This study clarifies how foreshore replenishment in the near future can contribute to a '' natural '' coastal security for conservation and nature. The ecological functioning of the beach and surf zone as parts of the coast base is up to now not sufficiently clear. We expect that this study raises the debate about the possible impact on the natural sand replenishment on the Belgian coast for a more objective and more scientific level. During the study, benthic indicators used to assess the environmental impact and the existing predictive model for supplementation effects further refined.