Noordwijk - safeguarding the Dutch coastline

A rise in the sea level is expected as a result of climate change. The Netherlands' first and most important lines of defence against the North Sea are the sea dikes and the sand dunes. Recent assessments of the strength of these lines of defence have shown that the coastline has a couple of weak links needing immediate strengthening. One of these is the coastal dune at the popular seaside town of Noordwijk. Grontmij is providing services in relation to the strengthening of this.

The height of the dune is 1 m less than that which is required, over a length of approximately 1 km. A combination of interests (flood defence and local development) mean that the total length of the strengthening works and coastline adjustment will be approximately 3 km. The reinforcement of the coastline will be achieved by the construction of a sand-core dike with a basalton revetment complemented by a beach and foreshore replenishment using 1,5 million m3 of sand. This will result in dunes 50 m wider than the existing dunes and with a height of approximately 5 m (NAP +8.5 m). The new dike within the dunes provides not only the necessary level of safety but also creates high quality multifunctional spaces for recreation, business and leisure, in keeping with the new vision for the development of this seaside town. During the execution of this multi-disciplinary project many disciplines including hydraulic engineering, morphology, construction engineering, geotechnical engineering, ecology, economics, landscape architecture, communications, and the legal profession are being brought together, and many interests in the area are being taken into account. Grontmij is providing services in virtually all of the above-mentioned disciplines and is also supporting the client in both project and process management. Photography : Mieke Roth www.nowhow.nl