Sign up

Managed retreat from areas threatened by floods can catalyse positive social transformations

Hundreds of millions of people will be affected by coastal flooding in the coming decades. Rather than being a 'last resort', managed retreat from threatened areas can be an effective way to create broader social transformations, according to the latest knowledge brief from the Transformations to Sustainability programme.

This article is part of the ISC’s Transform21 series, which features resources from our network of scientists and change-makers to help inform the urgent transformations needed to achieve climate and biodiversity goals.

Recent weeks have seen unanticipated, catastrophic flooding on the east coast of Australia. There have been several other highly mediatized floods over the past year, such as in the UK, Germany and New York, but less visible floods occur almost constantly around the world, most recently in Mozambique, Brazil and Indonesia.

The latest report of the Intergovernmental Panel on Climate Change (IPCC) Working Group II, published in February, tells us with ‘high confidence’ that ‘recent heavy rainfall events that led to catastrophic flooding were made more likely by anthropogenic climate change’. The threat from extreme events, including flooding, is certain to intensify in coming years as a result of climate change. Inhabitants of coastal regions are among those most at risk from flooding due to rising sea levels caused by climate change.

In light of this trend, we must stop thinking of managed retreat – that is, planned relocation and resettlement – from areas prone to coastal flooding as an option of last resort and accept that it must quickly become a standard, first-line climate adaptation strategy. Research suggests that, over the next 80 years, up to 630 million people are likely to be affected by coastal flooding and sea-level rise. More than 300m people will be living below projected annual flood levels by mid-century. The majority of those at risk live in the densely populated coastal cities of developing countries in Asia, but all regions of the world are vulnerable. In some Small Island Developing States, entire islands are at risk of becoming uninhabitable.

Some of the reasons that we do not easily entertain the option of retreat are psychological and cultural. The idea of retreat is often emotionally and politically highly charged. Culturally it has been associated with notions of loss, defeat and the failure of costly engineering solutions. However, managed retreat has been successfully practiced for centuries in different parts of the world, and a growing body of research is showing that managed retreat today can not only provide a practical solution to a very concrete physical problem, it can also contribute to positive wider transformations towards greater equity and environmental sustainability. A recent knowledge brief from the ISC’s Transformations to Sustainability programme illuminates some of the factors that determine how managed retreat can lead to positive social transformations.

Managed retreat diagram

The transformative potential of managed retreat in the face of rising sea levels

Nothing makes the realities of climate change more concrete and immediate for communities than the prospect of having to retreat from vulnerable areas. People’s attachment to place and community is so natural that they can readily empathize with those who are concerned by the need to relocate. Conversations around retreat (Who retreats? To where? In what way? Who decides and manages the process?) help to transform social perceptions, narratives and norms related to adaptation to climate change, particularly in relation to the role historic injustice has played in determining who is most at risk from climate change and adaptation strategies. The need to ‘surrender’ to nature may also have the positive effect of helping to change societies’ attitude to nature – from one of dominance and exploitation to one of co-existence and respect.

Whether or not retreat generates a positive, broader change over the longer term appears to be closely linked to who is involved in conversations and decisions about retreat. Research on diverse cases, including the Mekong Delta in Vietnam, waterfront areas of Lagos, and Staten Island in New York, indicates that the inclusivity of decision-making around relocation is one of the key factors that determine whether or not a retreat can lead to broader positive transformations, largely because this affects the likelihood that a retreat will contribute to greater social equity and protect ecosystems over the short and long term. The successful community-led voluntary retreat in Caño Martín Peña in Puerto Rico involved residents throughout the planning and implementation process, and the mental health of residents was also prioritized throughout the move, with the provision of psychosocial support.

At worst, resettlement can undermine the agency of people affected and reduce the resilience of a community, or just shift risk from one area to another. One study of financial incentives offered for relocation away from Staten Island after Hurricane Sandy found that that 20% of participants relocated to floodplains with an equal or greater risk of flooding, and 98% moved to areas with higher poverty rates. Research from the Philippines has indicated that pre-existing inequalities in wealth and power tended to contribute to unequal outcomes after a managed retreat, even when planning processes are robust.

As the recent report from the IPCC  highlights, there is increased evidence of ‘maladaption’, or responses to climate change that exacerbate existing inequalities and can create lasting vulnerabilities that are difficult to reverse. In order to avoid maladaption with managed retreat, flexible, multi-sector and inclusive planning is essential.

Synthesis of multiple studies shows that managed retreat is more likely to be beneficial when it is pursued as a means to achieve broader transformation and as an opportunity to disrupt and redress systemic injustices. This requires stakeholders in the process to explicitly address a wide range of justice issues, including distributive and procedural justice as well as recognition and restorative justice. Policy-makers must ensure that the people affected by managed retreat, from both origin and host communities, are fully involved in the planning process. Managed retreat should also be situated within larger, holistic efforts to address inequities in economic development, land use patterns, environmental protection and community wellbeing.

The scale of the climate emergency means that relocation on a massive scale is now inevitable. The humanitarian, environmental and geopolitical implications of large-scale relocation are enormous. Unmanaged and ‘last-resort’ retreat will create new vulnerabilities and costs, as well as being a missed opportunity to promote sustainability. How best to manage retreat is therefore a pressing question for researchers, communities and policy-makers worldwide. Decision-makers must anticipate the looming crisis and start having serious conversations about managed retreat for vulnerable communities now.

Image by Vince Basile via Flickr.

Skip to content