The Interior department will begin a five-day "high-flow experimental release" at Glen Canyon Dam at noon Nov. 19.
The release is part of a long-term protocol announced in May by Interior Secretary Ken Salazar to meet water and power needs and resolve problems with downstream sediment and non-native fish predation on the Colorado River below the dam.
Scientists have determined the correct conditions exist to conduct a high-flow release to benefit downstream resources, including camping beaches, sandbars, backwater habitats, riparian vegetation and archeological sites.
The total maximum release from the dam will reach approximately 42,300 cubic feet per second 27,300 cfs of full-capacity powerplant releases and a bypass release through four river outlet tubes sending 15,000 cfs of water out over the Colorado River in what authorities say will be a spectacular visual display.
The total duration of the high-flow release will be nearly five days, according to an Interior news release.
Lisa Iams of the Bureau of Reclamation said the release is projected to drop the water level in Lake Powell by 2 feet, but an adjusment in later releases will ultimately not alter what the lake's level would have been anyway.
The Salt Lake Tribune