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We analyzed the bed's response to changes in discharge, and we attempted to determine . the discharge which caused scour and fill of the bed. Depth is only recorded during direct discharge measurements, and the resolution of bed elevation data is relatively low (approximately 2 per month) compared with the published daily measurements determined from the stage elevation. Because of this low resolution, it was not possible to determine precisely at what discharge the bed began to scour in each year directly from the records. However, a decrease in thalweg elevation between two discharge measurements indicates that at some time between the measurements the discharge was sufficient to scour the bed. Mean daily discharges between measurements where the bed elevation changed more than 0.25 m were determined and compared with discharges during periods where bed elevation remained constant. We used a two-tailed t-test and assumed equal variance to determine if the maximum discharges during periods of scour , were drawn from statistically different populations than the maximum discharges when the bed elevation remained constant. We also created histograms of the mean daily discharges for periods of bed stability and periods of scour to facilitate comparisons. We also used the discharge records to look for long term changes in channel width. The distance between right and left edge of water is recorded at the time of each discharge measurement. This measurement represents the top width of the inundated portion of the' channel at the given discharge, but does not define the boundaries of the channel. To determine if the width of the channel has changed, we analyzed discharge measurements made between 10% greater than and 25% less than what we earlier had determined to be the bankfull discharge of 105 m3/s (3700 Wls). Because the location of discharge measurements varied, we limited the analysis to measurements made within a 15