UNDERSTANDING LOCAL IMPACTS OF SEA LEVEL RISE: A GIS-BASED ANALYSIS IN CHARLESTON, SC

There is clear scientific consensus that climate change is taking place and coastal communities will need to make decisions in the coming years about adapting to the impending impacts. Flooding due to astronomically high tides and heavy rain events is already a significant problem in the City of Charleston, SC. Climate variability and long term climate change, including accelerated sea level rise, could exacerbate flooding problems by increasing the frequency and the depth to which areas of Charleston are inundated. This project was designed to help to start the process of planning for climate related changes in the region. The goal was to develop materials that could be used for determining adaptation options and begin adaptation planning for the City of Charleston.

A GIS-based methodology was developed to map areas where flooding currently impacts buildings and infrastructure. Analyses of local and regional sea level rise were conducted using tidal gages from surrounding rivers, estuaries and the Charleston harbor. A maximum high tide linear sea level rise rate of .0046 meters per year was determined for the region. This rate did not include climate change scenarios or accelerations. Scenarios were developed on an ultra high resolution LIDAR model of the Charleston peninsula that projected current flooding problems in the areas based on increases in tidal / water table interactions. Finally, visualizations and maps of problem areas were developed for use in planning storm water management and infrastructure / property protection.