Methodology predicts effects of hurricanes on coastal roadways

Terra Daily: More than 60,000 miles of United States roadways are in the 100-year coastal floodplain, making them vulnerable to attacks from water surges and storm waves generated by hurricanes. A new study, in the latest issue of the Journal of Coastal Research, introduces methodology that integrates state-of-the-art models as effective tools for engineering design and hurricane emergency management.

According to U.S. census data, more than 50 percent of the population lives within 50 miles of the shoreline, and that coastal population continues to grow. In the last three decades, more than 37 million people, 19 million homes, and countless businesses have been added to coastal areas. These areas are under severe stress owing to increased human activities and climate change.

With the rapid development of computer technology, significant advances in modeling storm surges and surface waves have been made in coastal engineering over the last decade. The simulation and prediction of storm surges and waves are intrinsically complex.

In the study, the advanced surge model (ADCIRC), coupled with the wave model (SWAN), was used to construct the prediction and effects of Hurricane Georges on the Mobile Bay estuary in 1998. Agreement between the model and data of the poststorm survey was found, demonstrating the effectiveness of the wave and surge prediction on coastal roadways around shallow estuaries. The coupled wave and surge modeling system has also been used to simulate the storm surge and wind waves during Hurricane Katrina that caused the collapse of several coastal bridges.