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3.5 are filled with coarse sand. Through most of its length to the town of Basalt, the channel capacity is adequate to contain the predam mean annual flood of approximately 1,000 cfs. Some flooding did occur into low-lying areas of the flood plain at these flow rates prior to construction of Ruedi Dam. The channel did not experience any significant bank or bed erosion. from predam, mean annual floods. Sources of sediment to the Fryingpan River below Ruedi Dam are from Rocky Fork Creek and numerous small tributaries. Rocky Fork Creek is the only tribu- tary with a sustained discharge over the year. During the spring runoff, Rocky Fork yields fine sediments that produce turbidity. Other small tributaries produce brief periods of turbidity in the Fryingpan River. Under present operating conditions for Ruedi Reservoir, streamflows in the Fryingpan River have been altered compared to those of the natural watershed. Flows in the winter months of November through February currently average 164 cfs while unregulated winter flows would average 43.3 cfs. Mean monthly flows in June currently average 109 cfs while unregulated flows would average 1,091 cfs. The present operation of the Ruedi Reservoir thus reduces peak summer flows in the Fryingpan River below Ruedi Reservoir and augments winter flows. Table 3.2 gives measured mean monthly flows in the Fryingpan River for the average, dry, and wet years of record (period of record from 1948 to 1983). The average annual undepleted water yield from the Fryingpan watershed is 166,500 AF. Average depletions by diversions in the headwaters of the watershed are 60,100 AF (53,600 AF for Fryi ngpan -Arkansas Project and 6,500 AF for Busk-Ivanhoe). Average depleted inflow to Ruedi Reservoir is 106,400 AF, which is slightly in excess of the reservoir capacity of 102,400 AF. The Roaring Fork above its confluence with the Fryingpan is unregulated. This upper portion of the Roaring Fork watershed produces some 45 percent of the water yield from the entire Roaring Fork watershed. Remaining water yield comes primarily from the Fryingpan River (19 percent) and the Crystal River (32 percent). The Roaring Fork River below the Fryingpan confluence extends 27 miles from Basalt to Glenwood Springs with an average gradient of 27 feet per mile. The river has a boulder- and cobble-bed channel which is well incised into the alluvial valley deposits along most of its length. The channel has adequate capacity for the mean annual flood except in some low-lying flood plain areas. The streamflows in the Roaring Fork River are typial of the natural runoff cycle of high mountain watersheds. Table 3.3 gives measured average monthly