Measures to protect cities from the intense storms and rising sea levels caused by climate change should consider projects which also enhance life in the city, visiting expert Kai-Uwe Bergmann says.
Extreme weather such as Hurricane Florence, which has just engulfed parts of the US eastern seaboard, will become more frequent and architects and engineers face the challenge of how to design cities and buildings that can cope with flooding and storms.
Bergmann is a partner at BIG, a global network of experts in this field, and he's in New Zealand to discuss his work in resiliency.
He says BIG has been working on several cities - including New York and San Francisco in the US and various cities across Europe - to figure out how those cities, and the people who live in them, can adapt to climate change.
"We call this social infrastructure, creating the infrastructure that will protect the city but never losing mind of how people will actually use the city and how the investments in infrastructure can actually support city life."
He says superstorm Sandy exposed and corroded the New York subway cabling so much that the ‘L’ train is still out of action.
“The subway is over 100 years old and it was the first time in 100 years that the subway actually flooded, so you can tell the scope and scale of the storm - $20 billion of damage."
To protect against similar flooding in the future, BIG has designed "the big U".
"It’s shaped like a U around the tip of Manhattan. The idea is to actually create a berm which goes up to about 15 or 16 feet [4.5m to 4.9m] that will protect the city over the next 100 years of sea level rise."
The berm will protect the city and create a park, he says. The project will cost between US$3 billion and $4 billion and provide 16 kilometers of protection.
"It’s the largest investment in creating green space and open space for the city since Central Park."
He says there are other examples: The Netherlands, which has fought against flooding for centuries is looking at embracing the inundation of its land, Venice is looking at installing a gate system called MOSE they're not sure will work, and Indonesia is also exploring protecting its capital which is under threat from sinking tectonic plates as well as rising sea levels.
"Indonesia, which suffers a lot of flooding also is considering flood gates at the mouth of the bay to the tune of about $7bn," Bergmann says.
He says the difference between the Indonesian and New York approaches is Indonesia's flood protection only provides protection during one in a 100-year storms.
"What we're looking at in New York is how can you invest those billions of dollars of investment and create something that people will be able to enjoy every single day.
Another project in which he's involved is amphibious accommodation. The idea is to create student housing in Copenhagen made from shipping containers that can float.
"Student housing which is lacking in the city of Copenhagen, and using shipping containers - recycling them and basically placing a student in every shipping container. You have a wonderful bedroom right on the water for one third of the price of a normal dorm room."
He says there are lots of ways New Zealand can also learn from overseas.
"Japan is also a great example of how to build with or for earthquakes and I think that we can learn a lot from one another - from the Dutch, from the Japanese - and sharing these experiences with one another is key to dealing with the future.
"I think one of the things that I’ve also noticed in driving around Wellington is the sort of adaptive seismic work that’s happening where you have buildings on spindly legs getting a steel truss wrapped around them I think in a very elegant way."
Small regional towns close to the shore need a combination of tools to manage the sea level rise, he says.
"Retreat is actually a very important aspect, you have also the storage of certain water, you can resist which is placing a floodwall in front of those homes and resisting mother nature, but I think mother nature has proven that she usually wins."
He says that applies in the case of Haumoana, where 21 homes are under threat from the rising sea level.
"I think it’s creating an intelligent narrative and argument for those 21 home owners to understand that there are moments to resist, there are moments to store and there are moments to retreat.
"It’s probably a combination of all of those things - there’s no single answer in any situation: how you deal with these climatic issues is actually creating an array of tools."
Kai-Uwe Bergman is in New Zealand to headline the Construction Marketing Services design experience series and will speak in Wellington, Tauranga and Auckland on 25, 26 and 27 September.