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<br />Table 2. Peak Flow Estimates for Existing Regulated Conditions on Major Tributary Streams, Green River Basin.
<br />DRAF17 February25, 1998
<br /> Y River L. Snake River Duchesne River Wbite River Price River San Rafael River
<br />Recurrence
<br />Interval, Years Peak Flow
<br />R'/s Peak Flow
<br />tt'/s Peak Flow
<br />Fels Peak Flow
<br />fl'/s Peak Flow
<br />ft'/s Peak Flow
<br />R'/s
<br />2 10,100 4,900 3,800 3,900 4,100 1,600
<br />5 13,000 7,300 6,600 5,400 6,900 2,400
<br />10 14,800 8,900 8,200 6,400 8,700 3,000
<br />25 16,900 11,100 10,100 7,600 10,800 3,700
<br />50 18,400 12,700 11,300 8,400 12,200 4,200
<br />100 19,900 14,500 12,300 9,200 13,500 4,800
<br />
<br />0 Channel Hydraulics
<br />Flow Routing
<br />The results available for monitoring of the Green River during the runoff season in 1996 indicate
<br />several key findings regarding flow routing. First, for flows in the range of 12,000 ft3/s to 18,000
<br />ft3/s, the travel time from Jensen to Stillwater Canyon is approximately 85 hours and the mean
<br />velocity is about 1.1 m/s. Secondly, for flows from 5,000 ft3/s to 12,000 ft3/s, the travel time
<br />between the same two points is approximately 100 hours with a mean velocity of 0.9 m/s. Third,
<br />downstream from Jensen, the Green River is a gaining river, that is, average discharge increases
<br />with distance downstream from Jensen. Fourth, the sharp peak discharge at Jensen flattens and
<br />increases in duration with the inflows from the White and Duchesne Rivers (FLO Engineering,
<br />Inc., 1997a).
<br />Floodplain Inundation
<br />The occurrence and properties of flooded bottomlands are largely a function of discharge
<br />magnitude and channel morphology. The interaction between the river and the bottomlands can
<br />be affected by presence of levees or other barriers. The duration of flooding is the period during
<br />which a flooded bottomland area maintains connectivity with the river. Ponded water remaining
<br />in depressions after the recession of the flood is not considered in the flood duration analysis nor
<br />is water ponded by seepage. Sedimentation and erosion processes in the channel can affect the
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