The cost of coastal protection: A comparison of shore stabilization approaches

摘要

The costs associated with implementing and maintaining shoreline structures is a critical element of coastal planning and decision-making. However, quantitative data comparing even the most common shoreline protection approaches are scarce to non-existent, particularly at scales relevant to waterfront homeowners. Here, we provide quantitative estimates of initial construction costs for common shore protection approaches by synthesizing existing literature and the results of socioeconomic surveys in Alabama, Florida, and North Carolina reflecting over 1,000 waterfront homeowners across 20 coastal counties. A review of available cost estimates revealed tremendous variability that, while likely explainable by scale and context, challenge informed decision-making by waterfront residents. The most prevalent estuarine shoreline protection strategies in North Carolina and Alabama were bulkheads (67% in North Carolina to 64% in Alabama), while bulkheads combined with riprap revetments were the most common approach in Florida (42%). More respondents in North Carolina reported having natural shorelines (65%) or living shorelines (1%) than Alabama (33% and 0%, respectively) or Florida (31% and 0%, respectively). A common thread across all states was that bulkheads, both with and without riprap revetments, were the most locally expensive to install. Recent research also indicates that bulkhead shorelines are damaged more frequently and can be more expensive to repair and maintain than other shore types, such as riprap or natural marsh shorelines. Collectively, these data show that the most common shoreline protection strategy, bulkheads (with and without riprap), may also be the most costly.