Field data describing the movement and storage of sediment in the East Fork River, Wyoming; Part I, River hydraulics and sediment transport, 1979

Bed-material gradation and water-surface slope were determined for a 3.3-kilometer reach of East Fork River, Wyo. During peak snowmelt runoff, frequent measurements of water discharge and sediment-transport rate provided data describing the inflow and outflow of water and sediment. In spring 1979, bankfull stage was exceeded on 8 days. Maximum discharge was about 32 cubic meters per second, which has a recurrence interval of about 2 years. The median particle size of bed material is 1.28 millimeters; the 35 and 65 percentiles are represented by diameters of 0.50 and 2.88 millimeters, respectively. The average water-surface slope in the reach is 0.0007 and varies little with river stage. Bedload-transport rates ranged from a little less than 0.001 to a little more than 0.1 kilograms per meter of channel width per second. Median bedload grain size, with several exceptions, ranged from 0.4 to 1.5 millimeters. Gravel-size particles generally constituted 10 to 40% of the bedload. Suspended-sediment concentrations ranged from 6 to 95 milligrams per liter. Suspended sediment smaller than sand constited about half the measured suspended sediment, ranging from 17 to 81%. (USGS)