Combined effect of land subsidence and sea level rise poses a significant longterm threat of coastal land inundation. It jeopardizes infrastructure located in these areas. A detailed GIS method that adopts historical land elevation data of a region collected by a continuous monitoring and surveying network is discussed and detailed in this paper. Authors simulated the risks of land inundation for varying periods in future and identified at-risk infrastructure located in the affected area with the help of the GIS. The risks were forecasted for next 100 years, with 10-year increments starting from 2014. Some of the infrastructure assets located in some of the coastal areas of Gulf of Mexico were chosen as an example of at-risks assets for this study. Authorities such as state departments of transportation would use this approach in identifying the at-risk infrastructure and plan for their short-term and long-term response accordingly.