"It is not sustainable to build larger sea defences or levees"

“Legislation for managed retreat will need to consider how to minimise risks to social cohesion, which can be worsened when communities need to relocate,” reads the national adaptation plan. “It must consider unique challenges for low-income groups and mobility-compromised and disabled people when faced with having to shift. One way of doing this is to provide certainty about the process and the opportunities for people and communities to engage.

“The government will work with stakeholders and partners to draw lessons from existing situations of high risk. This will make sure the managed retreat legislation delivers what is needed for councils and communities to deal with issues on the ground. While developing the legislation, the government will consider how current tools can support managed retreat before new legislation (for managed retreat and resource management reform) comes into force.”

While legislation to support managed retreat is yet to be passed, this climate risk response was already previously implemented in New Zealand. Unable to find viable engineering solutions or relevant early warning systems, the regional council for coastal village Matatā chose to pursue a managed retreat in 2012, after properties were either damaged or destroyed by flash floods seven years prior.

In 2014, Oceanian country Kiribati made headlines for purchasing land in Fiji with a view of possibly making it the new home of about 70,000 people in the event of displacement due to rising seas. Last year, however, it was announced that the 5,500-acre property would instead be used for food production after scientists asserted that Kiribati’s sand atolls were not going to disappear.

Read more: South Island floods: Zurich New Zealand extends help even to uninsured

“In the past there was a long tradition of abandonment or managed retreat due to environmental or economic changes, such as drought or a loss of industry,” said Szönyi. “But there may be a need to revive this tradition. It is not sustainable to build larger sea defences or levees along vast stretches of coasts or rivers. Other options will need to be considered. In some cases, managed retreat may even become a necessary response to the impacts of climate change in the decades ahead.”

Citing a 2017 Stanford University study, Zurich noted that approximately 1.3 million people have relocated through managed retreat over the past three decades.

“The need to take conscious decisions about managed retreat will inch closer,” declared Szönyi. “Climate change is already altering the size and direction of migration flows. Instead of people being forced into an unplanned retreat, strategically relocating people through managed retreat may be a better policy. Faced by climate change, our survival depends on changing our ways of life, including where we live.”

Szönyi added that, in certain cases, the managed retreat could be partial and would not have to span entire cities. Additionally, abandoned areas could be turned into wetlands, providing more natural flood spaces while moving people to safety.

Meanwhile, the national adaptation plan states: “Managed retreat is an approach to reduce or eliminate exposure to intolerable risk. It enables people to relocate assets, activities, and sites of cultural significance (to Māori and non-Māori) away from areas at risk from climate change and natural hazards.

“For communities in areas of high risk, managed retreat is an adaptation option. It is usually not considered in isolation from other options, especially when planning for future rather than current impacts of climate change. In some cases, retreat may be a last resort, and in all cases the costs and benefits will need to be carefully weighed.”