GCDAMP Sediment

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The Paria River flowing into the mainstem Colorado River

Sediment and Geomorphology 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, or HFEs,” 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 for Sediment-Related Resources 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 and Information The High Flow Experiment (HFE) Page Aeolian Sand Transport Page Near Shore Ecology (NSE) Study of the fall steady flow test The Low Steady Summer Flow Experiment (LSSF) Page Sediment Gages Paria River at Lees Ferry Colorado 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 Sand Mass Balance Reaches in Grand Canyon Upper Marble Canyon Lower Marble Canyon Eastern Grand Canyon East Central Grand Canyon West Central Grand Canyon Western Grand Canyon and the Lake Mead Delta Presentations and Papers 2017 https://www.usbr.gov/uc/rm/amp/twg/mtgs/17jan26/AR2_Dean.pdf Hydrologic Change and the Geomorphic Transformation of the Little Colorado River: Implications for Sediment Delivery to the Grand Canyon PPT] 2016 Voichick, N., Kennedy, T.A., Topping, D.J., Griffiths, R.E., and Fry, K.L., 2016, Water clarity of the Colorado River—Implications for food webs and fish communities: U.S. Geological Survey Fact Sheet 2016–3053, 4 p. Sandbar Modeling Project Update Status of Sediment Resources – August 2016 Grand Canyon Monitoring and Research Center Science Updates and PPT (BO Compliance, Trout Updates, Green Sunfish, Fisheries PEP, Partners in Science) Topping, D.J., and Wright, S.A., 2016, Long-term continuous acoustical suspended-sediment measurements in rivers—Theory, application, bias, and error: U.S. Geological Survey Professional Paper 1823, 98 p., http://dx.doi.org/10.3133/pp1823. 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 GCMRC Science Update - Sediment GCMRC Science Update - Sediment 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. Glen Canyon Tailwater Fishery “Integrating Fish and Channel Mapping GCMRC’s Online Mapping and GIS Resources 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 Glen Canyon Tailwater Fishery “Integrating Fish and Channel Mapping GCMRC’s Online Mapping and GIS Resources 2014 Science Updates - Recent Research on Sand, Bugs, and Fish Measuring Bed Sediments to Improve Sediment Budgets and Physical Habitat Assessment Status of Sediment Resources Sandbars and Sand Storage in Marble and Grand Canyons (Grams) Processing fine sediment transport data: procedures, processing, and bottlenecks (Griffiths) 2013 GCMRC Update - Status of Resources and Sediment Conditions 2013 Overflight Wrapup GCMRC Science Update on Sediment and Fisheries 2011 GCMRC update on Chub, Temperature, and Sediment Other Stuff Measuring turbidity Question: What is the difference between the turbidity units NTU, FNU, FTU, and FAU? What is a JTU? Summary: Turbidity units NTU, FNU, FTU, FAU, and JTU Answer: NTU stands for Nephelometric Turbidity Unit and signifies that the instrument is measuring scattered light from the sample at a 90-degree angle from the incident light. FNU stands for Formazin Nephelometric Units and also signifies that the instrument is measuring scattered light from the sample at a 90-degree angle from the incident light. FNU is most often used when referencing the ISO 7027 (European) turbidity method. NTU is most often used when referencing the USEPA Method 180.1 or Standard Methods For the Examination of Water and Wastewater. When formazin was initially adopted as the primary reference standard for turbidity, units of FTU or Formazin Turbidity Units were used. These units, however, do not specify how the instrument measures the sample. FAU or Formazin Attenuation Units signify that the instrument is measuring the decrease in transmitted light through the sample at an angle of 180 degrees to the incident light. This type of measurement is often made in a spectrophotometer or colorimeter and is not considered a valid turbidity measurement by most regulatory agencies. A JTU or Jackson Turbidity Unit is a historical unit used when measurements were made visually using a Jackson Candle Turbidimeter. Water was poured into a tube until a flame underneath the tube could no longer be distinguished. The turbidity units NTU, FNU, FTU, AND FAU are all based on calibrations using the same formazin primary standards. Therefore when a formazin standard is measured, the value for each of these units will be the same, however the value on samples may differ significantly. 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. Flash Flood videos Paria River Flash Flood 8/3/16 Buckskin Gulch Flash Flood 8/4/16 Buckskin Wash Flash Flood / Debris Flow 2013 Paria River Flash Flood / Debris Flow 8/19/12 Glen Canyon and Page Arizona Flooding May 22 2009