Issue:Cost Estimates for Flood Resilience and Protection Strategies in New York City

critical need tobetter prepare for future stormsurges and to anticipate future trends, such as climate change and socio-economic developments. The research presented in this report assesses the costs of six different flood management strategies to anticipate long-term challenges theCity will face. The proposed strategies vary from increasing resilience by upgrading building codes and introducing small scale protection measures, to creating green infrastructure as buffer zones and large protective engineering works such as storm surge barriers. The initial investment costs of alternative strategies vary between $11.6 and $23.1 bn, maximally. We show that a hybrid solution, combining protection of critical infrastructure and resilience measures that can be upgraded over time, is least expensive. However, with increasing risk in the future, storm surge barriers may become cost effective, as they can provid