x Abu Dhabi, UAEWednesday 24 January 2018

City limits

Books With over half the world living in urban areas - and more people joining them every day - our lives are increasingly determined by how well those areas are organised.

With over half the world living in urban areas - and more people joining them every day - our lives are increasingly determined by how well those areas are organised. Bradford Plumer considers a new survey of recent successes and failure. Welcome to the Urban Revolution: How Cities Are Changing the World Jeb Brugmann Bloomsbury Dh110 At some point in 2007, the planet hit a major milestone. For the first time in human history, more people were living in urban areas than in the rural countryside. We'll never know who, exactly, tipped the scales once and for all. Was it an Indian farm labourer, riding a bus into Madras to seek out work at a brickyard? Was it a young Kenyan teenager, leaving his parents for the sweltering slums of Nairobi, hoping to earn enough money to send back home?

The details hardly matter. What matters is that similar stories are repeating all over the world at a frenetic pace. By 2030, according to UN projections, some five billion people will live in urban areas, up from three billion today. Asia and Africa will see their urban populations double in the next 25 years. (Most of the growth will occur not in behemoth cities like Mumbai or Lagos, but in midsized cities like Peshawar or Wuhan.) True, Europe went through just such a shift during and after the Industrial Revolution, but that took place over a much longer timescale, and the tens of millions of emigrants who were departing for North America helped ease the strain on European cities -such exoduses are much less likely in an age of border restrictions. Really, no previous urban migration even begins to compare in size and scale with what's happening today.

What will this great rush to cities portend? Probably a mix of good and ill. True, urban poverty will skyrocket: by 2025, two billion people will have crowded into urban slums around the world, huddled in tents amid overflowing pit latrines, or in tiny metal shacks on craggy hillsides. But even slum-dwellers often have more chances to move up in the world than rural subsistence farmers. Yes, crime and violence could explode, but so will educational opportunities, especially for women. It's also tricky to predict how mass urbanisation will affect global politics. Historically, cities have served as focal points for pro-democracy movements like Poland's Solidarity, which gelled together in the buzz of urban life, where totalitarian leaders couldn't regulate the millions of informal interactions and private chats that take place on a daily basis. Likewise, in modern-day China, most of the protests and riots have come about not via the internet - which Beijing has rather deftly constrained - but in cities like Shenzen and Changchun, where workers have erupted during local disputes over urban management.

How this urban future unfolds will depend, to a large extent, on how well cities are actually planned and governed. That's the question at the heart of Jeb Brugmann's new book, Welcome to the Urban Revolution. It's not hard, Brugmann points out, to see why literally all the world is flocking to cities. Economies of scale, density, proximity, ease of association - these traits all make urban economies incredibly vibrant and attractive. Ideally, cities should want to maintain those advantages as they grow.

But over and over again, local planners fail to grasp just what it is that makes cities work so well. Just look at California's Silicon Valley, once viewed as the ultimate tribute to the benefits of urban agglomeration. During the 1980s and 1990s, Silicon Valley thrived due to the more than 140 software, electronics and biotech companies that clustered in Stanford Research Park - itself a top research centre linked to a world-class university. Yet in recent years the Santa Clara Valley has become bogged in a gnarl of sprawl and far-flung suburban developments, leading to rising housing costs, congestion and geographical segregation that threaten to undermine the very efficiencies that put Silicon Valley on the map. "The genius of the region's early urbanism," Brugmann observes, "was poorly understood."

In developing countries, the stakes are even higher. Brugmann takes his readers on a long tour of Dharavi, a slum neighbourhood in south-central Mumbai, home to as many as one million people packed some 300,000 people per square kilometre (25 times more dense than London). What looks at first like a Hobbesian nightmare of squalor and trash actually has its own compelling urban logic, Brugmann explains. The neighbourhood's tight density, cheap land and low transportation costs have conspired to create a robust urban ecosystem, filled with shops, manufacturers and trading outposts that offer genuine opportunities for incoming migrants to improve their lives. The city is hardly idyllic, what with the crush of people, the lack of sanitation, the stench of industry. But Brugmann argues that a recent plan to tear down the slums and rebuild the area into a high-rise residential district runs the risk of disrupting the thousands of subtle, delicate economic relationships that have allowed Dharavi to thrive.

The larger theme of this book, very much reminiscent of Jane Jacobs's influential treatise, The Life and Death of Great American Cities, is that urban planning needs to build slowly and carefully atop what already exists in a city, to heed the organic "citysystems" that are pulsing just below the surface. As an example of what not to do, Brugmann cites the Malaysian city of Putrajaya, which was renovated from top to bottom during the 1990s by ambitious master planners who ended up creating a sterile downtown district - with shiny malls and barracks-like residential areas - that now performs below its economic potential and offers few paths upwards for incoming migrants.

On the brighter side of the spectrum are success stories like Curitiba in Brazil, a city fawned over by New Urbanists and environmentalists, not least because 45 per cent of its passenger trips are taken on public transit, while the city itself is filled with parks, affordable housing and heavily trafficked public squares. Brugmann persuasively argues that Curitiba's success came about because longtime mayor Jamie Lerner and his associates had a coherent vision for urban development that built off existing traditions - Curitiba's vaunted bus system, for instance, was stitched together, slowly and methodically, from hundreds of pre-existing private lines. Heavy public participation was crucial to the city's modernisation plans, as was a stable government. And, as a result of wise planning, the fast-growing Curitiba is better situated to handle the coming avalanche of migrants than bigger neighbours like Brasília or São Paulo.

Brugmann's book has relatively few concrete pieces of advice for urban planners, apart from urging developing countries not to resist the influx of poor migrants from rural areas. (On this, he's quite right; it's shocking to watch governments around the world try to reverse the flow of urbanisation by evicting new migrants or denying them services. In Nairobi, 60 per cent of the population still lives in "informal settlements" that are entirely ignored by city officials.) Indeed, Brugmann's point is that there isn't a clear blueprint for building a city. Every urban region has its own specific culture and traditions, and planners need to heed that. So, rather than a bullet-pointed list of "dos and don'ts", the book tries to identify cities that have successfully realised ambitious social and ecological goals, as well as looking at those cities that have struggled.

Unfortunately, this sort of analysis often comes across as vague, as Brugmann doesn't always offer clear metrics for distinguishing well-planned cities from poorly planned ones. He shows, for example, that downtown Toronto has fallen prey to incoherent (and often conflicting) visions of what the city should look like - as a result, much of the metropolitan area's recent growth has scattered into suburbs and exurbs. Vancouver, by contrast, is deemed a success story, partly because its residential areas are more compact and a greater share of its population uses public transit. Certainly, this is an important aspect of urban policy - proper planning can make an enormous difference on sprawl, and hence a city's gasoline use and carbon emissions. But insofar as Brugmann is concerned with more than just sprawl, as his book seems to be, he never quite identifies what, precisely, makes certain cities such success stories. Is it affordable housing? Good schools? Clean water? Low crime? There seems to be an I-know-it-when-I-see-it quality to many of his judgments.

That aside, Welcome to the Urban Revolution is a consistently insightful look at what makes cities tick - with all sorts of examples of how that gearwork has altered the course of history. On one page, we learn that urbanisation has changed the very nature of romantic relationships, as people in rural areas tend to marry along ethnic lines, while city-dwellers with more options seek out partners of similar education levels. In another chapter, Brugmann shows how the 1979 Islamic revolution in Iran was, in part, triggered by land reforms that created a critical mass of dispossessed urban migrants. (Alas, Brugmann occasionally steps too far in his eagerness to show "how cities are changing the world". His suggestion that Malaysia's urban structure accounts for the country's exposure to the 1997 Asian financial crisis is awfully strained.)

As a final point, however, it's worth wondering whether there are limits to the new urbanism envisioned in this book. Can better planning really alleviate all of the potential problems that the great urban migration will bring? Consider, for instance, Gaborone, Botswana - a city showcased in the UN's State of World Population 2007 report. Gaborone's growth has been mind-boggling: Back in the 1970s, the city was home to just 17,000 people; today it has 186,000 inhabitants, and it will swell to 500,000 by 2020. On the bright side, Gaborone is evolving from a dusty outpost to a financial and industrial hub, with glass-and-steel buildings now dotting the skyline. But the torrid growth has also led to out-of-control sprawl, a worsening Aids epidemic, soaring unemployment, and a proliferation of overcrowded slums.

Those problems can't all be chalked up to a failure of planning. Gaborone, after all, ranks as one of the least corrupt cities in Africa, and has taken thoughtful steps to plan for new expansions, such as renting out fully serviced plots of land to migrants, and cracking down on speculators. But while that has helped low- and middle-income families make the transition to urban life, the very poor continue to stream into makeshift slums that lack clean water or sanitation. Gaborone has adjusted better than a city like Karachi, where slum-dwellers are at the mercy of local political machines, which extract exorbitant rents through threats of eviction. But it's a reminder that the furious pace of urbanisation can overwhelm even the most carefully managed cities. So, in addition, it may be necessary to take a closer look at policies that can help slow the tide, such as more aid for family-planning groups. And it's worth reassessing global trends that have quickened the pace of urbanisation - for instance, the liberalisation of agricultural markets.

To be sure, Brugmann is well aware that the best-laid plans of even the most careful municipal planners can go awry. In one fascinating aside, he notes that Japan's Kanagawa prefecture, which includes Yokohama and Kawasaki, launched an ambitious, multimillion-dollar attempt during the 1990s to green the cities and curb energy use. The plan showed early promise, but it ended up being totally undermined by Japan's corrupt construction industry, which, fuelled by bribes and kickbacks to elected officials, has raced furiously to build unneeded roads, ports and airports that have swamped eco-minded development efforts. Even so, Brugmann's concluding chapter seems quite optimistic that most of the world's cities can develop the "robust, nuanced urbanism" at work in places like Curitiba. It's a hopeful vision. But is it actually justified? That's less clear. As the great global urban migration of the next two decades unfolds, we're bound to find out.

Bradford Plumer is an editor at The New Republic.