HR: 1340h
AN: H53D-0495 [Abstracts]
TI: Investigating Effects of the November 2004 High-Flow Release From Glen Canyon Dam on Aeolian
Sand-Transport Rates in the Colorado River Corridor, Grand Canyon, Arizona
AU: * Draut, A E
EM: adraut@usgs.gov
AF: US Geological Survey / UC Santa Cruz, USGS Pacific Sciences Ctr
400 Natural Bridges Dr., Santa Cruz, CA 95060
United States
AU: Rubin, D M
EM: drubin@usgs.gov
AF: US Geological Survey, USGS Pacific Sciences Ctr
400 Natural Bridges Dr., Santa Cruz, CA 95060
United States
AB:
In November, 2004, a 60-hour experimental flood release from Glen Canyon Dam held the Colorado River flow through Grand
Canyon, Arizona, above 1,160 m3 s-1 (41,000 ft3 s-1). This high-flow experiment was designed to rebuild
fluvial sand deposits, restoring a component of the ecosystem that had declined since closure of the dam in 1963. Transport
and deposition of aeolian sand has important implications for archaeological resources in the river corridor, many of which
are located in and covered by aeolian deposits. This study presents aeolian sediment-transport data collected in the river
corridor during the year before and in the months after the flood experiment. At each of the six study locations, substantial
new deposition of fluvial sand occurred as a result of the 2004 flood, which temporarily increased the amount of sand
available for aeolian entrainment. However, high daily fluctuations (142 to 566 m3 s-1; 5,000 to 20,000 ft3
s-1) of the river flow from January to March 2005 removed much of the new sand before the start of the 2005 windy
season. The greatest potential for aeolian re-distribution of flood-deposited sand occurred during the April-May windy
season, during which the highest measured winds can locally exceed 25 m s-1, with sand-transport rates ~5 kg cm-1
day-1. These data may be used to guide decisions regarding future experimental floods and subsequent flow schedules, if
maximizing sand redistribution by wind is a management objective.
DE: 1824 Geomorphology: general (1625)
DE: 1895 Instruments and techniques: monitoring
DE: 4802 Anoxic environments (0404, 1803, 4834, 4902)
DE: 4902 Anthropogenic effects (1803, 4802)
SC: Hydrology [H]
MN: Fall Meeting 2005