Analysis of Transportation Disruptions from Recent Flooding and Volcanic Disasters in Hawai'i

The purpose of this paper is to describe, analyze, and compare disruptions to the transportation system from two recent disasters in Hawai'i. While they occurred on different islands (Kaua'i and Hawai'i) and resulted from different hazards (flooding and volcanic eruption), there are important commonalities due to the disruption of surface transportation and the consequences for evacuation and emergency services as well as response and recovery. On Kaua'i, the physical impacts were fewer, with a 2 mile stretch of highway damaged by flooding and landslides as compared with 31.1 miles of roads covered by lava on Hawaii island. Both disasters had similar population impacts, with 5,566 people impacted for Kaua'i and 5,563 for Hawai'i. Another difference is a shorter duration of disruption and a quicker restoration of transportation services for Kaua'i compared with the slower, continuous, and permanent loss of transportation services in Hawaii. The two cases provide learning opportunities for emergency managers, transportation planners, and engineers. Both demonstrate the need for redundancy in transportation infrastructure for rescue and recovery operations. While the evacuation from a flooding event is different than from a slower-moving volcanic crisis, the importance of staging areas, route planning, alternative travel modes, and training cannot be overemphasized. These disasters focus attention on the critical role of transportation systems in response and recovery. In addition to short-term operational actions, longer-term mitigation, adaptation, and risk reduction strategies are needed to support transportation resilience.