http://videos.oregonlive.com/oregonian/2011/06/round_butte_dam_fish_passage.html

It took nearly 15 years for Portland General Electric bring the selective water withdrawal system from design to it's operational state on Lake Billy Chinook, a reservoir near Madras. At 273 feet tall, most of the 1.3 million pound steel structure is submerged underwater. Acting as a fish catcher, the system restores downstream passage of Chinook, steelhead, and sockeye smelt. The fish travel through a series of pipes and ramps and are automatically sorted by size. They are then checked by hand, some are tagged and chipped. The fish are then carried by truck in a large container and brought downstream past the dam. Multiple water intake heights allow operators to control the temperature of water held back by the Round Butte Dam to match historic values. The system also generates power, making it one of a kind.