The river corridor is probably the largest area of managed retreat in an urban centre worldwide. How can our experience inform processes of managed retreat elsewhere? The question is central to this project, which has developed a model of ‘retreat’, ‘relocation’ and ‘re-imagining’. Re-imagining asks how can the land be re-used for projects that further lower environmental and social risks.
Ōtākaro Avon Corridor
Over 5,000 homes occupied the Ōtākaro Avon River corridor before the tragic earthquakes of 2010 and 2011. Sitting on poorly consolidated estuarine soils, the shaking from over 14,000 earthquakes caused liquefaction and lateral spread, leading to severe damage to many of these houses.
The land subsided by over 1 meter, and rebuilding those homes would have meant large scale area wide earthworks. In an example of large scale managed retreat, the Crown made the decision to buy the houses in what is has become known as the Ōtākaro Avon River Corridor. The homes were purchased through a process not without controversy, which were then demolished and the land was cleared of all but the major trees and bushes.
At 600 hectares, the river corridor is nearly twice the size of Manhattan's Central Park and four times bigger than Christchurch’s own Hagley Park. It presents a never seen before opportunity for the people of Christchurch. To shape future use of the land, Regenerate Christchurch, a joint Crown-Council agency, was charged with developing the Ōtākaro Avon River Regeneration Plan.
Red zone timelapse. Video by Iain McGregor & Alden Williams
Avonside red zone at sunrise. Image by Iain McGregor & Alden Williams
Based on extensive public consultation and technical investigations between 2016 and 2018, the Plan received government approval in 2019. The Plan sets aside about half the area as a ‘green spine’ either side of the Ōtākaro Avon River, allowing for native forest and wetland regeneration, and facilitating pubic access to the river. The balance of the corridor is intended for projects that are consistent with the objectives of the Plan, including visitor attractions, food resilience, and further ecological restoration (as shown in the map below).
A key objective of this Plan is to establish the area as a Living Laboratory.
The ownership of land has now been transferred to the Christchurch City Council with a process underway to establish an enduring co-governance entity between the community and Ngāi Tūāhuriri.
Reference:
Cloke, P., Conradson, D., Pawson, E., & Perkins, H. (2022). The post-earthquake city: Disaster and recovery in Christchurch, New Zealand (pp. 199-215). Routledge. https://doi.org/10.4324/9780429275562
The Greenprint in detail. By Regenerate Christchurch