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<br />mean slope was 0.2% for the Clifton study site, 0,15% for the Com Lake site so the average
<br />was 0,175%, Pitlick et al (1999) reported that the 15-Mile Reach of the Colorado River had
<br />a mean bankfull width of 134 m and a mean slope 0,175%,
<br />
<br />The Yampa River had higher wetted width at non-runoff flows than the larger
<br />Colorado River. At a flow 01'600 cfs wetted width was 68 m at the Duffy Tunnel site, 60 m
<br />at Sevens, and 57 m at Lily Park (Table I). Mean slope was 0.06% for the study site at
<br />Duffy, 0.05% at Sevens, and 0,2% at Lily Park. Measurements obtained during the river
<br />channel survey of bankfull indicators produced a mean channel width of 85 m at Lily Park
<br />and 94 m at Sevens.
<br />
<br />Pitlick et al. (1999) reported a mean bankfull width 01'73.4 m for the Gunnison River
<br />from its confluence with the Colorado River (RM 0) to Delta (RM 57) and a mean slope of
<br />0,12%, Pitlicks' measurements indicated the Gunnison channel was about 53% the size of
<br />the Colorado River and about 74% of the Yampa River at Sevens. Since the Gunnison River
<br />did not have a 2-D modeled site, the wetted width at 600 cfs was not available, Mean
<br />bankfull width for the Delta study area was about 73 m and the slope is 0,19% (Pitlick et al.
<br />1999). Mean bankfull width at Escalante was about 68 m with a slope is 0.12% (Pitlick et al.
<br />1999), Channel geometry data was not available for the Gunnison River in the Austin reach,
<br />but it appeared in the field that Austin had the highest slope of the three Gunnison sites.
<br />
<br />Table I, Physical attributes ofYampa and Colorado River study sites (mean velocity, length,
<br />mean width, surface area at example modeled flows) from Anderson and Stewart 2003,
<br />
<br /> Big Gyp Clifton Corn lake Duffy Lilly Sevens
<br />'Mean Velocity (mis) 0,28 0,44 0,54 0,39 0,51 0,38
<br />Length (km) 3,3 4,2 3,9 2,1 3,1 2,9
<br />'Width (m) 22 59 50 68 57 60
<br />Percent Slope 0,15% 0.20% 0,16% 0,06% 0,20% 0,05%
<br />Flow (cis) Area (ha)
<br />40 6.7 12,9 11,8
<br />100 7,1 16,4 11.2 11,6 13,1 14.3
<br />200 7,6 19.6 16,3 12,6 14,9 15,6
<br />400 8.0 22,4 18,5 13,6 16,7 16.7
<br />600 24.2 19.8 14,2 17,6 17.4
<br />800 26.0 20,7 18,0
<br />1000 27.4 20,7
<br />1200 28,5 22,1
<br />1800 31.0 23,8
<br />
<br />Velocities and mean WIdth calculated a1600cfs. except for Big Gypsum calculated at IOOcfs
<br />
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