EXAMINATION OF EVACUATION PLAN FOR LANDSLIDE TSUNAMI AND SUBDUCTION ZONE EARTHQUAKE TSUNAMI

Abstract

 Since the event of the 2018 Palu tsunami in Indonesia, the countermeasures for reducing tsunami damage have been considered in Palu city where the destructive landslide tsunami event occurred. The tsunami induced by landslide in the Palu bay could reach the coastline of Palu city within a few minutes. On the other hand, there is a possibility that the tsunami induced a subduction-zone earthquake along the Makassar strait could cause the larger inundation area than that of landslide tsunami, although the tsunami could reach the coastline 20 minutes or more after the earthquake.

 In this study, we investigated an effective countermeasure for complex disaster of landslide tsunami occurring in the Palu Bay and anticipated maximum tsunami induced by a subduction-zone earthquake along the Makassar strait in Palu city based on reconstruction plan in the Sulawesi island. We selected the evacuation facilities based on tsunami hazard map of Palu city and assumed the elevated road along the coastline of Palu city to investigate the effect of tsunami damage reduction. As results of evacuation simulation, the elevated road and appropriate selection of evacuation facilities could reduce the mortality rate of the landslide tsunami. Moreover, the importance of establishment of evacuation facilities which could resist against the tsunami induced by the subduction-zone earthquake was implied by the presented examination.