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projection transfer machine to adjust the photographic scale. To maintain transfer accuracy, roads, trails, and creeks were aligned in the photographs and map bases. The river channel was then digitized into a GIS using a digitizing tablet and puck. River channel surface area was determined for each reach by year. The length of each river reach was calculated by digitizing the center line of the channel for each data set. Channel surface area was divided by this length to calculate channel width. Measuring Sediment Transport Sediment data collection for this study began in 1986 at three locations within study reach 1. At sample point A, 15 samples over a discharge range of 30.6 cubic meters per second to 292.5 cubic meters per second were collected. At site B, 18 samples over a range of 31.3 cubic meters per second to 305.5 cubic meters per second were collected. At site C, 16 samples were collected over the range of 75.0 cubic meters per second to 393.4 cubic meters per second. Discharge and sediment samples were obtained using boat-mounted equipment including: • a Marsh-McBirney velocity meter (model 201) • a model A-55 depth sounding reel • a D-49 suspended sediment sampler • a BMH-60 bed material sampler • a calibrated tagline Water surface slope for a reach length of about one channel width was measured during each sampling period. The median diameter of the Green River bed material at the three sampling sites ranged from 0.25 millimeter at site B to 0.40 millimeter at site A. About 1 percent of the bed was made up of particles smaller than sand size. Gravel comprised about 1 to 3 percent of the bed. Thus, the bed-material load, that portion of the total sediment load found in bed materials of the Green River channel, is essentially equal to the sand-sized portion of the total sediment load. Bed-material load is defined for this study as that portion of the total sediment load coarser than 0.0625 millimeter. Using the Modified Einstein procedure (Colby and Hembree, 1955), the bed-material load discharge was computed for each sample collected at the three sampling locations. Figure 2 contains the computed sand loads for the samples collected at sites A and B and the suspended sand loads measured at gauge 09261000 from 1951 to 1986. The data collected from 1986 to 1988 at these two sites fall within the scatter of the gauge data. Thus, a suspended sand load rating curve was developed for the data from gauge 09261000 and used to describe the bed-material load transport at these sample sites (table 1). A satisfactory rating curve was developed using a power function with an empirically derived offset value. 5