Franziska Staudt , Rik Gijsman, Caroline Ganal, Finn Mielck, Johanna Wolbring, H. Christian Hass, Nils Goseberg, Holger Schüttrumpf, Torsten Schlurmann, Stefan Schimmels

Beach nourishments are a widely used method to mitigate erosion along flood-prone sandy shorelines. In contrast to hard coastal protection structures, nourishments are considered as soft engineering, although little is known about the cumulative, long-term environmental effects of both marine sediment extraction and nourishment activities. Recent endeavours to sustain the marine ecosystem and research results on the environmental impact of sediment extraction and nourishment activities are driving the need for a comprehensive up-to-date review of beach nourishment practice, and to evaluate the physical and ecological sustainability of these activities. While existing reviews of nourishment practice have focused on the general design (motivation, techniques and methods, international overview of sites and volumes) as well as legal and financial aspects, this study reviews and compares not only nourishment practice but also the accompanying assessment and monitoring of environmental impacts in a number of developed countries around the world. The review shows differences in coastal management strategies and legislation as well as large dissimilarities in the licensing process for both marine sediment extraction and nourishment activities. The spatial disturbance of the marine environment that is considered a significant impact varies substantially between countries. Combined with the large uncertainties of the long-term ecological and geomorphological impacts, these results question the assumption that nourishments are a sustainable method for coastal protection.