The goal of the high-flow experiment, the third since 1996, is to see if such high flows can help reconstruct some of the canyon’s beaches and sand bars that are instrumental to ecological systems and native fishes that have suffered since the building of the Glen Canyon Dam in 1963.
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By allowing flow of water that, at its peak, will be more than three times its normal rate (to a volume of 41,500 cubic feet per second), researchers hope to flush some of the dam system of its backed-up sediment and reconstruct habitat downstream. It is expected that the high water-flows will rebuild eroded beaches downstream of the dam by moving sand accumulated in the riverbed onto sandbars.

That in turn will allow the re-establishment of eddy sandbars that provide the slow moving, backwater channels vital for native fish species. The sand bars also provide camping areas for river runners and hikers, and the beaches provide sand to the canyon that helps preserve archaeological resources.