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i <br />5) In the Yampa Canyon, extensive net degradation of long reaches of the <br />channel that often accompanies a sediment budget deficit probably will not <br />occur because the channel flows on bedrock, talus, and coarse debris from <br />tributaries. If the sediment load is drastically reduced, local erosion of <br />sand from some beaches, bars and pools may occur (Elliott,1984). <br />Whenever the running balance is negative, the balance is set equal to zero, <br />instead of being allowed to accumulate negatively. This is done to account <br />for armouring of the channel, since the reach is non-alluvial, armoured and <br />a deficit indicates only a potential to scour. The number of times when <br />the running balance was set to zero in each water year is also recorded. <br />6) Discharge is con-currently summed on a daily basis, and reported as monthly <br />and annual means for the same period. <br />7) For each program run, the following tables are constructed: <br />a) Discharge at Deerlodge Park (equivalent to Mathers Hole) <br />b) Monthly and annual sediment transport in tons at Deerlodge Park. <br />c) Monthly and annual sediment transport in tons at Mathers Hole. <br />d) Monthly and annual running balance of sediment within the Deerlodge <br /> Park - Mathe rs Hole reach. <br />8) Program runs were preformed using the 'historic' record at Deerlodge Park, <br />in addition to a baseline condition and a 'with project' condition. The <br />'with project' flows are from a study prepared for the Nature Conservancy <br />by W. W. Wheeler & Associates, Inc., which estimated the mean monthly flow <br />at the Yampa River near Maybell station due to operation of the senior <br />Juniper Project water rights. <br />This project was selected as being representative of a worst case scenario, <br />because it would regulate flows for power generation while trapping <br />relatively small percentages of the Yampa's sediment load and con-currently <br />not reducing sediment delivery from the Little Snake River. Regulation of <br />flows for power generation changes the distribution of flows, reducing the <br />peaks which transport the majority of sediment load, and increasing the <br />baseflow months. Adjustment of the 'historic' daily flow record using the <br />baseline and with project monthly means is detailed later. <br />9) The program allows each daily flow in the peak flow months of Apri-1, May, <br />and June to be decreased by a percentage. Separate percentages may be <br />specified for each month. The sum of the reduced flow is then <br />redistributed evenly into the peak power generation months of July - <br />September and December - March.