“Alternative” shoreline erosion control devices: A review

Abstract

A variety of patented approaches have been devised in efforts to halt shoreline erosion. Commonly termed ‘alternative’ or ‘innovative’ technologies, these are typically variations on the traditional approaches. A categorization of these approaches is presented that identifies devices placed in the water and devices placed on the beach. These categories are further subdivided. Despite their innovative nature and the claims of their inventors and promoters, these devices suffer from a variety of weaknesses when deployed in the real world. We present a non-exhaustive list of 110 devices for which US patents were awarded since 1970. The view of success of ‘alternative’ devices often differs between reports made by the developer and those of the end-user and only in a few cases have objective assessments been made. Using a variety of sources we review experiences with artificial surfing reefs and beach drainage systems. We conclude that ‘alternative’ devices offer the same range of shortcomings as traditional shoreline stabilization approaches because of the inherent inability to control such a dynamic sedimentary environment and the failure to address the underlying causes of shoreline recession (sea level rise, sediment supply, other engineering structures, and the presence of infrastructure in the active coastal zone).