Building with Nature Hondsbossche en Pettemer Zeewering (KB-24-001-002)

This Ecoshape innovation project, partly funded by HWBP, HHNK, and EcoShape, evaluates how the reinforcement of the Hondsbossche and Pettemer Zeewering (HPZ) with an artificially created dune landscape in front of the old seadike [now called the Hondsbossche Duinen (HD)] functions. The purpose of the project is to promote the application of sandy flood defence (i.e. faster and more efficient solutions) by publishing the research results and experiences at HD with habitat development (Natura 2000) and environmental effects. It examines the predictability of the development of dune habitat types and the optimization of the safety design, also considering user perception. The predictability of habitat development in construction projects is important because clarity on the future development makes for less discussion and shortens the preparation time of the construction of a sandy reinforcement.

The physical design of the HD is slightly larger than would be strictly necessary (given the current design rules and water safety policy). If there is a widely supported view that the HD will remain sufficiently robust, future sandy coastal reinforcements could be down-sized. The idea that sandy flood defences are generally appreciated as an attractive, modern form of dike reinforcement seems to be confirmed by the HD. At the same time, the immediate environment may experience specific negative effects of these coastal solutions (e.g. sand nuisance).

The project results are relevant to management and design, and therefore of direct importance to:

- HHNK as manager (because the design and management of the HD and future flood defences can be better configured);

- HWBP / RWS as funding authority of current and future reinforcements (because they can increase the applicability of the concept of sandy solutions).