10-years evaluation of the Sand Motor : results of the Monitoring- and Evaluation Program (MEP) for the period 2011 to 2021

In 2011 the large-scale sand nourishment ‘The Sand Motor’ was constructed (21.5 million m3) with the aim of gaining experience with innovative nourishments that combine recreational, natural and coastal maintenance functions and strengthen the Delfland coast. Unique about the Sand Motor is that it can freely reshape over time as a result of natural coastal processes. Waves, tidal currents and wind redistribute the sand along the coast and to the dunes. The development of the Sand Motor in the period from 2011 to 2021 was evaluated for Rijkswaterstaat. The objectives in the Environmental Impact Assessment (EIA), that were set prior to the realization of the Sand Motor, are leading for this evaluation. These are: I. Stimulate natural dune growth at the coast of Delfland for the benefit of safety, nature and recreation; II. Develop knowledge and innovation; III. Add attractive (temporary) recreational and natural area. IV. Management objectives, aiming at recreational safety (e.g. for swimmers), impact of recreational use on nature and effects of the Sand Motor on groundwater, vegetation in the existing dunes and infrastructure.