Giant steel tubes began funneling water into the Grand Canyon on Wednesday. The three-day, man-made flood is supposed to help restore the canyon’s ecosystem, which was changed after the Glen Canyon Dam was built in 1983.
Four species of fish have become extinct and two others have become endangered since the dam’s construction. Officials hope the flood will redistribute sediment throughout the Canyon. This week will see four to five times the normal amount of water released from the dam.