With large parts of New Zealand having recently been pummelled by ex-tropical Cyclone Tam and ongoing bouts of heavy rain, it is important to remember that natural hazards have long shaped our cities.
Two townships in particular – Westport and Kume? – have featured in national stories about floods since the 19th century.
They are now among a growing number of places where flooding infrastructure is losing effectiveness and drastic actions have to be considered, including managed retreat.
This raises understandable concerns about anticipated drops in land value and loss of social connection to a place. But managed or planned retreat is not a new concept nationally or globally. International examples can serve as useful references.
These stories from four communities in three countries show how connection to culture and place can be either challenged or sustained when relocation becomes necessary.
Tallangatta, Australia: six decades later
Back in 1956, the Australian township of Tallangatta in north-eastern Victoria was forced to move eight kilometres west because of the expansion of the Hume Weir.
Originally, “old” Tallangatta was located at the meeting point of the Mitta Mitta River and the Tallangatta Creek. But this was subsumed by a significant water-storage facility, the Hume Dam (Lake Hume).
About a hundred houses and a few shops were relocated, including some Victorian buildings. Residents said there was no cost to the relocation, with relocated houses repainted and given modern plumbing facilities that did not previously exist.
The blend of Victorian and mid-century modernist buildings characterises the new township and represents different eras in its history, including the physical and social upheaval of relocation.
But while it can be possible to physically move timber buildings to a new site, characteristics such as original township layout and social connection to the surrounding landscape can be lost.
Mining for iron ore has led to land subsidence, forcing the relocation of the Swedish town of Kiruna.Imgur, CC BY-SA
Kiruna, Sweden: cultural history, industrial growth
Sweden’s northernmost town of Kiruna faces a similar situation due to land subsidence caused by a huge iron ore mine. Its 18,000 inhabitants now have to move about three kilometres east.
The relocation process has not been without its challenges. One big question was how many historic buildings to move to help retain authentic connections to place.
It was proposed that new building design would use the aesthetic qualities of the historic buildings. And there was discussion about either creating an “old town” within the site, or dispersing relocated buildings around the town.
Eventually, local representatives and the mining company (which funded the relocation) decided about 50 of the oldest buildings would be relocated while the remainder would be demolished.
Demolition has now taken place, along with construction of a new town hall to replace its predecessor, a heritage-listed building dating to 1964.
Such decisions call for careful balancing of the impacts on local Indigenous cultural heritage, the economic role the mine has played in the town’s expansion, and its contribution to iron production in Europe in general.
In 2023, the Buller District Council initiated a master plan to guide Westport’s future growth and development. It focuses on the controlled expansion of the township to higher ground on government-owned P?mu farmland one kilometre southwest of Westport.
In the North Island, the township of Kume? is close to Auckland, the country’s biggest city, but still reflects its farming history. Following recent floods, as well as several major floods since 1926, Auckland Council and local leaders joined forces to devise a plan to improve the town’s resilience.
While the prospect of managed retreat has been raised, proactive river maintenance seems the preferred option, including regular debris clearance by local contractors to optimise storm water drainage.
Managed retreat presents opportunities for improvement to Kume?’s infrastructure. But the long-established cultural relationships between people and landscapes in Aotearoa New Zealand also need to inform inclusive decisions about major relocations.
Connection to heritage rests on relationships with place and setting. These can include buildings, landscapes and views, as well as the historical and cultural values associated with a given site.
Stacy Vallis is affiliated with ICOMOS Aotearoa New Zealand, but this article does not represent the views of ICOMOS Aotearoa New Zealand.
Andrew Burgess, Ann Morrison, Imelda Piri, and Priscila Besen do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.
Exclusive: Government and water firms preparing for possible shortages as dry weather is expected to continue
England is heading towards a drought this summer unless there is significant rainfall soon, as reservoir water levels dwindle.
The government will on Wednesday convene the National Drought Group of water companies, farming groups and other experts to prepare for what is expected to be a dry summer with potential water shortages.
Victoria’s conservation regulator has launched an investigation into the suspected fatal poisoning of 300 little corellas in Horsham, in the state’s north-west.
The incident, which began on Tuesday last week, has killed hundreds of protected birds in a popular park near the Wimmera river, just south of the city centre.
Climate change is lengthening fire seasons across much of the world. This means the potential for wildfires at any time of the year, in both hemispheres, is increasing.
That poses a problem. Australia regularly shares firefighting resources with the United States and Canada. But these agreements rest on the principle that when North America needs these personnel and aircraft, Australia doesn’t, and vice versa. Climate change means this assumption no longer holds.
But to what extent do fire seasons in Australia and North America actually overlap? Our new research examined this question. We found an alarming increase in the overlap of the fire seasons, suggesting both regions must invest far more in their own permanent firefighting capacity.
What we did
We investigated fire weather seasons – that is, the times of the year when atmospheric conditions such as temperature, humidity, rainfall and wind speed are conducive to fire.
The central question we asked was: how many days each year do fire weather seasons in Australia and North America overlap?
To determine this, we calculated the length of the fire weather seasons in the two regions in each year, and the number of days when the seasons occur at the same time. We then analysed reconstructed historical weather data to assess fire-season overlap for the past 45 years. We also analysed climate model data to assess changes out to the end of this century.
And the result? On average, fire weather occurs in both regions simultaneously for about seven weeks each year. The greatest risk of overlap occurs in the Australian spring – when Australia’s season is beginning and North America’s is ending.
The overlap has increased by an average of about one day per year since 1979. This might not sound like much. But it translates to nearly a month of extra overlap compared to the 1980s and 1990s.
The increase is driven by eastern Australia, where the fire weather season has lengthened at nearly twice the rate of western North America. More research is needed to determine why this is happening.
Longer, hotter, drier
Alarmingly, as climate change worsens and the atmosphere dries and heats, the overlap is projected to increase.
The extent of the overlap varied depending on which of the four climate models we used. Assuming an emissions scenario where global greenhouse gas emissions begin to stabilise, the models projected an increase in the overlap of between four and 29 days a year.
What’s behind these differences? We think it’s rainfall. The models project quite different rainfall trends over Australia. Those projecting a dry future also project large increases in overlapping fire weather. What happens to ours and North America’s rainfall in the future will have a large bearing on how fire seasons might change.
While climate change will dominate the trend towards longer overlapping fire seasons, El Niño and La Niña may also play a role.
These climate drivers involve fluctuations every few years in sea surface temperature and air pressure in part of the Pacific Ocean. An El Niño event is associated with a higher risk of fire in Australia. A La Niña makes longer fire weather seasons more likely in North America.
There’s another complication. When an El Niño occurs in the Central Pacific region, this increases the chance of overlap in fire seasons of North America and Australia. We think that’s because this type of El Niño is especially associated with dry conditions in Australia’s southeast, which can fuel fires.
But how El Niño and La Niña will affect fire weather in future is unclear. What’s abundantly clear is that global warming will lead to more overlap in fire seasons between Australia and North America – and changes in Australia’s climate are largely driving this trend.
Looking ahead
Firefighters and their aircraft are likely to keep crossing the Pacific during fire emergencies.
But it’s not difficult to imagine, for example, simultaneous fires occurring in multiple Australian states during spring, before any scheduled arrival of aircraft from the US or Canada. If North America is experiencing late fires that year and cannot spare resources, Australia’s capabilities may be exceeded.
Fire agencies are becoming increasingly aware of this clash. And a royal commission after the 2019–20 Black Summer fires recommended Australia develop its own fleet of firefighting aircraft.
Long, severe fire seasons such as Black Summer prompted an expansion of Australia’s permanent aerial firefighting fleet, but more is needed.
As climate change accelerates, proactive fire management, such as prescribed burning, is also important to reduce the risk of uncontrolled fire outbreaks.
Doug Richardson receives funding from the ARC Centre of Excellence for Climate Extremes (CE170100023) and the Germany-Australia Joint Research Cooperation Scheme, funded by the Deutscher Akademischer Austauschdienst (DAAD) and Universities Australia (RG230014)
Andreia Filipa Silva Ribeiro receives funding from the Deutsche Forschungsgemeinschaft (DFG) – Project number 530175554, the Alexander von Humboldt Foundation (AvH) and the Germany-Australia Joint Research Cooperation Scheme, funded by the Deutscher Akademischer Austauschdienst (DAAD) and Universities Australia (RG230014).
The mass mortality event that hit Tasmania’s salmon industry has ended, the state’s environmental watchdog says, as industry reporting shows fish deaths in March halved from the previous month.
