Modeling and Managing the Long-term Effects of Artificial Dune Construction in the Outer Banks of North Carolina

The goal of this paper is to gain a better understanding of long-term interactions between natural processes and human activities, and how protective measures produce long-term, unintended consequences. Protective measures can disrupt natural processes in such a way that can intensify property damages from natural hazards. Current management practices aimed at defending transportation infrastructure in the Outer Banks of North Carolina are creating such long-term effects. A numerical model examines the long-term, coupled geomorphic and economic consequences of constructing and maintaining artificial dunes. By subjecting a simulated barrier island to a probabilistic storm climate, storm impacts are described in terms of probability distributions of outcomes, which can be translated into quantifiable risk to coastal development. Furthermore, the evolution of this risk over time is investigated as economic activities-and subsequent mitigation measures-are impacted by and alter natural processes of barrier island evolution. Given the magnitude of change that coastal systems will be subject to under climate change, current management strategies designed to maintain system stability are certainly unsustainable and may even be self-defeating in the long-term.