Future Proof: Envisioning Asian Cities In A Climate Change-Impacted World
Jakarta has always been prone to floods, but this was something else entirely. On the first day of this year, the Indonesian capital was inundated by nearly half a metre of rain. Two rivers overflowed their banks. Drains couldn’t handle the downpour and flash floods ripped through the city. Sixty-six people were killed and 60,000 were displaced from their homes.
The following month, Indonesia’s Meteorology, Climatology and Geophysics Agency made a declaration: the floods were caused by climate change. “In addition to the increase of rainfall intensity and the continuation of extreme conditions, it turns out that the temperature of Indonesia has also significantly increased,” said the agency’s head, Dwikorita Karnawati. There is no doubt that flooding will become more frequent and more severe in the coming years.
It was yet another disaster in a terrible year for the Asia-Pacific region. Australia was ravaged by monster wildfires that wiped out unprecedented amounts of forest, farmland and housing. India suffered record-breaking summer heat, with temperatures reaching close to 50C, as experts from the Massachusetts Institute of Technology warned that parts of the country were becoming “too hot to be inhabitable”. When the heat finally broke, Delhi and other parts of the country were blanketed in smog so toxic it was like being in a “gas chamber”, in the words of the city’s chief minister.
This year hasn’t been any better, thanks to the Covid-19 coronavirus that has ravaged the city of Wuhan and spread to every continent except Antarctica. The future looks difficult indeed, but most places in Asia aren’t doing much to prepare for whatever calamity happens next.
“I think only those major cities in Asian developed countries have done some preparations,” says Ren Chao, an associate professor at the University of Hong Kong who studies sustainable urban design. “The rest, especially those in less-developed countries under fast urbanisation, may not put such things on their city development and management agenda.” Ren is echoed by researchers from SEI Asia, an environmental think tank, who wrote last year that Asian cities are “mired in policy inertia when it comes to climate action”.
But there is plenty that can be done. “Architecture is not just the result of response to climate, yet in places where the climate is severe, this is an important role that must be acknowledged,” says Australian architect Carol Marra, who has studied climate-resilient architecture in Asia.
Here’s what’s happening—and could happen—around the region to get Asia ready for an unpredictable and increasingly hostile future.
Learning to Live With Water
In April 2019, the Indonesian government came up with a response to Jakarta’s chronic flood problem: it decided to build an entirely new capital city on the island of Borneo. It also committed US$40 billion to bail out the 30 million people living in the greater Jakarta area from rising sea levels and increasingly severe floods.
How exactly that will be done hasn’t yet been revealed. But in Bangkok, another city prone to flooding, architects have devised ways to mitigate the impact of too much water. When the architects at Landprocess won a bid to design a new park on the campus of Chulalongkorn University, key to their plan was a vast underground container that would siphon off water during the rainy season, saving it for use in the dry season, when Bangkok goes days without precipitation.
“When I was young, I liked floods,” Landprocess founder Kotchakorn Voraakhom told The Guardian after the park opened. “I pushed my little boat out and the road became a canal.” That changed after devastating floods kept large parts of the city under water for months in 2011. “After [that], everyone was like, ‘Oh. What used to be childhood fun has become a disaster,’” said Voraakhom. “And it’s getting worse.”
Landprocess is laying the groundwork for a similar park elsewhere in Bangkok. But what is really needed is a comprehensive plan for civic investment in flood prevention. In Shanghai, the local government has already built 520 kilometres of seawalls to protect itself from rising waters, including a system of mechanical gates similar to those used to keep the low-lying Dutch city of Rotterdam from being submerged.
Tokyo has what many consider to be the world’s best drainage system. Its crown jewel was put in place in 2006 when the Metropolitan Area Outer Underground Discharge Channel opened. It includes 6.3 kilometres of tunnels leading to vast chambers—dubbed by the media as “floodwater cathedrals”—that retain water before it is discharged into the fast-moving Edo River at a rate of 200 tons of water per second.
Hong Kong has also spent decades investing in a vast drainage network that can cope with the intense rainfall caused by tropical depressions. It works hand in hand with an extensive system of slope maintenance. When Hong Kong’s population exploded and urban settlement began crawling up mountainsides in the decades after the Second World War, heavy rains often caused landslides that wiped out entire villages and even concrete tower blocks, as was the case in the Po Shan Road landslide of 1972. That led to a system of monitoring slopes and reinforcing them with concrete and other materials when needed. Today, landslides are relatively rare, even as typhoons grow stronger and more frequent.
But both Tokyo and Hong Kong were responding to conditions as they existed in the past. The future promises to bring even more challenges. That’s where the concept of “sponge cities” comes in. Pioneered by the Indian city of Hyderabad, it promotes the idea that water management needs to be a pillar of urban development. In 2015, China’s central government gave the concept legal weight, ordering cities to be able to absorb and reuse 70 per cent of rainwater.
In the planned new town of Nanhui on the eastern outskirts of Shanghai, being a sponge city means creating wetlands that can naturally manage water, putting green roofs atop buildings and building permeable pavements that can soak up moisture. Similar measures can be found around Asia, including in Singapore, where concrete drainage channels are being naturalised with rocks, soil and marshland.
Beating the Heat
If flooding is becoming more and more of a problem around the world, there’s one major culprit: soaring temperatures. The world is warming at an unprecedented rate, leading to global ice melt and rising sea levels. Another consequence: heat waves that are hotter, longer and deadlier than ever before.
In Hong Kong, Ren Chao was part of the team behind the Urban Climate Map, which tracked temperatures across the city. The study revealed that urban development has created a series of microclimates, with some areas far hotter than others, thanks to high-rises that block the wind and concrete that radiates heat at night. Since the map project was finished in 2012, Ren has been evaluating the impact of this temperature variation.
“We mapped out the spatial distribution of hot nights and hot days in Hong Kong and also conducted heat-related mortality and morbidity research,” says Ren. “We found that our citizens’ health condition has been and will be affected continuously by hot nights, given our dense and compact urban setting and emerging changing climate. This is a new and interesting result, which is different from UK or US studies. I believe most Asian high-density cities may have similar issues. It means we have to design our city properly and carefully control urban density.”
Green space is important, since vegetation helps mitigate the effects of buildings and paved surfaces that store up and release heat. So is ventilation. Last year, Ren and other researchers helped the Hong Kong Green Building Council develop a guidebook on climate-sensitive design. She has also been working with China’s Ministry of Natural Resources to develop new guidelines for urban development that aim to create cooler cities.
It may also be useful to look to the past. Before they became densely packed agglomerations of concrete boxes, Asian cities were far more adept at keeping cool without needing environmentally destructive air conditioning. Carol Marra has studied what she calls “architecture of resilience”, which developed through many generations in response to local environmental conditions.
There are many examples. In China and areas where Chinese people settled, courtyard houses were the norm, not only because they accommodated large, multigenerational households, but because their blend of indoor and outdoor spaces was inherently flexible. “The size, shape, height and detail of the courtyard vary according to location and prevailing climate,” says Marra. In the sweltering heat of Southeast Asia, timber stilt houses were the norm. They avoided floods by being raised off the ground, and their elevated position and high ceilings ensured a constant cooling breeze.
The trick is to learn from the past without necessarily recreating it. “It is not necessary to copy the form or materials of these buildings, but rather to relearn the principles behind the design which accommodate climate,” says Marra. “It then becomes possible to adapt these principles to new building forms, larger buildings or whole neighbourhoods.”
Marra’s own work, in collaboration with partner Ken Yeh, has adapted these lessons to contemporary needs. The Stiletto House in Malaysia marries the form of a traditional Malay house with contemporary technology to create a living space that is cool without air conditioning, and that captures and reuses rainwater. “[It] produces almost three times more energy than it uses and sells the excess back to the grid,” says Marra. In Sydney, Courtyard House #65 makes use of a moveable roof to optimise natural ventilation and light.
Designing Healthy Cities
Fresh air and light are crucial to preventing disease, which thrives in overcrowded urban environments. Sars was spread by faulty plumbing in the densely packed Amoy Gardens housing estate in Hong Kong. More than a century earlier, squalid living conditions in the city’s Tai Ping Shan neighbourhood led to an outbreak of the bubonic plague. In response, that neighbourhood was razed and rebuilt with more spacious streets and the city’s first public park.
It’s hard to say what lasting impact the current Covid-19 coronavirus epidemic will have on cities around Asia. But Ren says urban planning and architecture are key players in the fight to prevent such diseases from running rampant. “When we develop a city, we should consider the basic natural environmental factors such as sun, light and wind,” she says. Good ventilation helps prevent exposure to airborne diseases, something that has long been known.
But viruses are sneaky, and even though improved living conditions have mostly done away with previously tenacious diseases such as tuberculosis, new ones like Covid-19 keep cropping up. “It is definitely not easy to balance the need for high-density living with the risk of such diseases,” says Ren.
Nicholas Ho, managing director of Hong Kong-based HPA, says disease prevention is a concern in many of his projects. “Containment for dirty areas, such as disposal channels, sanitary fitment and sewage, with smart devices, good water traps to prevent re-entry, immunised design and a lot of ventilation” are ways to cope, he says. “We have invested in a company, Negawatt, that pioneered an immunised building design approach for monitoring and response. The founder helped discover and resolve the spread of Sars back in 2003.”
As cities deal with the havoc wreaked by climate change, they’ll be doing so with a population that is older than ever before. Asia’s richest countries are also ageing fastest, with Japan leading the way: the country’s Ministry of Health, Labour and Welfare estimates that 40 per cent of the population will be over the age of 65 in 2040. China won’t fare much better, with 35 per cent of its population over 65 by then.
Ho says responding to an ageing population is a thread that runs through many of his projects. “Universal barrier-free access is the basis for inclusive design, as we want people of all ages to be able to roam freely, safely and securely within the same premises which they call home,” he says. “Inclusive community also includes flexible spaces that can transform for different uses with a strong focus on medical and emergency accessibility and support.”
In Singapore, the Home Farm concept goes a step further by creating a high-density retirement community infused with productive agricultural spaces. “There’s no hinterland in Singapore. [The Home Farm] can produce food while also at the same time creating a nice environment for the people who live there,” says Wai Wing-yun, part of the team at Spark Architects that developed the concept.
The vision generated considerable buzz when it was unveiled in 2014, and since then, Wai says, Spark has been approached by developers and government agencies looking to incorporate some aspects of the concept into their projects. It would not only provide a quality life to the elderly, but would provide a low-energy, sustainable food source for them, too.
It’s a reminder that all of these issues are interconnected. The future will be complicated, but there’s no reason to face it unprepared.
Want to see more from Tatler Hong Kong? You can now download and read our full April issue for free. Simply click here and use the code THKApril2020 to redeem your free issue.
Please note, the free download is available from 6 April, 2020 and is valid until 30 April, 2020.