Short description and objective of the project: Scour holes are large, local perturbations in the river bed. They have been observed all over the world, for example in the Mahakan river in Indonesia (Vermeulen et al., 2014), the Mississippi river in the Unites States (Nittrouer et al., 2011), and in the Rhine-Meuse Estuary in the Netherlands (Huismans et al., 2021). Human interventions might trigger the formation of these deep scour holes. For example, in the Meuse river in the southern part of the Netherlands, deep scour holes formed after the summer flood in 2021. One of the triggers for their formation was the downstream widening of the river by the construction of some side channels (Barneveld et al., 2025). The upstream part of the river reach functioned as a bottleneck in which flow velocities locally accelerated, resulted in strong erosion. Consequently, large scour holes with depth up to 15 meters developed. One of them uncovered a pipeline. Another scour hole threated the stability of a ferry landing, such that the ferry was taken out of service. For both scour holes, rapid action was required to ensure flood safety. Therefore, for adequate flood risk management it is crucial to understand the behaviour of these scour holes, on the short-term but also on the long-term. A first step to this understanding is getting insight into the hydrodynamics in a scour hole. Within the framework of the Future Flood Risk Management research project Rijkswaterstaat performed a unique measurement campaign in one of the scour holes in the Dutch Waal River, in November 2025. They collected flow velocities at different locations around the scour hole at Erlecom (see Figure 1). Besides this unique set of flow velocity measurements in a scour hole (Figure 2), the bathymetry in and around the scour hole was measured. We are urgently looking for an MSc student interested in river morphology, flow processes and data analysis to study this unique set of measurements. Understanding the flow processes in the scour hole at Erlecom will provide insight in the general flow patters that can be observed in scour holes and will assist in the future management of the Rhine-Meuse Delta.
1. Analysing the flow velocity measurement of Rijkswaterstaat and identifying the important flow structures. Since, there is a lot of data analysis involved in this assignment, a basic understanding of Python is an advantage. However, the analysis can also be done in Excel. The start of the MSc thesis should be in February 2026 or later. References (optional): Barneveld, H. J., Frings, R. M., Mosselman, E., Venditti, J. G., Kleinhans, M. G., Blom, A., Schielen, R. M. J., Toonen, W. H. J., Meijer, D., & Paarlberg, A. J. (2025). Extreme river flood exposes latent erosion risk. Nature, 644(8076), 391–397. |
