A System for Measuring Horizontal Sand Transport by Currents

Abstract

We describe a new sand trapping system which enables measurement of horizontal transport rates of suspended sand in the benthic boundary layer of multidirectional unsteady currents. A field test carried out through a tidal cycle in the tide-dominated shallow waters of the eastern English Channel demonstrates the utility of the new system. Amounts of sediment trapped in the different directions are compared with predictions by a simple theoretical approach. The applicability of the new system is then discussed. The net total transport rates and the net transport rates as a function of grain size appear complicated. They are characterized by significant cross-shore contributions maybe related to the cross-shore heterogeneity of the application area in terms of hydrodynamics and sediment suspension.

Although still pledged with uncertainties about directional sensitivity of the traps and induced flow disturbances, this new system appears a promising tool for future studies of sediment transport in coastal areas.