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L ~ ~ ~ Data from the platt maps and aerial photos provide excellent spatial coverage of the study reach, but these data provide poor resolution concerning when change occurred within the intervening 100 years. Discharge measurement notes of the gaging stations were analyzed to determine the detailed tempo-a! sequence of channel change at each gaging location. These archived records represent continuous physical measurements of the Duchesne River at two specific sties between 1910 and the present at Myton and 1942 and the present near Randlett. At each gage, cableway measurements were analyzed because they have been made at the same location. Many low-flow measurements were not analyzed because waded cross-sections were not made at the same location. Measurements made under ice were also excluded because the ice affects the depth, width, and velocity of the stream. Comparisons at Myton are very accurate because the cableway extends from a bridge abutment on river left and has not changed since 1911. Comparisons near Randlett are less accurate because the cableway was destroyed during the floods of 1983 and has not been replaced. High flow measurements are now taken from a bridge located 4.8 km upstream. Measurements since 1983 were not analyzed. From these records, the width, area, velocity, gage height, and maximum depth at each discharge measurement were recorded in a spreadsheet. Adjustments to the gage height were made to allow for datum shifts through time, and all data were adjusted to a common datum. Mean depth was calculated by dividing the cross-sectional area by the cross-sectiona! width. The mean streambed elevation was calculated by subtracting the mean depth of flow from the water surface elevation, recorded as the gage height. The elevation of the thalweg was calculated by subtracting the maximum depth from the gage height. Elevation of the thalweg and the elevation of mean depth were analyzed using only 22