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<br />I
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<br />NAU Sand Bar Swdies
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<br />Final Report
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<br />Table 1, Summary of sand volume changes in the 3-km study reach.
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<br /> Segment 1 Segment 2 Segment 3 Segment 4
<br />Survey
<br />Date Meln Eddy 1 Eddy 2 Main Eddy 3
<br /> Channel Channel
<br />August 10 Paria River Flood
<br />970815 24.340 23.140 7.950 26,300 8,870 2.510 .350
<br />September 7, 15, and 26 Paria River Floods
<br />970927 84.090 38.620 13.030 65.040 31,280 66,850 10.850
<br />Net Deposition from 1997 Paria River Floods
<br /> 108,430 61.760 20,980 91,340 40.150 69,360 8,940
<br />Pre 1997 Test Row
<br />971103 -18,870 -31,050 .6.270
<br />Day 1
<br />971104 a.m, -14,760 2,000 -3,860
<br />971104 p.m, 740 560
<br />Day 2
<br />971105 a.m. 280 -12,790 -1,800
<br />971105 p,m, 1,140 1230
<br />Post 1997 Test Flow
<br />971106 -1,760 -130 1.300
<br />Net Pr... to POSl1997 Test Row Erosion
<br /> -16,240 -9,040 -2,570
<br /> Values are in un~s of cubic meters
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<br />using the methods described above for the study reach downstream from the Paria River, Each study
<br />site is located at a fan-eddy complex, To reduce the influence of the Little Colorado River, only 12 of
<br />the 35 sites were included in the present analysis [study site locations, descriptions, and patterns of
<br />erosion and deposition between 1991 and 1997, at all 35 sites is provided by Kaplinski et ai, (1995;
<br />1998) and Hazel et ai, (1999)]. Volume data from three environments in the fan-eddy complex (main
<br />channel, eddy, and high-elevation sand bar) were converted to average thickness, respectively, to
<br />provide an unambiguous means of reporting change between surveys, We define the high elevation
<br />sand bar as bedfonns deposited in eddies occuning above the 566 m3/s (20,000 fe Is) stage elevation,
<br />Distances along the Colorado River in Grand Canyon are traditionally measured in river miles, with
<br />river mile 0 beginning at Lees Ferry, Arizona, Accordingly, study site reference numbers use river
<br />mile location (Fig, I),
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