Category:Portable streamer traps for longshore sediment transport measurement

Summary

In this category, we present a new portable streamer trap to measure point-Depth-Integrated Longshore Sediment Transport (DIST) on MSG beaches.

• Measurement of the longshore sediment transport rate in the surf zone remains one of the great challenges in coastal engineering and coastal sciences.
• Streamer traps for sand beaches have proven useful in the past, but are not suitable for Mixed Sand and Gravel (MSG) beaches.
• This category describes a portable depth integrated, streamer trap designed to measure the depth-integrated combined bed load and suspended longshore sediment transport on MSG beaches.
• The device has been tested in the field under moderate wave conditions at Minsmere, UK.
• Empirical efficiency of wave breaking and bed load are several orders of magnitude larger than for uniform fine sand values.

History

DIST was first developed in 2020^[1] with the aim to investigate the field performance of the device under moderate wave conditions (i.e. wave heights less than 1 m). To test the performance of the device, we compare measured to simulated rates using the depth-integrated and wave averaged cross shore numerical model CSHORE (Kobayashi, 2016). During the experiment, offshore wave forcing was measured by a directional wave buoy located about 4 km seaward of the study site. Current velocity and water levels were measured with an Acoustic Doppler Velocimeter (ADV) and a pressure sensor anchored to a fixed rig, which was well within the surf zone during the full tidal cycle. A pressure sensor was also attached to the portable streamer trap to provide information relative to water depth and water surface elevation at the trap location.

References