Monitoring morphology of the sand engine leeside using Argus' cBathy

Abstract

The Sand Engine is a mega-nourishment constructed in 2011 with the purpose of replenishing the surrounding southern Dutch coast by exploiting the strength of local alongshore currents for the next 20 years. Long term monitoring of the Sand Engine depends upon remote sensing coupled with in-situ measurements due to both its large spatial and temporal scales and variability. Herein, emphasis is made upon quantitatively and qualitatively observing the effects of this mega-nourishment upon its leeward side in the direction of the predominant alongshore current. One of the first applications of cBathy along the Dutch coast shows promising results for this remote technique to capture morphodynamics within the area over the coming years. cBathy is an algorithm developed to make estimations of nearshore bathymetry based upon the celerity of the propagating wave field extracted from Argus coastal images. So far, analysis shows that the Dutch wave climate variability influences hourly cBathy depth approximations, however running average depth estimations yield small deviation compared with a measured ground truth bathymetry of the area.