Nature-based Urban Flood Resilience: a policy analysis of natural flood mitigation measures in sea level rise planning in New Orleans, New York City, and San Francisco

Abstract

Sea level rise (SLR) and severe weather events have already exposed the vulnerability of coastal cities to flood events. Regional planning bodies are developing comprehensive plans to build resiliency utilizing both hardened and natural flood mitigation measures. While the plans use living shorelines and wetland restoration to buffer coastal regions, land managers have uncertainty to the level of protection these measures provide and a bias to maintain hardened shorelines and levee infrastructure. In addition, there are barriers to implementation of SLR adaptation plans in permitting, funding and land tenure. Research methods for the project include a literature review of resiliency planning documents and related articles, as well as interviews with resiliency planning staff in the case study areas of New York, San Francisco, and New Orleans. Policy recommendations are made that include: standardizing economic valuation and performance matrices of natural flood barriers, simplifying agency approvals, developing managed retreat practices and project migration zones, and increasing federal funding while identifying local resources for adaptation projects.