Coastal defense and beach renovation

Abstract

Coastal erosion is a worldwide occurrence principally along sea shores but also along many lake shorelines. It has been reported in the literature for several decades. It encompasses considerable economic consequences, endangering, for instance, valuable properties. The rise in water level is a major cause of the phenomenon, but anthropic actions have also played an important part. Traditionally, eroding coastlines have been protected by civil engineering structures ranging from groins to seawalls. This approach, while providing local relief, has proven to generally transfer the problem from one geographical site to another. Replenishment of a depleted area by artificial nourishment, sometimes buttressed by some hard structures, has been tested and shown to help in rebuilding beaches and countering shore erosion. The largest such undertaking anywhere in the world has been carried out on the Belgian east coast. The successful results have led to a similar project on the west coast. This paper reviews various ‘hard’ defense approaches and describes beach nourishment at certain sites where it has been tried.