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did not adequately account for the variance in sediment discharge and water discharge data. Since sediment transport equations based on measured sediment discharges have been derived for more types of sediment discharge than have equations based on estimates from the Modified Einstein procedure, subsequent analysis of sediment transport in the Deerlodge Park reach will utilize the measured sediment discharge versus water discharge relations and their corre- sponding annual sediment loads. The annual total sediment load of 2.04 million ton/yr based on 1982 and 1983 measurements agrees with Andrews' (1978, p. 11) estimate of annual total sediment load for Deerlodge Park of 2.0 million ton/yr. His estimate was based on suspended-sediment loads measured at station 09251000 Yampa River near Maybell and station 09260000 Little Snake River near Lily, bedload estimates computed with the Meyer-Peter and Mueller (1948) formula, and an adjustment for the intervening ungaged drainage area. The flow duration, sediment-transport-equation method of computing annual sediment loads (Miller, 1951) estimates the amount of annual sediment load transported by successive increments of water discharge, of a given duration. These incremental sediment loads are summed to give the long-term annual sediment load. Cumulative increments of total sediment load are potted against discharge in figure 7, and the relative portion of total annual sediment load transported by streamflow greater than a specified level is thus illustrated. Approximately one quarter of the annual total sediment load transported by the Yampa River through Deerlodge Park is carried by discharges greater than 12,000 ft3/s. On average, such flows are equaled or exceeded about 2.5 percent of the time (fig. 6), or about 9 days per year. ESTIMATED IMPACTS OF WRIER RESQURCE DEVELOPMENT Sediment loads computed for the Yampa River at Deerlodge Park are esti- mates of long-term, average sediment transport through this reach and into the Yampa Canyon. The annual sediment load and streamflow are influenced by geomorphic, hydrologic, and climatologic conditions prevailing today and in the recent past. The Yampa River appears to be in equilibrium through the Deerlodge Park reach. Transport of material through this reach is equal to the amount of material supplied to it, on an average basis. No physical evidence exists to suggest long-term aggradation or degradation in Deerlodge Park. The flood plain is broad and has no strath terraces to suggest recent progressive downcutting by the river. The river is not bordered by berms or other ~overbank deposits that would indicate progressive aggradation. Large cottonwood trees growing on the flood plain indicate that the level of the flood plain has been relatively constant for several decades. Also on the flood plain, near the U. S. Geological Survey gaging station, are adobe and sod buildings that date from about 1903 {Glade Ross, National Park Service, oral commun., 1983). Comparison of the pattern and position of the Yampa River from Lily Park to the canyon entrance, documented by survey in 1922 and by aerial photography in 1970, reveals no changes except those typical of rivers transporting large sand loads, such as bend migration and bar formation. 21