Validation of Bed-Load Transport Measurements with Time-Sequenced Bathymetric Data

Abstract

Advances in bathymetric data acquisition have made it possible to explore alternative methods for measuring bed-load transport in rivers. The method validated herein consists of measuring rates of bed scour by using time-sequenced bathymetric data. The validation is performed in a laboratory flume by comparing the measured rates of bed scour with direct measurements of bed-load transport. The bed forms in the flume are dunes traveling at nearly constant speed. The shape of the dunes remains nearly constant. No suspended load is present. The ranges for Froude and Rouse numbers are 0.24–0.50 and 4.6–10.4, respectively. The study shows that under the given conditions, bed-load transport determined from time-sequenced bathymetric data is equally accurate to that determined from measurements of bed-form amplitude and speed. Obtaining bed-load transport from time-sequenced bathymetric data is often more expedient than traditional methods.