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0 0 <br />year. <br />D. An ongoing suspended- sediment load measuring program will be re- established at <br />the Green River, Utah, gage on the Green River. This program will consist of 120 <br />observer (box) suspended sediment and 9 total cross - section samples per year. <br />Ninety (90) of the box samples and all 9 of the cross- section samples will be <br />analyzed to determine the sand /silt fraction and 30 of the box samples will be <br />analyzed for concentration only. The cross- section samples will be collected for <br />purposes of developing a coefficient to relate the box samples to the total suspended <br />sediment load in the river. <br />E. A 1 -year program of sediment -load measurements, including both suspended- and <br />bed -load, and bed - material sampling will be conducted at an appropriate site near the <br />head of Lodore Canyon on the Green River. <br />F. A 1 -year sediment monitoring program will be conducted near the confluence of the <br />Green and Yampa Rivers to establish the relationship between sediment load and <br />discharge in the two rivers, and to define the sediment load discharge from Lodore <br />Canyon during high flows. Three sampling sites will be established for this task: <br />lower Yampa River just upstream from Echo Park, Green River just upstream from <br />c(j the Yampa River confluence, and Green River in Echo Park downstream from the <br />confluence. The following data will be collected at each location (minimum 10 sets <br />per year): <br />• Sediment load measurements, including suspended sediment and bed load <br />• Bed material samples <br />• Discharge measurements <br />• One cross - section survey <br />G. A channel- monitoring program will be established to document the morphological <br />response of the river to high flows in the Green River, particularly as they are affected <br />by future jet tube releases from Flaming Gorge Dam. Four reaches have been <br />identified for this program: <br />• Rainbow- Island Park reach (6 to 10 cross sections) <br />• Razorback sucker spawning bar and Escalante reach (6 cross sections) <br />• Ouray Wildlife Refuge reach (6 to 10 cross sections) <br />• Canyonlands reach (2 or 3 cross sections) <br />New cross sections will be established and monumented at the Rainbow - Island Park <br />reach, and existing cross sections would be utilized at the remaining reaches. To <br />identify the changes that result from the high -flow runoff, cross sections should be <br />surveyed at each reach at least 3 times during the year, with the first survey prior to <br />the peak discharge (probably early April), the second survey at or near the peak (late <br />May), and the third after passage of the snowmelt hydrograph (August or <br />September). All 4 sites will be surveyed during the initial year of the program to <br />establish the baseline condition. The Razorback spawning bar and Rainbow- Island <br />5 <br />