Tsunami evacuation buildings and evacuation planning in Banda Aceh, Indonesia.

Indonesia, a country of more than 17,000 islands, is exposed to many hazards. A magnitude 9.1 earthquake struck off the coast of Sumatra, Indonesia, on December 26, 2004. It triggered a series of tsunami waves that spread across the Indian Ocean causing damage in 11 countries. Banda Aceh, the capital city of Aceh Province, was among the most damaged. More than 31,000 people were killed. At the time, there were no early warning systems nor evacuation buildings that could provide safe refuge for residents. Since then, four tsunami evacuation buildings (TEBs) have been constructed in the Meuraxa subdistrict of Banda Aceh. Based on analysis of evacuation routes and travel times, the capacity of existing TEBs is examined. Existing TEBs would not be able to shelter all of the at-risk population. In this study, additional buildings and locations for TEBs are proposed and residents are assigned to the closest TEBs. While TEBs may be part of a larger system of tsunami mitigation efforts, other strategies and approaches need to be considered. In addition to TEBs, robust detection, warning and alert systems, land use planning, training, exercises, and other preparedness strategies are essential to tsunami risk reduction.