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<br />response to the changed hydrology and sediment loads of the Green. This
<br />response cannot be adequately described by simple regime relationships
<br />relating channel dimensions and discharge.
<br />A modeling study of a short reach of the Green near river mile 255 involving a
<br />flow- and sediment-routing model indicated that bed topography in this reach
<br />adjusts rapidly to changes in discharge. A review of historical aerial pho-
<br />tography indicates that channel conditions in this reach have been relatively
<br />unchanged during the post-regulation period.
<br />The Green River channel has adjusted to the changed sediment regime wrought by
<br />the closure of Flaming Gorge. The potential for future channel changes
<br />exists, as evidenced by the response of the channel (i e., channel widening)
<br />to the increased flows of the early 1980's. At the present time, the channel
<br />configuration of the Green appears to be adjusted to the sediment supply,
<br />transporting t load with no net aggradation or degradation
<br />in a ong term. uture channel changes should be limited to ad'ust ents in
<br />channel characterisitics caused by changes in discha a 'ment
<br />and ranspor in a asin.
<br />Reoperation scenarios for Flaming Gorge Dam, if proposed, can be assessed
<br />using the suspended sand-load rating curves developed for the study reach. An
<br />imbalance or large changes in mean annual suspended sand load or effective
<br />discharge could be indicative of channel changes that would likely occur under
<br />the proposed operations.
<br />BIBLIOGRAPHY
<br />[1] Iorns, W. Y., C. H. Hembree, and G. L. Oakland, "Water Resources of the
<br />Upper Colorado River Basin - Technical Report," Geological Survey
<br />Professional Paper 441-A, 370 pp., GPO, Washington, DC, 1965.
<br />[2] Williams, G. P., and M. G. Wolman, "Downstream Effects of Dams on
<br />Alluvial Rivers," Geological Survey Professional Paper 1286, 83 pp., GPO,
<br />Washington, DC, 1984.
<br />[3] Andrews, E. D., "Downstream Effects of Flaming Gorge Reservoir on the
<br />Green River, Colorado and Utah," Geological Society of America Bulletin,
<br />pp. 1012-1023, vol. 97, 1986.
<br />[4] Pucherelli, M. J., Memorandum to Head, Remote Sensing Section entitled
<br />"Green River Channel Mapping Study." 5 pages plus bibliography, figures,
<br />and tables, Bureau of Reclamation Denver, CO, November 16, 1987.
<br />[5] Pucherelli, M. J., Memorandum to Head, Remote Sensing Section entitled
<br />"Green River Channel Morphology Study Using Four Dates of Aerial
<br />Photography, Near Green River, Utah." 4 pages plus bibliography,
<br />Bureau of Reclamation Denver, CO, August 31, 1988.
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