Planning of Tsunami Evacuation Sites and Routes Based on a Megathrust Scenario to Support the Tsunami Ready Program: A Case Study of Pengambengan Village, Indonesia

Pengambengan Village, located in Jembrana Regency, is highly susceptible to tsunami disasters, necessitating the implementation of mitigation measures through the Tsunami Ready Program. This study aims to develop a tsunami hazard map and identify tsunami evacuation sites and route scenarios in Pengambengan Village to meet the Tsunami Ready indicators. The tsunami hazard map was generated by tsunami modeling based on a worst-case scenario on the Sumba Megathrust segment with Mw 8.5 using the COMCOT and QGIS software. Recommended evacuation sites and routes were determined through network analysis using GIS-based network analysis. The tsunami modeling results indicate that approximately 91.7 percent of the area in Pengambengan Village is affected by tsunamis, with maximum flow depths ranging from 6 to 10 meters in Banjar Ketapang Muara and Banjar Kombanding. The estimated tsunami arrival time near Pengambengan Beach is approximately 37 minutes, with maximum tsunami inundation extending up to 1.6 kilometers. The service area analysis identified four potential tsunami evacuation sites in Pengambengan Village. However, Banjar Ketapang Muara remains inadequately covered due to a lack of suitable evacuation sites and buildings. This study determined seven optimal evacuation routes to the proposed tsunami evacuation sites. Additionally, the findings suggest constructing a vertical evacuation site in Banjar Ketapang Muara to address the identified gap. The outcomes of this study contribute to supporting the Tsunami Ready Program in Pengambengan Village.