Evaluation of the costs and benefits of natural and grey infrastructures for the protection of the Lake Erie shoreline

ABSTRACT: Approximately 75% of Ohio’s Lake Erie shoreline is protected by grey infrastructures (such as seawalls and breakwaters), which can alter natural coastal processes and disrupt coastal ecosystems. Recently, natural infrastructures providing a more natural/sustainable shoreline environment have attracted interest in the coastal engineering community. However, a lack of research-based evidence demonstrating the long-term benefits of using natural infrastructures has limited their use and promotion. This study evaluates costs/benefits for adopting natural versus grey infrastructures to protect Lake Erie shorelines. A cost-benefit analysis comparing three natural infrastructures (vegetated sand dunes, beach nourishment, and living shorelines) and five grey infrastructures (seawalls, breakwaters, groins, bulkheads and revetments) provides a quantitative understanding of the long-term costs/benefits associated with each approach. A survey of local professionals shows the advantages of natural infrastructures in terms of cost savings and environmental/ecological protection.