R. McCall1*, A. de Bakker1, L. Coumou2, H. Steetzel2, N. van Kuik3, R. Wilmink3, S. Pluis3
1 Deltares; 2 Arcadis, 3 Rijkswaterstaat WVL
Sandy coasts (e.g., beaches and dunes) protect large stretches of the Dutch coast against flooding. To maintain an adequate level of flood protection, primary flood defences are regularly evaluated as prescribed by the Dutch Water Law. The safety assessment methodology for sandy coasts was recently updated within the framework of the program BOI (Assessment and Design of Flood Defences). This process contributed to the identification of key research gaps in the source-pathway-receptor-consequence chain of the current coastal flood risk assessment in the Netherlands.
In Q4 of 2022, Deltares, Arcadis and Rijkswaterstaat organised workshops with experts on sandy coasts and flood risk in the Netherlands to identify key areas of future research. The results of these workshops were used to develop a knowledge agenda for research within the Rijkswaterstaat "Kennis voor Keringen" program, focussing on the need to improve flood risk assessments for purely sandy coasts (i.e., dune coasts), as well as hybrid (e.g., dike-in-dune) coastal defences.
At the NCK days 2023, we would like to share these key research gaps with interested parties and discuss upcoming or potential research that can contribute to an improved safety assessment of the Dutch coast.
Figure 1: Categorization of research questions in the knowledge agenda in sources (hydraulic loads; blue), pathways (dune erosion, green; further failure mechanisms, black), and receptors and consequences (flood risk, red) for dune coasts and hybrid defences.