How green architecture is transforming our polluted metropolises into eco-friendly urban jungles.

Modern cities can be depressingly barren places. We’ve come to see the city in opposition to the countryside. The former is all about commerce and concrete, the latter a bucolic idyll. But this stark division between the urban and the rural is a relatively recent concept. In the past, cities tended to hug nature far more closely.

The Hanging Gardens Of Babylon remain such an enduring image because there’s something incredibly seductive about the idea of making the city bloom. Although they were probably mythical in their scale, there’s plenty of archaeological evidence across the ancient world, from Assyria to Rome to Tenochtitlan, of complex urban irrigation and cultivation.

It’s clear. People like plants, but for much of the 19th and 20th centuries, they were not essential parts of our urban environs. The cold rationality of the Industrial Revolution privileged geometric avenues and churning mills, and left little space for an organic riot of blooms and boughs, save for in constrained municipal parks. Today, this is changing, and green architecture projects have been popping up like mushrooms everywhere from Singapore to Seattle. Instead of declaring a rollback on urbanisation, these projects use cutting-edge technology and innovative design to turn the urban jungle into something approaching an actual jungle.

One of the main impetuses behind the rise of these urban Edens is that pollution levels have reached crisis point. According to the World Health Organization, 92 per cent of the world’s population now live in places where pollution exceeds acceptable levels, and air pollution now represents the fourth greatest threat to human life (after blood pressure, diet and smoking). Chronic pollution is often painted as a problem faced in the sprawling metropolises of east Asia and South America, but many European and North American capitals are just as toxic. London smashed its annual pollution limit in the first five days of 2017 and Paris has resorted to number plate lotteries to curb car use during periods of peak pollution.

“Cities are our greatest invention because they are places where we learn to live with others who aren’t like us,” says Mr Dan Hill, associate director at design, architecture and engineering consultancy Arup. “However, the selfish, individualist politics we see around us today are the exact opposite of what makes a city great. The city is intrinsically about shared resources, shared spaces, shared ideals and dreams.” Compare this utopian vision with how most cities are run today, as competing public- and private-interest groups that often have no coherent vision. We have reached an impasse where livability and wellbeing come second to cold, hard cash.

“Cities have become machines that are killing us, and that’s just weird,” says Mr Daan Roosegaarde, the Dutch designer who creates ambitious projects that harvest smog from the air and light pathways with natural bioluminescence. “East Asia is taking a leap and the lead, and that’s not because they’re hippies. It’s because they realise that this is the only way to be future-proof. It’s not just about being responsible. It’s about being strategic.”

Perhaps the most ambitious example of this green architecture trend is Mr Stefano Boeri’s Liuzhou Forest City, which is now under construction in southern China and scheduled for completion in 2020. This colossal complex will house 30,000 people, but also more than one million plants and 40,000 trees, meaning it will absorb almost 10,000 tonnes of carbon dioxide per year and churn out 900 tonnes of oxygen. Commissioned by the Chinese municipal government, Liuzhou Forest City has echoes across east Asia, often undertaken by private companies. Singapore’s Parkroyal On Pickering combines office and hotel space in a vast 15,000sq m tiered garden. This latter-day Babylon is designed to be as self-sustaining as possible, with a complex irrigation system that captures rainwater and distributes it throughout the terraces, with infinity pools to gather and store it. Singapore has also made its name as a green architecture centre with developments such as the Editt Ecological Tower and Gardens By The Bay.

This isn’t to say that green developments are absent from Western cities, and fans of Mr Boeri will know that the man has form in this area. His Bosco Verticale in Milan is a forested skyscraper that has managed to pack almost 800 trees and 16,000 plants into a single high-rise development, claiming to offer the equivalent of 20,000sq m of undergrowth. American architect Mr Daniel Libeskind has just got the green light for his ambitious Occitanie Tower in Toulouse, promising a twisting edifice of glass and greenery that will echo the meanderings of the nearby Canal Du Midi. Private corporations are also catching on to the fact that access to nature boosts worker wellbeing (by about 47 per cent, according to recent research from the University of Exeter). The new Google campus in London, designed by Mr Thomas Heatherwick and Denmark’s BIG architects, will have a huge park, running track and swimming pool on the roof, and has just been approved, four years after the original AHMM design was reportedly scrapped for being “too boring”. Going one step further, Amazon’s new NBBJ-designed headquarters in Seattle will be set in three 35m-tall biodomes that will contain a plethora of tropical plant life, bringing a new layer of meaning to “Amazonian”.

The general problem is that many of these eye-catching developments, wherever they are in the world, feel more like tourist attractions than genuine future models for urban architecture. “There are some fantastic projects out there, but we have to ask ourselves if they are purely decorative or truly reforming,” says Mr Roosegaarde. “It’s not enough to copy and paste from nature. We need to copy-morph and add more of a technological lens to tackle the issue on multiple levels.” Humans have introduced new pressures on the global ecosystem, so we need to come up with new solutions, too. Planting some trees on the roof may not be enough.

Our barrier to creating truly green cities is no longer technological or financial. It’s about creating consensus about a future we have to invest in. We need to move away from seeing urban ecology as a bit of social responsibility that we should invest in to offset bad behaviour elsewhere. Green design needs to be embraced as a positive and, most importantly, commercially viable future for living in high-density spaces. And the good news is we can all play a part here. It can’t just fall on the shoulders of urban planners, architects and politicians. It is also the responsibility of the public. We can make our voices heard through campaigns and purchasing power, and demand that green developments become the norm, not the novelty.