Analysis and Geovisualization of Tsunami Hazard and Evacuation Routes in the Opak-Progo Coastal Area

The southern coastal area of Java has a high risk of tsunamis. Additionally, the presence of rivers flowing in the south of Java Island poses a greater tsunami threat because these rivers can act as "toll roads" for tsunami waves to enter the land. Therefore, this study was conducted in the coastal area of the Opak-Progo watershed to determine the level of tsunami hazards and plan effective evacuation routes. The hazard map was created using the Berryman method, which employs parameters such as slope, surface roughness coefficient, coast-line, and tsunami run-up height scenario; a 3-metre scenario was used in this study. Network analysts also determined evacuation routes using the nearest facility method. Network analysis was used to identify an optimised route with four evacuation sites. This research has the potential to significantly contribute to tsunami mitigation and evacuation planning in the coastal areas of the Opak-Progo watershed.