Assessing the Long-Term Impact of Subsidence and Global Climate Change on Emergency Evacuation Routes in Coastal Louisiana

Climate Change Clearinghouse2012PDFTech ReportKent, Joshua D.Louisiana State University. Center for GeoInformaticsLouisiana State University, Baton RougeLouisianaCoastsEvacuationClimate changeSubsidence (Geology)ForecastingTransportation planningDisaster preparednessEmergency managementSustainable developmentGeotechnical engineeringSubsidence forecast models for coastal Louisiana were developed to estimate the change in surface elevations of evacuation routes for the years 2015, 2025, 2050, and 2100. Geophysical and anthropogenic subsidence estimates were derived from on-going empirical studies published in contemporary scientific literature. Forecasted elevation changes were subtracted from road surface elevation surveys. Individual road segments estimated to have surfaces at or below 0m in elevation (NAVD-88) were quantified by road class and parish. Additionally, the threshold for climate change susceptibility was evaluated relative to storm surge models published by the National Weather Service, which were used to identify and quantify evacuation routes vulnerable to surge inundation. The results from this analysis are presented by parish and reveal the modeled subsidence risks for the forecast years. Findings from this research can provide transportation engineers and emergency managers with data previously unavailable, which are applicable to evacuation modeling, hazard mitigation, environmental sustainability research, costal restoration efforts, and more.109