HRI's Coastal and Marine Geospatial Lab (CMGL) is assessing the impacts of Hurricane Ike in terms of Gulf shoreline erosion and recovery processes. Shortly after the storm, the CMGL began analyzing pre- and post-storm vertical aerial photography and working with the Texas General Land Office, the U.S. Geological Survey, the U.S. Army Corps of Engineers, and The University of Texas at Austin (UT) to coordinate ground and airborne surveys.

Many people recall when Hurricane Ike struck the upper Texas coast on September 13, 2008. Ike made landfall on the eastern end of Galveston Island as a large and strong category 2 hurricane. Sustained winds were nearly 110 mph and storm surge reached at least 17 feet, inundating the barrier islands and pushing water miles inland.

In October, a field crew from HRI and UT Austin conducted surveys of the beaches along Galveston Island. In December, the HRI/UT team conducted an airborne lidar survey to acquire highly detailed and accurate topographic data of the Gulf shoreline.

Ike caused 40- to 90-meter shoreline retreat. Some of the sand eroded from the beaches and dunes was deposited on top of the barrier islands. The thickness of these extensive sand deposits was more than 60 cm in places and served to raise the elevation of the Gulf edge of the islands to compensate for long-term sea-level rise. HRI/UT surveys conducted along the west beach of Galveston Island one month after the storm revealed little beach recovery, and important questions remain regarding where and how long it will take for the

beaches and dunes to reestablish. Longer term research projects by HRI scientists will study the beach and dune recovery process and provide information and recommendations for managing the shoreline.

Other initial observations of the impact of Hurricane Ike include:

• Improved construction standards and evacuation procedures made Ike less damaging than it would have been.
• The extensive damage caused by Hurricane Ike, a category 2 hurricane, emphasizes that the Saffir-Simpson Hurricane Scale is not the best indicator for hurricane impacts.
• We are still building and rebuilding in hazardous locations.
• The upper Texas Gulf shoreline is highly vulnerable to storms and this vulnerability is increasing because of:
  • Ongoing shoreline retreat
  • Small or non-existent foredune complexes
  • New and old shoreline development
• Storm overwash deposits help maintain coastal environments undergoing long-term relative sea-level rise.
• “Rolling” setback policies that provide space for overwash deposition and dune development are needed.
• Levels of damage caused by Ike is just the beginning as we enter a period with likely increased frequency and strength of hurricanes that follows a period of intense coastal development.