The paper in Nature Sustainability is available here: http://go.nature.com/2mFdUc4

After a coastal disaster, the decision of where to rebuild often involves a difficult tradeoff. On one hand, rebuilding in-place puts people back in disaster-prone areas. On the other hand, mass relocation projects often have negative impacts on people's livelihoods, land rights, and community cohesion. Facing this tradeoff, the international humanitarian sector typically favors rebuilding in-place. But is this always what people want after a disaster?

Banda Aceh and surroundings after reconstruction. The 2004 tsunami reached ~3 km inland across the low-lying terrain. Following this, the city was rebuilt mostly in-place near the coast.

The 2004 tsunami destroyed half the city of Banda Aceh. Following this, the international reconstruction effort built back mostly in-place near the coast. Examining long-term outcomes, we found that while some tsunami survivors wanted to return, many others preferred to move further inland instead. This caused property prices to increase in areas further from the coast. Tsunami survivors who could afford to move inland have rented out their coastal aid houses to lower-income newcomers to the city. The unintentional consequence has been new socio-economic segregation: wealthier residents tend to live in the inland areas of the city, while poorer residents tend to live in areas exposed to coastal hazards.

Offering a choice  

For future post-disaster reconstruction efforts, these findings suggest that it may be best to offer each household the choice either to return or to relocate to a safer area. In this way, each family can make their own tradeoffs among safety from potential disasters, proximity to their livelihoods, connections to their land and community, and other considerations. In the case of Aceh, the Indonesian government did initially propose such a policy – that survivors had the right to return, but should also be offered the option to relocate further from the coast if they wished to do so. However, this was difficult to implement: the reconstruction agency, local governments, and international NGOs were not able to immediately acquire land in order to offer relocation as an option. For future post-disaster reconstruction efforts, aid providers would need to find ways to overcome these and other challenges in order to offer people a choice in where they rebuild.

Studying disasters and migration

In light of growing coastal populations and rising sea levels, there has been much interest in the influence of disasters, climate change, and other environmental risks on human migration. Studying this poses methodological challenges. Disasters and other risks can have both direct and indirect influences on human migration, while many other factors also influence whether people return or move away.

We designed our study to disentangle these complications. First, we interviewed not only tsunami survivors who moved inland, but also tsunami survivors who returned to the coast. Second, we used open-ended questions to examine people's diverse motivations for moving as well as closed-ended questions to make direct comparisons between those who moved inland and those who returned to the coast. Third, in order to test whether new knowledge of the risk had changed socio-economic patterns in the city, we collected data on property prices, poverty rates, and post-reconstruction urban development. Collecting these data was a substantial team effort among the co-authors and many others who appear in the acknowledgements of the paper.

Research paper

'Socio-economic consequences of post-disaster reconstruction in hazard-exposed areas'

Jamie W. McCaughey, Patrick Daly, Ibnu Mundir, Saiful Mahdi & Anthony Patt

Nature Sustainability 1, 38–43 (2018)
doi:10.1038/s41893-017-0002-z

https://www.nature.com/articles/s41893-017-0002-z