Soft Engineering for Coastal Protection: Natural Hazard Regulation

Abstract

Coastal wetlands, beaches and dunes have always played a role in the protection of coastal lowlands. Using their capability to attenuate waves and prevent erosion has gained more momentum in recent years. Critical to their design is an understanding how different parts of the coastal system function as one coastal protection system, with sediment sources and pathways as their basis. A dune depends on its beach, and salt marshes and mangroves depend on a muddy foreshore. Natural systems perform well under natural conditions, but less in the case of extreme storms. Combinations of soft and hard structures may provide the optimized design needed. It is important to design and value soft defenses as multifunctional assets in coastal development and to realign their design to the needs of local communities, so they are fully integrated and their management and long-term presence can be safeguarded. A major challenge is to convince engineers, that there are ‘hard’ arguments for using soft defenses so they are regarded as an engineering challenge.