Sand nourishment – Hondsbossche Dunes

The Hondsbossche and Pettemer sea dike no longer met current safety standards. Therefore the dike was reinforced in 2015 with a soft, natural barrier of 30 million cubic metres of sand on the seaside of the dike. It was renamed ‘Hondsbossche Dunes’. The construction presented the unique opportunity to study the morphodynamics of dunes and natural dynamics following a dune reconstruction. The role of HKV in the research programme was monitoring of the morphodynamics over multiple years and describing lessons learned for future dune reconstructions.

The design consists of a soft shallow foreshore (the beach) and a varied artificial dune landscape that has the potential to develop in valuable Nature 2000 habitats. Together, these connected systems make up the primary flood defence and provide the desired spatial quality. The Ecoshape innovation project, is a three-year interdisciplinary study of the area focussing on the development and perception of nature and the morphological development of the area. The aim of the innovation project is to learn more about efficient sand-nourishment with added value for nature and leisure. The research programme includes three themes:

A. Predictability in the development of engineered habitats

B. Optimizing design and morphological evolution

C. Perception of local community and visitors

An improved understanding of these issues is crucial to the elaboration of an evaluation framework for decision-making about sandy solutions to coastal fortifications. The project also offers a clearer picture of the possibilities for the design, management and maintenance of these sandy structures.

Photo was taken in 2016 after the reinforcement.