Managed retreat and experimentation: realising opportunity in the Ōtautahi Christchurch residential red zone, Aotearoa New Zealand

Figures & data

Table 1. Examples of managed retreat situations in Aotearoa, 2024.

Auckland

Cause: Floods, 27 January to 1 February; followed by onshore floods, landslides due to Cyclone Gabrielle, 13–14 February 2023

Description: 700 category 3 properties where risk to life cannot be mitigated

Resolution: property buyouts based on 50/50 cost sharing council/Crown; almost $2 billion cost share agreement also covers roads, bridges and flood protection

Sources: media and https://www.aucklandcouncil.govt.nz/recovery-extreme-weather-disasters/property-categorisation-resolution/Pages/category-3-property-buyout-information-auckland-council-government.aspx

Bay of Plenty: Matatā and Maketu

Cause: Matatā debris flow in 2005; Maketu anticipatory planning in face of storm events and sea level rise

Description: 27 homes destroyed, 87 damaged in Matatā

Resolution: messy, prolonged in Matatā; iwi-led, community plan in Maketu including provision for retreat based on tikanga Māori

Sources: media, Hanna C, White I, Glavovic B. (2018); https://maketuclimateplan.iwi.nz/wp-content/uploads/2023/11/Maketu-Climate-Change-Adaptation-Plan-He-Toka-Tu-Moana-Mo-Maketu.pdf

Hawkes Bay

Cause: onshore floods, landslides caused by Cyclone Gabrielle, 13–14 February 2023

Description: 287 category 3 properties

Resolution: property buyouts based on 50/50 cost council/Crown; $556 million cost share agreement also covers roads, bridges and flood protection

Sources: media and https://www.hbrc.govt.nz/assets/Document-Library/Fact-Sheets/Negotiatedfundingoutcomes-factsheet-V03.pdf

Kapiti coast

Cause: an urbanised coast and inlets at risk of coastal flooding long term

Description: anticipatory action to identify hundreds of properties at risk heavily resisted ten years ago; ongoing resistance

Resolution: community and iwi engagement in coastal adaptation plan development

Sources: media and https://www.takutaikapiti.nz

Westport

Cause: recurrent coastal and river flooding, July 2021, February 2022

Description: 2000 evacuees in these events

Resolution: Crown funding for flood wall; council funded infrastructure for 700 homes on higher ground; no funding for individuals

Sources: media and https://bullerdc.govt.nz/your-council/key-projects/resilient-westport-package/

Franz Josef

Cause: extreme flooding risk from Waiho river, confined by stopbanks but 15 metres above land either side

Description: infrastructure at risk, plus farmland to the south and the tourist township of 500 people, with 700 000 annual visitors, to the north

Resolution: recommendation to remove stopbanks on the south side to relieve pressure on those on the north side; funding unresolved

Sources: media and Beagley R, Gardner M. (2023).

South Dunedin

Cause: low-lying suburb subject to rising groundwater levels

Description: houses and streets vulnerable to heavy rainfall and rising sea level

Resolution: anticipatory South Dunedin Future Programme between city and regional councils: 100-year adaptation plan including property buyouts properties to facilitate nature-based solutions

Sources: media and https://www.dunedin.govt.nz/__data/assets/pdf_file/0014/1021505/sdf-context-summary-report.pdf

Christchurch

Cause: seismic movement during the Canterbury earthquake sequence, 2010–2013; ground deformation due to liquefaction and subsidence equivalent to decades of sea level rise

Description: substantial coastal, flood plain and some hill districts red zoned in 2011, 8000 households affected

Resolution: households incentivised to move with Crown buyouts, at cost of over a billion dollars

Sources: Regenerate Christchurch (2019); Cloke P, Conradson D, Pawson E, Perkins HC. (2023)

Figure 1. Ōtautahi Christchurch red zones.

Figure 2. ‘From red zone to green zone’: incipient wetland after heavy rainfall in red zoned Bexley, October 2021. Photograph: Eric Pawson.

Figure 3. Abandoned red zoned street in Avonside, October 2018. Photograph: Eric Pawson.

Figure 4. Ōtākaro Avon River Corridor development plan, showing edge and trial housing areas. Source: Christchurch City Council.

Hanna C, White I, Glavovic B. 2018. Managed retreat governance: insights from matatā, New Zealand. Report for the National Science Challenge: Resilience to Nature's Challenges. Hamilton: University of Waikato.

 Google Scholar

Beagley R, Gardner M. 2023. Waiho River. Historic and future management strategies. Christchurch: Land River Sea Consulting.

 Google Scholar

Regenerate Christchurch. 2019. Ōtākaro Avon River Corridor Regeneration Plan. Christchurch: Regenerate Christchurch.

 Google Scholar

Cloke P, Conradson D, Pawson E, Perkins HC. 2023. The post-earthquake city. Disaster and recovery in Christchurch, New Zealand. Abingdon: Routledge.

 Google Scholar