Coastline modelling - Phase III : investigation of the influence of model schematisation on a hindcast for the coast of Domburg

This report describes the modelling of coastline evolution at Domburg with the coastline models UNIBEST-CL+ and PONTOS. The main aim is to distinguish the relevance of modelling choices for the performance of a coastline model in this area. An important aspect concerned the modelling of the protrusion at Domburg. This is the third phase of a series of studies that investigate coastline modelling. With respect to the ability of the models it was found that the uncalibrated UNIBEST-CL+ model with nearshore wave conditions performed well for the considered case study at Domburg. The PONTOS model requires a robust implementation of nearshore wave conditions to resolve detailed coastline features such as at Domburg. In the present version, calibration of the alongshore transport is needed to obtain a good alongshore redistribution of sediment within PONTOS. A synthesis of the results of the Phase I to III studies is provided, which gives an overview of the relevance of model components of coastline models. The relevance of specific processes is also explained in relation to the considered typical coastal situation. It is recommended to investigate the ability of the coastline models for these situations.