GCDAMP Sediment

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Erosion of sandbars (beaches) along the Colorado River in Grand Canyon was first reported in the early 1970s, approximately 10 years after completion of Glen Canyon Dam. Since then, scientific studies have been conducted to monitor changes in sandbars and changes in the amount of sand stored on the bed of the river. One of the outcomes of these studies has been the implementation of flow experiments intended to rebuild eroded sandbars, especially by the release of controlled floods, also called “high-flow experiments,” from Glen Canyon Dam. The sediment and geomorphology projects at Grand Canyon Monitoring and Research Center include the collection and processing of data to provide information needed to conduct controlled floods and to evaluate the outcome of each controlled flood and the long-term effects of controlled floods and normal dam operations on sediment-related resources. Desired Future Condition: High elevation open riparian sediment deposits along the Colorado River in sufficient volume, area, and distribution so as to provide habitat to sustain native biota and desired ecosystem processes • Nearshore habitats for native fish • Marsh and riparian habitat for fish (food chain maintenance) • Cultural resource preservation • Maintenance of camping beaches

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Updates

Links The HFE Page Sediment Gages Colorado River at Lees Ferry Paria River at Lees Ferry Colorado River at 30 mile Colorado River above LCR Bright Angel Creek Shinumo Creek Colorado River abv Lava Canyon rm66 Colorado River bl rm127 Kanab Creek Havasu Creek Colorado River abv National Canyon Colorado River bl Diamond Creek Colorado River abv Spencer rm246 Presentations and Papers 2016 Conditions and processes affecting sand resources at archeological sites in the Colorado River corridor below Glen Canyon Dam, Arizona Long-term continuous acoustical suspended-sediment measurements in rivers - Theory, application, bias, and error Project 2: Streamflow, Water Quality, Sediment Transport, and Sand Budgets in the Colorado River Ecosystem Sandbars and Sediment Storage in Marble and Grand Canyons: Response to Recent high-flow Experiments and Long-Term Trends Observations of sand dune migration on the Colorado River in Grand Canyon using high-resolution multibeam bathymetry 2015 Updates on 2014 HFE, Paria sediment inputs, and sediment mass balance Alvarez, L.V. (2015) Turbulence, Sediment Transport, Erosion, and Sandbar Beach Failure Processes in Grand Canyon. Ph.D. Dissertation, Arizona State University, Tempe, AZ, 176pp. Grams, P. E., J. C. Schmidt, S. A. Wright, D. J. Topping, T. S. Melis, and D. M. Rubin (2015), Building Sandbars in the Grand Canyon, EOS, Trans. Am. Geophys. Union, 96(11), 12–16. Streamflow, Water Quality, and Sediment Transport in the Colorado River Ecosystem Sandbars and Sediment Storage in Marble and Grand Canyons: Response to Recent High-flow Experiments and Long-term Trends Other Stuff Eddies occur adjacent to rapids and the flow in the eddy is related to the flow characteristics in the rapid. Sand bars were typically larger before the dam.(Science Background for HFE Planning- Jack Schmidt, GCMRC_KA 2013) Sediment Presentation- AMWG Jan 2002 Sediment White Paper- AMWG Jan 2002 The United States Geological Survey estimates that the Colorado River below Glen Canyon Dam only has 6 percent of the sediment that it received before the Glen Canyon Dam was built in the 1960s.