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<br />measurements and rarely deviated more than a few centimeters. Coordinate data from <br /> <br />the total station was reduced to distance and elevations relative to endpoints for purposes <br /> <br />of plotting. Bathymetric traces of the bed were analyzed in the lab. Average depths <br /> <br />below the water surface from the 4 repeated bathymetric surveys were converted to bed <br /> <br />elevations by subtracting the depth of water from the surveyed elevation of the water's <br /> <br />surface. Transects were resurveyed in April 1997, and plots were overlain to visually <br /> <br />compare changes in bed geometry. <br /> <br />Calculating Effective Discharge From Sediment Records <br /> <br />Effective discharge was determined by analyzing 847 suspended sediment <br /> <br />measurements made at the Watson gage. Sediment transport measurements were made <br /> <br /> <br />by the USGS between 1975 and 1990. A sediment rating relationship was developed by <br /> <br /> <br />fitting a best fit power function to a plot of the 10glO of daily suspended sediment in <br /> <br /> <br />kilograms/day vs. the 10glO of discharge in cubic meters per second. For the reach near <br /> <br />the Watson gage, this relationship was found to be: <br /> <br />Qsed = 931.63Q2205 (2) <br />where Qsed is sediment transport in kilograms/day, and Q is discharge in cubic meters per <br /> <br />second. Using the sediment rating relation, the amount of sediment transported by given <br /> <br />increments of discharge was determined. A flow duration curve developed from <br /> <br />approximately 76 years of daily discharge values was then used to determine what <br /> <br />percentage of time a given discharge occurs for the long-term average. The percentage <br /> <br />of time a given discharge occurs was multiplied by the sediment transported by that <br /> <br />magnitude of discharge, and the resulting product was plotted against discharge. The <br />13 <br />