The dam is practically invisible in this shot of the reservoir. The huge dam is the largest electric power-producing facility in the United States and one of the largest concrete structures in the world. The reservoir is called Franklin Delano Roosevelt Lake, named after the United States President who presided over the authorization and completion of the dam. Creation of the reservoir forced the relocation of over 3,000 people, including Native Americans whose ancestral lands were partially flooded. The dam has also blocked the migration of salmon and other fish upstream to spawn.