This project examines the effectives of the 100-year floodplain in predicting property damages from floods and offers improved criteria for assessing risk of inundation in low-lying coastal areas. As flood losses continue to increase in the United States, recent evidence suggests that the 100-year floodplain (the primary marker of flood risk and mitigation) is neither accurate nor sufficient in guiding communities and household decisions to mitigate the adverse impacts of floods. The inability of the floodplain designation to effectively capture the likelihood of property loss has left potentially millions of property owners unaware of the flood risk and has made it more difficult for local decision makers to ensure community development occurs in a resilient manner. First, the record of insured property damage at the household level from 2000-2009 will be spatially examined for a sample of coastal counties along the Gulf of Mexico. Second, statistical models to predict insured property damage from floods will be analyzed using proximity and built environment measures not traditionally used to determine floodplain boundaries. Finally, a survey will be conducted of households claiming losses both in and out of the floodplain to understand the perceptions of flood risks and motivations to mitigate their potential adverse impacts.
This research will provide important information to decision makers on how to implement more precise strategies to reduce the costs of floods at the local level. An improved understanding of flood risk will enable localities to better protect themselves against loss of property and lives in coastal areas. Research findings will also help individuals living outside the floodplain, but still at high risk for flood damages reduce the chances they will experience devastating losses in the future. To this end, a major part of the research project will be to deliver findings that can be easily accessed and understood by both public officials and local residents. First, data on flood loss and areas of risk will be integrated with an existing web-based GIS system that currently serves as a technical assistance and outreach tool. Second, local neighborhoods that have become hotspots of flood loss will be worked with to increase awareness of the problem and provide options for reducing future loss. Third, results from the study will be brought into the classroom as part of graduate and undergraduate studies across two college campuses. These approaches will ensure the research findings assist local governments and individual households on how to better reduce the negative impacts of coastal flooding in the US.
This project focused on flood risk reduction for communities along the Gulf of Mexico coast. We examined the causes, consequences, and policy implications of increasing flooding and flood impacts over an eleven year period. Analysis included: 1) mapping of property damage and identification of flood hot spots; 2) surveys of residents on their perceptions and household adjustments in response to floods; and 3) identification of the effectiveness of different mitigation strategies in terms of reducing observed flood losses. Results from the project will lead to a better understanding of how to reduce flood risk and related property loss at the local level. Findings will also inform decision makers on how to avoid flood losses in the future, particularly as vulnerability to coastal storms increases. Key findings of the project include: - Harris County, TX is the most vulnerable and flood-damaged jurisdiction along the Gulf of Mexico coast. - Elevation of structures above base flood and protection of open space in the floodplain are the most effective strategies for reducing flood damage. - On average, approximately 30 percent of insured flood losses across the Gulf of Mexico coast are located outside the 100-year floodplain. - Generally, a resident located outside the 100-year floodplain who has voluntarily purchased federal flood insurance can be characterized, on average, as more highly educated, relatively wealthy, and a long-time resident who thinks about flood hazard relatively infrequently but who, nonetheless, thinks flood insurance is relatively affordable.