An Approach For Appraising The Accuracy Of Suspended Sediment Data PDF Download

A procedure for measuring total sediment discharge using point-source suspended-sediment data was developed. The proposed procedure, TSL (Total Sediment Load), was tested with field data from the Niobrara River at Cody, NE; Fivemile Creek at Shoshoni, WY; the Middle Loup River near Dunning, NE; the Rio Grande Conveyance channel near Bernardo, NM; and Goodwin Creek near Oxford, MS. The TSL procedure was compared to the modified Einstein procedure (MEP), which uses depth-integrated suspended-sediment data for measuring total sediment discharge. The TSL procedure provides total sediment load measurements that are similar in magnitude to both turbulence flume measurements of total sediment load and MEP measurements. The similarity in results for the TSL procedure, the total sediment load measurements, and the MEP demonstrate the use of the TSL procedure as an alternative to depth integrated suspended-sediment sampling. Results of the TSL procedure are more reliable when the point suspended-sediment samples are collected in the lower flow depth. The TSL procedure was tested and found to be reliable using point samples collected in the lower 20 to 45 percent flow depth. The assessments of the reviewed data sets highlight advantages for selecting the TSL procedure over the MEP: realistic sediment load measurements, greater control in obtaining suspended-sediment samples, automatic sampling, the collection of near-continuous measurements, and time integration for determining the true sediment transport. Also, the use of point-source suspended-sediment samples requires less time in the field and lower sediment sampling costs. (fr).