federal Energy Regulatory Commission's (FERC) authority to license those dams; (2) potential costs of removing the dams to restore the fisheries; (3) potential costs of restoring the fisheries without removing the dams; and (4) effectiveness of both dam removal and dam retention coupled with mitigation measures in restoring fish to the Elwha River.

GAO found that: (1) FERC estimated that the cost of removing both dams would be about $61 million, and was subject to an increase of $124.6 million if FERC requires the transfer of dam sediment to a disposal site; (2) FERC estimated that the cost of constructing fish passage facilities with the dams in place ranged from $20 million to $40.4 million, depending on the facilities selected; (3) FERC estimated the annual cost of operating and maintaining such facilities at $160,000 to $260,000; (4) FERC estimated that it would cost $3.1 million to construct hatchery facilities to restore fish upriver from the dams with passage facilities, and would cost $240,000 a year to operate; (5) FERC believed that dam removal would provide the best prospects for restoring the fisheries, but would also result in the loss of nearly 40 percent of local power supplied by the dams hydroelectric generators; (6) FERC could purchase replacement power from a local utility; and (7) although dam retention with mitigation measures would allow the continued use of dam produced power to meet part of its energy requirements, the FERC analysis indicated that such measures would increase dam-generated electricity costs to about the local utility's rate.