COLORADO RIVER HIGH FLOW EXPERIMENT
Recent high flows on the Paria River and other Colorado River tributaries have provided an opportunity to test new techniques for managing the Lower Colorado River ecosystem. These recent flows have deposited large amounts of sediment in the main channel of the Colorado River. This high flow experiment, which is a controlled release from Glen Canyon Dam, is intended to move the sediment from the bottom of the main channel and rebuild sandbars, beaches, and backwater areas in the Grand Canyon. Since the closure of Glen Canyon Dam, sandbars have been eroded as a result of reduced sediment load in the river. Sandbars, beaches, and backwater areas are important parts of the Grand Canyon ecosystem and are important for wildlife and recreational use.
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EXPLANATION 0 1/2 MILE Real-time data of Paria River discharge retrieved from the 09382000 U.S.G.S. STREAMFLOW-GAGING U.S. Geological Survey Web homepage STATION AND NUMBER 0 1/2 KILOMETER
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Pre flood Sand on channel bed
Cross sections illustrating the process of sediment mobilization and redeposition for the controlled flood Controlled Sand release of 1996 from Glen suspended flood Canyon Dam
Sand bars Post flood deposited on Sediment sampling on the Colorado Sediment sampling on the river banks River above Diamond Creek Paria River at Lees Ferry