Shoreline response to submerged structures: A review

Submerged coastal structures are widely perceived to be capable of providing beach protection, without the adverse impacts (including loss of beach amenity and aesthetic considerations) often associated with more conventional structures such as revetments and groynes. In addition, there is growing interest in the concept that the layout and cross-section of submerged coastal protection structures can be optimised to also enhance local surfing conditions. However, as submerged structures have only rarely been adopted for beach protection, the shoreline response to these structures is not well understood at present. Therefore, this review of the available published literature was undertaken with the aim of investigating the environmental and structural parameters governing shoreline response to submerged structures.. gleaned from the results of field, laboratory and numerical studies undertaken to date. The review reveals that, contrary to expectations, a majority of the submerged structures constructed to date have resulted in shoreline erosion in their fee. Furthermore, the key environmental and structural parameters governing the mode (i.e. erosion or accretion) and the magnitude (i.e. size of salient) of shoreline response to submerged structures are yet to be identified. Although submerged coastal structures offer the potential for low aesthetic impact incorporating multi-function design, until the response of the adjacent shoreline to submerged structures is better resolved, their use is likely to remain relatively limited. (c) 2005 Elsevier B.V. All rights reserved.