Abstract
Roadway flood inundation can impede travel to work, the distribution of goods, public access to essential services, and emergency response operations. Knowing where and when roads may flood is essential for emergency planning as well as the implementation of the infrastructure upgrades necessary for climate change adaptation to coastal flooding. This report details a novel approach for estimating the extent and depth of roadway inundation using light detection and ranging (LiDAR) derived roadway surface elevations. A desktop analysis was conducted utilizing this approach to provide a first order assessment of coastal flooding impacts under current and future flood scenarios for New Jersey. The southern coastal counties have the most roadways, hurricane evacuation routes, and bridges vulnerable to potential inundation in the three scenarios used in this analysis. These vulnerabilities continue to increase considerably in the potential miles and bridges inundated between the 2050 and 2100 scenarios suggesting that preparing for a projected 2 feet of sea level rise in 2050 alone may not be sufficient to prepare for the significant increase in permanent inundation that may be experienced 50 years later. Four data layers produced from this analysis have been made publicly available. The findings of this analysis may be used by transportation and emergency planners, flood plain managers, and the public to understand the current and future flood risk potential posed to coastal roadways in New Jersey.