The eye-opening discovery that some of the worst-damaged houses in Auckland weren't on the coast, but were high on the hills, gives weight to a new report on compensating managed retreat from climate change. Jonathan Milne reports.
Around 100 households in West End Ōhope and more on Ōhiwa sand spit were evacuated overnight, before high tide hit their low-lying homes at 1.30 this morning. Earlier flooding had already left one house teetering spectacularly on the brink.
The danger of flooding would have come as little surprise – for more than a decade now, their district councils have been setting tight rules around building along the coastline.
The 19th century Ferry Hotel and nearby Ōhiwa Post Office were lost to erosion in 1915. Then in the 1970s, more houses were lost to the sea. Others were abandoned. Some of the titles were converted to public ownership, in exchange for alternative land elsewhere.
More recently, a landowner wanting to build a house on Ōhiwa Spit was told the dwelling had to be constructed out of timber on driven piles, with the identification of an erosion trigger point 30 metres from the boundary – and a plan for removal within three days of the trigger being breached.
To the people of Ōhope, Ōhiwa and of course neighbouring Matatā, arguments around managed retreat – and who should pay for it – are nothing new.
READ MORE: * Big premiums hikes as climate adaptation plan identifies need for insurance * Longterm leases to ease pain of forced climate retreat * Managed retreat from the 'parasitic' creep of climate change * Matatā: The town that had to retreat
Further west along the coast in fast-growing, low-lying Papamoa, too, developers are required to provide and maintain an alternative vacant building site for future relocation.
But the Auckland floods of the past few weeks have revealed something more. The people of Auckland, and of New Zealand, have learned that managed retreat from climate change will be a consideration and a cost for many hundreds of thousands of us. Not just those who built on the coast.
Children splashing, kite-surfers catching the breeze – in the days after the January 27 floods, Aucklanders discovered a new lake high up on the Domain, by the War Memorial Museum.
Its waters may have been contaminated, but they were less of a threat than the many other floods that surprised home and business owners who thought they were elevated above any risk.
The flash-flooded lakes at the Domain, and Parnell, and throughout Remuera and Greenlane and Epsom, were entirely predictable to anyone who had inspected Auckland Council's GeoMaps, and discovered the many blue splotches of flood plains across the city.
"We are living in a climate changing world. This was highlighted very vividly on January 27 this year when Auckland experienced its wettest day on record, by far, with more than 260 millimetres of rain falling in parts of the city." – 'Principles and Funding for Managed Retreat'
These are high above sea level. There are areas on many of the city's maunga – public amenities like the band rotunda and cafe on One Tree Hill, as well as many homes and businesses – that are built on flood plains or waterways.
Indeed, the houses that were damaged worst in the January 27 floods were not inundated by the rising tides, but were undermined or crushed by torrents of water and rocks from above.
A new report, "Principles and Funding for Managed Retreat", lays out the options for moving out of the flood zones – and how we as communities might pay for it. Managed retreat is variously referred to as ‘planned relocation’, ‘planned resettlement’, ‘community-led relocation’ or ‘phased abandonment’ – alarming turns of phrase, in each case, and almost certainly costly.
Authors Raewyn Peart, Emeritus Professor Jonathan Boston, Sasha Maher and Teresa Konlechner reach one emphatic conclusion: the Government will need to intervene and help bankroll a public compensation scheme.
"We are living in a climate changing world," the report says.
This was highlighted very vividly on January 27, the report says, when Auckland experienced its wettest day on record by far, with more than 260 millimetres of rain falling in parts of the city.
"An entire summer’s rain fell in one day. There was extensive flooding of homes, businesses and roads. Numerous cars become stranded in the floodwaters. Land slips moved homes off their foundations and left others teetering on the edge.
"The domestic and international terminals at Auckland International Airport flooded bringing the airport to a standstill and stranding more than 2,000 travellers in the flooded buildings. Tragically, four people lost their lives. The clean-up will be extensive with more than 1,000 properties in Auckland red or yellow stickered. Insurance claims are predicted to hit nearly $1 billion."
The report, commissioned by the Environmental Defence Society, lays out a wider scope for compensation than that previously contemplated by the Government and its officials. Business, big and small, would likely be compensated alongside private residents, it argues.
And it's not necessarily coastal communities. By far the largest example of managed retreat in the country occured in Christchurch following the 2010-11 earthquakes. Red-zoning affected close to 8,000 properties; more than 20,000 people were relocated.
"Managed retreat will likely be costly, complex and controversial. Many residents and communities in vulnerable locations will be reluctant to relocate, not least because of limited financial means and strong attachments to place." – Environmental Defence Society report
The cumulative impacts of climate change mean that major flooding, mud flow and coastal erosion events will increase in frequency and intensity. The country is particularly vulnerable due to most major cities, as well as numerous towns and other settlements, being built on floodplains or on the coast.
A one-in-100 year flood could affect close to 20,000 sq km of land and more than 675,000 people and 400,000 buildings. Also at risk are some 20 airports, including the Auckland and Christchurch international airports; major industrial developments such as the Tiwai Point Aluminium smelter, Marsden Point Oil Terminal and Taranaki Methanex methanol production facilities; and major roads, railway lines and electricity transmission lines.
"Managed retreat will likely be costly, complex and controversial. Many residents and communities in vulnerable locations will be reluctant to relocate, not least because of limited financial means and strong attachments to place. However, relocating people prior to damage occurring is likely to be financially cheaper, less risky, less disruptive and less socially harmful than relocating people following a major damaging event....
"Costs should be significantly reduced in the longer term if a well-designed, well-funded and well-managed approach is implemented by government in a timely manner."
Jonathan Boston facilitated two workshops on managed retreat, as part of the Ministry for the Environment's consultation on the Government's National Adaptation Plan last year.
So the report is informed by the work he has done for government, and it is supported by an additional paper he has written on funding managed retreat.
Quoting NIWA's recent climate change projections, it says extreme weather events will become more frequent and intense, and there will be large increases in extreme rainfall. "Such changes in the climate are placing more and more humans and other species in harm’s way," it says. "The 2020 National Climate Change Risk Assessment highlighted the significant risks to social cohesion and community wellbeing from the displacement of individuals, families and communities due to climate change impacts."
It says Māori are particularly susceptible to a climate changing world, because they are unwilling to break their strong connections with landmarks such as maunga and awa. "They maintain their connection with place through activities such as visiting their marae or swimming in their awa. The loss of such places can undermine a sense of identity as well as threaten the health and wellbeing of Māori communities."
In 2020, the Government proposed a Climate Adaptation Act to address complex issues such as funding, compensation, land acquisition, liability and insurance. Other laws, like the new Natural and Built Environment Act and Spatial Planning Act, and the existing Public Works Act, are seen as inadequate to move people and infrastructure out of harm’s way.
"In some highly exposed areas, the risk from natural hazard and climate impacts may become intolerable. Inundation of buildings and infrastructure will start to occur, leading to direct damage and loss of some facilities like roads or other lifeline services, and public open space." – Ministry for the Environment
The new law is intended to be introduced to Parliament by the end of 2023. In the words of the Ministry for the Environment, managed retreat is an approach to reduce or eliminate exposure to "intolerable risk".
It warns that even in areas where communities are safe, local services and infrastructure such as roads, power lines and pipes may become damaged more frequently and be more expensive to maintain because of erosion or increases in storms and rainfall, for example. Local councils may decide to stop maintaining these services.
"In some highly exposed areas, the risk from natural hazard and climate impacts may become intolerable," its consultation paper says. "Inundation of buildings and infrastructure will start to occur, leading to direct damage and loss of some facilities like roads or other lifeline services, and public open space. In some cases, the risks may reach a threshold where relocation will need to be considered."
It is not always obvious that an area is at high risk from natural hazards or the impacts of climate change, the consultation paper says. However, council risk assessments and increased data and information should make these risks clearer.
"When private insurance becomes unavailable, it does not make sense for the Government to step in to become an insurer of an uninsurable risk ... Auckland Council recommends support is offered through risk reduction and managed retreat." – Auckland Council
Some submitters, like Auckland Council, have warned against providing government-underwritten insurance (like the UK's Flood Re scheme) that might be a disincentive to home-owners to take responsibility. They note that avoiding moral hazard should be a key consideration when deciding who to provide insurance to, and how.
Auckland Council says a compensation scheme should be needed only for property owners who were unaware of the risk to their homes at time of purchase; instead, Government should work to reduce risk.
"When private insurance becomes unavailable, it does not make sense for the Government to step in to become an insurer of an uninsurable risk," it says. "Therefore, Auckland Council recommends support is offered through risk reduction and managed retreat."
In the consultation on the managed retreat scheme, the Ministry for the Environment asked how any state-underwritten insurance should be paid for. Most submitters wanted it funded out of existing taxes, rather than a targeted levy on property owners, or some other kind of government support – but there was little agreement.
Other suggestions included using the Emissions Trading Scheme to fund insurance; using a means-tested sliding scale; council restrictions on new developments; central government collaborating with insurers to underwrite flood insurance; and central government, council, and insurer support for the cost of funding insurance in high-risk areas.
Some submitters said that if communities had to be relocated, the whole community should be considered including facilities like schools, churches and marae, and the businesses needed for that community to thrive. But others argued that businesses may have greater options and resources for relocation than homes or community buildings, and should be able to look after themselves.
Other managed retreats in NZ
Matatā and Ōhiwa Spit may be well-known examples of managed retreat in New Zealand, but other communities have been unable to agree on managed retreat as part of a wider process of adaptation. These include the Hawke's Bay coastal settlement of Haumoana, the coastal settlement of Mākara, in Wellington,5 the small riverine settlements of Waitōtara and Whangaehu, and a riverside suburb in Whanganui. And as a 2006 Environment Waikato report documents, there are other communities that have been grappling with the problem for many years:
Muriwai Beach, Auckland: A major emergency operation was under way in Muriwai, 42km northwest of Auckland, after two firefighters were caught in a landslide early on Tuesday, February 14, investigating flooding caused by Cyclone Gabrielle.
One of Auckland’s most popular regional park beaches with more than 840,000 visits per year, it's long been susceptible to land sliding away into the sea. The beach is currently undergoing erosion at rates of 1-1.5 metres per year, possibly of a long-term nature. Erosion is affecting a variety of public recreational assets. Initial attempts at protection work failed.
In 2004, the council adopted a recommendation to accommodate coastal erosion by a gradual process of retreat – possibly the only New Zealand example of the implementation of a deliberate formal strategy of retreat. Mainly public park assets and open spaces remain at risk.
Westport, West Coast: The Westport community is facing significant challenges in adapting to the effects of flooding and climate change, the Ministry for the Environment says. Severe floods in July 2021 and February 2022 caused widespread damage to homes and infrastructure, and the Buller District Council required central government funding to help with the recovery.
The July 2021 event was the largest direct measurement of a river flow ever recorded in Aotearoa. It flooded more tha 400 houses, incurred insurance costs of around $56m, and made it necessary to create a temporary housing area for those who could not return to their homes.
An important adaptation action is investing more in flood risk reduction; every $1 invested in flood protection schemes results in a $6 return on investment, the ministry argues. But local ability to fund adaptation and flood protection is likely to be a challenge, as many among the population have very low incomes. Central government is partnering with local councils and iwi to explore new funding and financing models for co-investing in climate adaptation for Westport.
Mokau Spit, Waitomo: Forty six sections were offered for sale at Mokau Spit in September 1957 and, from the earliest days, letters from property owners identified problems with erosion. By 1962 it was severe and damaging some properties. Eleven sections were revested in the Crown, either by surrender of licences or leases or a transfer of properties. The former Department of Lands and Survey made payments to the owners – a full refund for the original purchasers, and 50 percent for subsequent owners.
Twelve sections have been lost to the sea. Erosion has been severe in the past 10 years and protection works have been attempted and failed. In at least two cases, owners have moved the houses further inland on their sections after the difficulties with protection became evident. In other cases, owners have persisted with attempting unauthorised protection works.
Pourewa Point, Aotea Harbour: The settlement at Pourewa Point is located near the entrance to Waikato's Aotea Harbour. Shoreline erosion between 1963 and 1995 resulted in the complete loss of up to 22 private sections, and the partial loss of another 12. Significant areas of reserve were also lost.
A number of properties were abandoned during the 1970s, with the owners often buying other local sections, which were relatively cheap compared to other coastal holiday settlements. Other property owners have attempted to mitigate erosion with shoreline armouring measures, which are now in a state of disrepair. Local iwi are concerned about the adverse impacts on coastal values.
Te Kopi, Wairarapa: Property owners at Te Kopi village, on the seaward side of the main road to Cape Palliser, attempted a variety of protection works but these failed and both properties and baches were lost to the sea.
The style of baches and value of properties was relatively modest compared with those on east coast of Auckland, Waikato and Bay of Plenty Regions, the Environment Waikato report notes. Twenty years ago, resource consent was granted to build a boulder beach protection work to protect the main road, which provides a strategically important connection to other parts of the district.
Waihi Beach, Bay of Plenty: Waihi Beach has a history of episodic erosion and storm surge events.
Some residential buildings were voluntarily relocated in response to coastal hazard events early in the history of the Waihi Beach subdivisions. However, the majority of affected residents opted for protection works.
Wainui Beach, Gisborne: Two buildings were voluntarily relocated from Pare St on Wainui Beach, which is subject to long-term episodic erosion.
However, the majority of property owners opted for protection works.