Modelling Dutch lower shoreface sand transport

The objective of this study is to estimate the net sand transport rates on the Dutch lower shoreface, with water depths between ~15 and 25 m, and to unravel the underlying mechanisms. In the framework of the Kustgenese-2.0 (KG2) programme, the sand transport at the Dutch lower shoreface is assessed by combining field measurements, 1D, 2D and 3D models and expert judgement. This report focusses on the validation of the models with field measurements and model computations for five years. We use two different modelling approaches. The first includes the interaction of waves, flow, and the resulting sand transport (online approach). In the second approach, the waves, flow and the transport of sand are calculated separately and independently and there is no feedback between the processes (offline approach). Chapter 2 describes the applied methodology, including the measurements used and models applied. Chapter 3 presents a hydrodynamic validation of the models by comparing modelled and measured waves and velocities. Chapter 4 quantifies the sensitivity of various transport modelling approaches. Chapter 5 analyses the computed transports at the Dutch lower shoreface for a period of 5 years. Chapter 6 summarizes the results and presents conclusions and recommendations.