Evaluating Infrastructure for Tsunami Evacuation in Padang, West Sumatra, Indonesia
GHI’s project promoting tsunami preparedness in Sumatra, with partners Geoscientists Without Borders and Stanford University’s Engineers for a Sustainable World, completed its field work in Summer 2009, when project manager Veronica Cedillos traveled with Stanford student interns Scott Henderson, Nick Jachowski and Kelly Wood to Padang, West Sumatra. The team spent close to two months in and around Padang, carrying out site and feasibility studies to support the project’s evacuation infrastructure planning.
Padang, the most populated city in West Sumatra, is considered to have one of the highest tsunami risks in the world due to its high hazard, vulnerable terrain and population density. Currently, the strategy to prepare for a tsunami in Padang is focused on developing early warning systems, planning evacuation routes, conducting evacuation drills, and educating the public of its tsunami risk. Although these are all necessary efforts, they are not sufficient. It is estimated that roughly 50,000 inhabitants of Padang will be unable to evacuate in the time between a strong earthquake and the resulting tsunami, even if they head for safe ground immediately after the earthquake. For these reasons, it’s crucial to develop other means to prepare for the expected tsunami.
The field visit enabled the team to explore in much greater depth potential tsunami evacuation strategies, which include: retrofitting existing structures, designing new evacuation structures with alternate meantime uses, investigating the seismic integrity of existing bridges, and researching the earthquake and tsunami parameters required for safe engineering design. The team also met with local stakeholders and with other organizations studying tsunami and earthquake risk in the region, in order to identify any “gaps” in the city’s current evacuation planning, where GHI and its project partners could most beneficially contribute expertise.
Based on its field investigations and on instructive dialogues with Indonesian organizations that include Andalas University in Padang, Laboratory for Earth Hazards (LIPI), and the Ministry of Marine Affairs and Fisheries (DKP), the team concluded that:
- tsunami evacuation structures and bridges are essential to protect the inhabitants of Padang;
- there is a need for a more thorough, engineering-based evaluation than has been conducted to-date of the suitability of existing buildings to serve as evacuation structures, and of existing bridges to serve as elements of evacuation routes, and;
- additions to Padang’s tsunami evacuation infrastructure must carefully take into account technical matters, social considerations, and political issues specific to Padang.
Future plans include collaboration between U.S. and Indonesian engineers in developing designs for tsunami evacuation structures, as well as providing training for Indonesian authorities on siting, designing, and constructing tsunami evacuation structures, and; evaluating the suitability of buildings to serve as tsunami evacuation shelters.