The coast of Louisiana is under threat because of sea level rise and land subsidence. Sea water is encroaching deeper inland and as a result Louisiana is losing land at an alarming rate. The combined effect of sea level rise and land subsidence is variable spatially. This paper focuses on this combined effect in identifying the transportation infrastructure that is at risk of getting affected by the seawater inundation of the land.

This paper attempts to account for land elevation data monitored continuously at various locations along the coast of Louisiana and combining it with local sea level rise to delineate land that is projected to be underwater. The collected data points were converted in spatial data processed using GIS to identify the transportation infrastructure that is at risk for next 100 years, with 10-year increments starting from 2014. Open source data made available by federal agencies were processed using ArcGIS to develop spatial surfaces and intersect those surfaces with transportation data. The results suggest that the land subsidence is having greater impact on transportation infrastructure than sea level rise. It is projected that by year of 2114, about 2,945 miles or 21% of the existing transportation infrastructure will be impacted because of the combined effect of land subsidence and rising sea level. This estimate does not take account of effectiveness of extensive levee system present in parts of coastal Louisiana.