More Sand to the Shorelines of the Wadden Sea Harmonizing Coastal Defense with Habitat Dynamics

In the Wadden Sea, dynamic shoreline habitats have suffered substantial losses, squeezed between a rigid coastal architecture and a rising sea level. Shore replenishments with sand taken from the bottom of the North Sea would have a wide potential to restore lost habitats and species diversity seaward of dykes, bulkheads and eroding shorelines. Such an artificial sand supply has multiple advantages. It dissipates wave energy and may appease the hunger for sand caused by sea level rise. At sheltered shores, the longevity of nourished sand deposits will be sufficient to allow for a development of natural geomorphics and biotic successions. The aesthetic value and the touristic reputation of the coast will improve. It is assumed that about half of the shore length may be suitable for replenishments, preventing erosion, covering shoreline petrifications and replacing land reclamation fields. However, before such a large-scale management action is initiated, assumptions on the coastal sediment budget and implications on coastal ecology need to be scientifically explored and experimental replenishments need to be analyzed. The project may become a key issue of an integrated coastal management at developed sandy coastlines.