Evacuation and Adaptation for Sea Level Rise

Sea level rise is becoming a major problem for transportation agencies. This study examines three issues: (1) identifying the impacts of sea level rise and storm surge on areas that may be evacuated from a hurricane, (2) evaluating microscopic and mesoscopic traffic simulation tools for evacuation scenarios, and (3) identifying adaptation strategies that could be useful for addressing sea level rise and protecting the road network. While hurricane evacuation notices are typically timed to attempt to clear evacuees from the roadways prior to the arrival of tropical storm force (or greater) winds, low lying areas must also be concerned about storm surge flooding, particularly for surge forerunners and as sea levels rise. This report uses water level time series data from the U.S. Army Corps of Engineers to identify the roads and areas of Norfolk and Virginia Beach vulnerable to storm surge flooding and sea level rise. The data were analyzed in conjunction with the terrain model. This study investigates three conditions, including (1) the base condition which is defined as the condition under storms modeled on mean sea level with wave effects, no sea level change, no astronomical tides, (2) the base condition plus tide, and (3) the base condition plus tide and 1.0 meter of sea level rise. For the analysis process, geographic information systems (GIS) was used to locate flooded areas and roads. Conditions 1 and 2 had similar results. The ranges of highest flood levels for conditions 2 and 3 are 1.5 to 4.5 meters and 2.5 to 5.2 meters, respectively. The percentages of flooded risk areas for condition 2 ranges from 4% to 27%, while for condition 3 the range is 22% to 26% before the peak period, and more than half of the area is flooded during the peak period. This report compared the microscopic traffic simulation tool INTEGRATION and mesoscopic tool MATSim for modeling different evacuation scenarios. The models were compared based on the estimated evacuation time, average trip duration, and cumulative arrival plot. The estimated evacuation times of both INTEGRATION and MATSim were close to each other since the demand of all scenarios was less than the capacity of network. The evaluation showed a difference between the two models in the average trip duration. In INTEGRATION, the average trip duration increased with increasing traffic demand levels and decreasing roadway capacities. On the other hand, the average trip duration using MATSim decreased with increasing total travel time. The trends for the cumulative arrival times for both were close to each other. MATSim served more vehicles than INTEGRATION did at the beginning of the stimulation. After that, both models served the same number of vehicles and these trends become closer to each other. These results seem to demonstrate that a tool like MATSim may produce erroneous conclusions if network-wide average results are desired. GIS was used to study the topography and storm surge forecast of the Hampton Boulevard corridor of Norfolk Virginia. Potential adaptations were developed including Flood Barriers, Bio-retention Rain Garden Systems, and Flood walls to suit the area. Ultimately the final decisions were made based on how feasible it was and cost effective on a long term bases.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Figures; Maps; Photos; References; Tables;
  • Pagination: 62p

Subject/Index Terms

Filing Info

  • Accession Number: 01663148
  • Record Type: Publication
  • Contract Numbers: DTRT13-G-UTC33
  • Files: UTC, TRIS, ATRI, USDOT
  • Created Date: Mar 20 2018 5:09PM