Emergency Management Officer Hawaii Dept. of Transportation Honolulu, Hawaii, United States
While Hawaii Department of Transportation (HDOT) is working hard to improve the state's traffic infrastructure, traffic counts continue to rise and Hawaii's roads are busier than ever. Day-to-day traffic congestion could become deadly if rapid evacuation is required. After a tsunami warning in Hawaii on 7/29/25 caused massive gridlock, HDOT recognized that although everyone was able to evacuate in time for this summer event, that might not be the case during the school year, when school-related traffic regularly contributes to congestion. Other jurisdictions' lessons learned from hurricane evacuation planning proved of limited applicability to this problem, and so an innovative approach was developed. HDOT purchased proprietary data to understand the trips that travelers took on the day of the event and then used peak traffic data to create a new baseline. Traffic management operations were then applied to the new baseline to determine the effectiveness of various mitigation strategies. Based on that analysis, HDOT concluded that traffic management alone is insufficient to ensure that all residents and visitors can evacuate by car in time for all worst-case scenarios. HDOT is now working closely with federal, state, and local agencies as well as the private sector to integrate public outreach and interagency coordination with traffic management solutions to reduce traffic demands and optimize existing infrastructure to maximize the effectiveness of future tsunami evacuations.
