© Courtesy of Eriksson Architects LTD.

Are made-from-scratch metropolises the answer to Asia's urban overpopulation?

Two years ago, 35 miles southwest of Seoul, developer Stan Gale cut the ribbon on the world's newest city-a man-made isthmus in the Yellow Sea named Songdo International Business District. In 2001, the chairman of New York-based Gale International had pledged to borrow $35 billion to build a city the size of downtown Boston, modeled on Paris, Venice and Manhattan, complete with a hundred-acre "Central Park." Songdo won't be finished until at least 2016, but Gale isn't waiting around. These days, he's pitching China's mayors on his city-in-a-box-a kit to build their own smart, green city of the future in as little as three years.

Is it even possible to build a city from scratch, at least one we would want to live in? This may be the defining challenge of our era. The earth's urban population will nearly double by 2050, requiring the construction of hundreds of new cities. China is already building the equivalent of a Rome every few weeks to absorb the 400 million migrants streaming in from the countryside. The question facing us as an urban species isn't whether to build cities tabula rasa, but how. And nowhere is this dilemma more pressing than in Asia.

The archetypal Asian city isn't Art Deco Shanghai or postwar Tokyo, but the "overnight city" of Shenzhen, which was just a fishing village when it was tapped to be China's capitalist enclave more than 30 years ago. Today, it's a sprawling metropolis of nearly 14 million, with clusters of skyscrapers sprouting from an impenetrable canopy of factories and elevated highways. Unplanned and uncontrollable, Shenzhen and its neighboring cities represent 20th-century urbanism at its worst-ugly, inequitable and unsustainable. Surely we can do better in the 21st?

Plans for utopian cities date back to the Renaissance, although a modern example is Brasília, the Oscar Niemeyer-designed, made-to-order capital built over 41 frenzied months in the 1950s. Following Brazil's lead, Malaysia started construction on its own new administrative center in the mid-'90s. Rubber and palm-oil plantations were chopped down to make room for the domes and spires of Putrajaya and its sister city, Cyberjaya, which are linked to Kuala Lumpur, 15 miles to the north, via a fiber-optic "multimedia super corridor."

Cyberjaya, which was supposed to be Southeast Asia's answer to Silicon Valley, never attracted the country's entrepreneurs. And Putrajaya ended up being a quiet, manicured campus for technocrats. Korea's Sejong, a "multifunctional administrative city" a two-hour drive south of Seoul, will likely face the same fate when the first residential zone is completed in December. Originally envisioned as the new capital, it is now slated to become the home of certain government ministries. (Last year a power struggle over Sejong's fate threatened to split the ruling Grand National Party in two, and critics doubt that many officials will actually move there from Seoul.)

More than politics, sustainability is the driving force behind these instant cities. The half of humanity that now lives in urban areas is responsible for 75 percent of all energy consumption, so building cleaner cities is key to combating climate change. This goes double for China, the world's biggest polluter. What's missing is a prototype for the cities environmentalists have in mind. Lying west of Beijing-the home of weeklong traffic jams-Mentougou Eco Valley aims to be the first.

Designed by Helsinki's Eriksson Architects and scheduled for completion around 2016, Mentougou will have floating geodesic domes and solar panels dotting the hillsides, hiding the scars of former strip mines. Nestled in the valley will be nine research institutes, each devoted to an aspect of the city's sustainability, whether water treatment, traffic or energy. Mentougou's 20,000 residents will double as the subjects in a larger experiment. "The idea was to develop the perfect ecological city," says Eriksson founder Patrick Eriksson, but the developers will settle for cutting carbon emissions to below a third of the average.

On the far side of Beijing, the historic city of Langfang, whose population is near 800,000, has hired the architects of international firm HOK and San Francisco's CW Group to retrofit it using a technique known as biomimicry. Langfang Eco-Smart City will mimic the forests that once stood on the spot using treelined walkways and "blueway" canals to circulate and conserve water as the tree roots and wetlands once did. A network of streetcars will connect to the city's dominant feature: a station on the new Beijing-Shanghai high-speed rail line.

China's biggest-ticket green city lies farther east, on the outskirts of Tianjin, Beijing's gritty answer to Newark, New Jersey or Long Beach, California. As its tongue-twisting name implies, Sino-Singapore Tianjin Eco-City is a joint venture between two nations-an audacious effort to build the clean-tech industry's Silicon Valley, once again using an entire city as a laboratory. Slated to be larger than New Orleans, Eco-City will replace a brackish wasteland with a "Lifescape" and "Urbanscape" of terraced hills and high-rises, all comprised of swooping arabesques.

The goal with both Eco-City and its nascent cousin, Sino-Singapore Guangzhou Knowledge City, the planned home of 500,000 due to open in southern China in 2014, is to write an instruction manual for green cities that any bureaucrat can follow. In Knowledge City's case, this translates into an obsession with a city's "software"-not the digital code humming beneath its screens, but the policies, practices, ways and means of building and managing one.

The most ambitious instant city of all remains Songdo. Originally commissioned by the Korean government to lure multinationals from Singapore and Hong Kong, Songdo is less a Korean city than a Western one floating just offshore from Seoul. Eschewing the sci-fi trappings of Tianjin or Mentougou, Songdo's architects at the international firm Kohn Pedersen Fox Associates chose to use the signatures of beloved cities-Savannah's gardens, Venice's canals-as building blocks. (The golf course is courtesy of Jack Nicklaus.) This model has proved wildly popular with middle- and upper-middle-class Koreans, who bought the first 1,600 apartments in a weekend scramble in May 2005. More than half of Songdo's 65,000 envisioned residents already live there; the rest are expected to move in by 2016.

Songdo, too, is touted as being one of the world's greenest, most energy-efficient cities. Buildings will boast solar panels and sod on their roofs, and 75 percent of all water and waste will be recycled. Most of the city will be wired with digital synapses-from the trunk lines running beneath the streets to the filaments branching through the walls and fixtures. To what end? Stan Gale and his partners at Cisco Systems aren't sure, but imagine if a city operated like an iPhone-and they could sell apps for everyday life.

Whether out of greed, desire for prestige or sheer necessity, instant-city builders of all stripes seem to believe new cities should conform to Moore's law: faster, better, cheaper. Just as this mentality produced the high-speed rail crash that has shaken China's faith in progress to its core, it has also produced a municipal debt bubble running into the trillions of dollars. Will the effort to build the perfect city produce the perfect economic storm instead? Even Songdo, which is widely perceived as the most successful example, has struggled under the weight of its financial burdens. "The third owner typically makes the profit on these projects," says Gale. "I'm trying to buck that trend."

Whether any of these cities will be as smart or as green as they promise remains to be seen, but their creators are convinced that the world needs a better model than the urban free-for-all of Shenzhen. "Less land, less energy, more recycling and more reuse," says Ko Kheng Hwa, CEO of Singbridge, the Singaporean developer of Guangzhou Knowledge City. Building an instant city may be problematic, but it's far better than the alternative.

Mentougou Eco Valley, China: Twenty-five miles west of Beijing, Mentougou Eco Valley will have nine environmental research institutes when completed in 2016. The water facility was designed to look like droplets and will study pollution levels and the river's ecosystem.

Sejong, South Korea: Originally planned as Korea's new capital city, Sejong will be the new home of 36 government agencies, including the Ministries of Environment, Strategy and Finance, and Employment and Labor, by 2014. Set to open in 2013, the new National Library will eventually hold six million volumes.

Songdo, South Korea: Across a sweeping seven-mile bridge from Seoul's Incheon International Airport, Songdo alreadyhas around 35,000 residents in advance of its 2016 completion date. When finished next year, the 68-story Northeast Asia Tower, at one end of the city's Central Park, will be Korea's tallest building.

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