Ecological indicators of flood risk along the Gulf of Mexico

Despite mounting economic losses from both acute and chronic flood events in coastal areas of the U.S., little empirical research has been conducted on the importance of existing landscape-level ecological components in mitigating the economic impacts to vulnerable coastal communities over the long term. In recognition of this lack of knowledge base, we examine several ecological indicators across 144 counties bordering the Gulf of Mexico. Specifically, we identify and measure the following four indicators: floodplain area, soil porosity, naturally occurring wetlands, and pervious surfaces. We then statistically test the degree to which these indicators reduce insured flood losses observed across the study area over a five-year period from 2001 to 2005. Results based on multiple regression models controlling for various environmental and socioeconomic characteristics support the notion that certain features of the natural environment help mitigate the negative economic consequences that arise from floods. The findings provide guidance to local and regional policy makers on where to guide future development. Reducing the amount of flood losses helps building more flood-resilient human communities along the Gulf coast not only in terms of economic savings but also to reduce human loss.

▸ Measure and statistically analyze the impact of ecological indicators of flood risk. ▸ Examine 144 counties/parishes along the Gulf of Mexico, USA coast. ▸ Spatially targeting future development in areas outside of floodplain boundaries is critical for flood-resilient communities. ▸ Loss of naturally occurring wetlands along the Gulf coast is another key ecological indicator related to flooding. ▸ Soil porosity is an influential but overlooked landscape characteristic contributing to the degree to which coastal communities incur flood losses.