Assessment of Submerged Structures for Coastal Protection in a Low Wave Energy Environment

Introduction

Beach erosion only becomes a problem when society – perhaps unwittingly – places

boundaries or infrastructure in a zone that is experiencing net long term erosion. Since the

process may be gradual and/or linked to climatic cycles, the risk to society due to beach

erosion may not be revealed until years or decades after particular sites have been

established. Coastal structures provide either direct (e.g. seawalls) or indirect (e.g. submerged

breakwater) protection of beaches and can be designed to provide varying degrees of

overtopping, wave breaking and wave transmission. The changes to local hydrodynamics and

sediment transport induced by such structures can result in a shoreline that is wider and in a