The purpose of this report is twofold, i.e. reporting the setup and outcomes of the Wijmeers experiment for further (model) analysis and providing outlook for future experiments.
The height of the dike was around 3 m above the ground level of the hinterland, and the width of the crest was 6 m. However, the initiation gully reached only 1.5 m above ground level. During the experiments the following aspects were monitored: breach growth in width, water levels just upstream and downstream of the dike, water pressures within the dike and (to some extend) flow velocities within the breach. Breach growth in width occurred slowly. Therefore measurements continued for almost 2 months. Outcomes can be used for a better understanding of the complex physical processes of embankment breaching for detailed model development and validation as for the optimization of dike design and maintenance strategies.
Allowing overflow and wave overtopping in time (as a climate resilience measure) introduces an additional failure mechanism to account for when designing and maintaining dikes. Incorporating such strategic choices within dike management will need improved maintenance strategies as well as experience with managed and emergency response measures. In addition to filling gaps of knowledge regarding strength of vegetation cover, breach formation and growth, future dike experiments will allow to train skills and gain experience with state-of-the-art managed and emergency response measures.