“If the last century was the century of urbanisation, the twenty-first will be the century of cities. It is in the cities that decisive battles for the quality of life will be fought, and their outcomes will have a defining effect on the planet’s environment and on human relations.”

So writes Jaime Lerner, a former governor of southern Brazil’s Paraná state and former mayor of Curitiba, Paraná’s capital, in his forward to the Worldwatch Institute’s just-released annual report, State of the World 2007: Our Urban Future. An internationally recognised architect and urban planner, Lerner knows of what he speaks. During his years in office in rapidly developing Brazil, he implemented numerous social, ecological and urban reforms, including an integrated transportation system in Curitiba that has caught the attention of mayors and urban planners in the Americas, China and elsewhere.

The significance of this new, global urban supremacy -- for both people and planet – is profound, and the statistics are stark: About 35% of the population of Africa and Asia is now urban -- a figure that is expected to stand at 50% by 2030. From 1970 to 2000, just 4% of the $1.5 trillion in development assistance worldwide was for urban aid. And while cities cover a mere 0.4% of the earth’s surface, they generate the bulk of the planet’s carbon emissions.

Sometime in 2008, a threshold will be crossed: the point at which more people – roughly 3.2 billion human beings -- will be living in the world’s urban areas than in its rural ones. Between now and 2030, the population of the earth is projected to grow by 1.1 billion, according to the Worldwatch report. If global development priorities are not reassessed to account for massive urban poverty, well over half of these newcomers may end up living in under-serviced slums: urban settlements in developing countries without such necessities as clean and convenient water and sanitation facilities, health care and durable housing.

“The combined impact of a growing population and an unprecedented wave of migration from the countryside means that over 50 million people – equivalent to the population of France – are now added to the world’s cities and suburbs each year,” says Worldwatch’s president, Christopher Flavin, in his preface to Our Urban Future.

 “More than at any other time in history,” writes Flavin, “the future of humanity, our economy, and the planet that supports us will be determined in the world’s cities.”

As cities become more populated, more and more of the world’s energy-hungry buildings are taking form there. Worldwide, buildings account for more than 40% of total energy use. Much of that energy – particularly in urban areas -- is heavily reliant on fossil fuels, the primary engine of global climate change. And, of course, as China booms economically, the country is increasingly a key factor in the planet’s urban future. Already home to 16 of the world’s most polluted cities, China sees millions of its people move to cities each year.

“In 2005,” the Worldwatch report says, “Shanghai constructed more building space than exists in all the office buildings of New York City. Every month, China adds urban infrastructure equal to that found in Houston, Texas, simply to keep up with the masses of people migrating from rural areas to cities.”

Unlike many people, who fear that an increasingly urbanised future will mean more problems than solutions for the planet, Flavin (like Lerner and others who contributed to the new Worldwatch report) views cities not as “hopeless and apocalyptic places” but as “exciting laboratories of change”. Such optimism, he insists, “is central to the future of cities – and the world itself.”

photo by Java Cafe

Like it or not, the global future will be urban. So, what can be done to improve that future, to fight poverty and environmental injustice in cities? The 250-page report addresses a wide range of practical topics, including urban farming, green transportation, energy efficiency, natural-disaster risks, public health and sanitation, and local economics. While acknowledging that “there is no magic bullet for creating sustainable, equitable and peaceful cities,” Our Urban Future points to five “necessary if not sufficient conditions for such transformations.”

Spelled out by Janice E. Perlman, a consultant on urban poverty and environmental justice issues, and Molly O’Meara Sheehan, State of the World 2007’s project director, they are:

-- Transparent governance. This includes confronting corruption by fostering competition, which in turn would reduce bureaucratic leeway and increase accountability. The report cited La Paz, Bolivia, where bribery in construction permits was reduced by simplifying and advertising the rules, contracting-out the permitting to architects, and reducing the city’s role to oversight carried out by fewer (and better paid) municipal employees.

-- Decent work or a basic income. For the urban poor, jobs – which afford dignity – are a key factor. Job creation, as well as skills-training work in growing market sectors, is needed. So, too, is access to financial tools such as savings and credit, including the many forms of microfinance. Large companies can play an important role, as in Mexico, where the cement company CEMEX developed a scheme by which low-income families can buy materials to build and improve their housing. Local governments can hire the urban poor to help address environmental problems, such as in a Rio de Janeiro community reforestation project to protect the city’s vulnerable shantytowns from flooding. Contracted local workers also have carried out rebuilding after flooding in Dar-es-Salaam, Tanzania, and Kampala, Uganda. “Conditional cash transfer programmes” – by which low-income families receive cash as an incentive for desirable actions, such as sending children to school or having them immunised against contagious diseases – also have a role to play.

-- Innovations in conservation. Cities without full infrastructure, including much of China, can “leapfrog” over outmoded, wasteful systems dating back to the Industrial Revolution and start with twenty-first century technology. The built environment can be revolutionised by taking advantage of high- and low-tech resource-conservation strategies: installing water-conserving toilets, separating drinking and grey-water systems, using passive solar energy or biogas for heating. Some projects in China will use biogas from wastewater for cooking, passive solar energy for heating and cooling and compressed earth for building materials. Indeed, the eastern coastal city of Rizhao, in Shandong province – home to nearly 3 million people – is a model municipality. Local leaders see the city’s enhanced environment – thanks to the wide use of solar power -- as a key to long-term improvements in its social, economic and cultural spheres.

-- Intelligent land use and integrated community development. Old planning tools can be used for progressive change. For example, zoning, building and land-use regulations can be adapted “to foster mixed-use communities, with homes close to workplaces, commerce and recreation”. Development in areas with infrastructure in place can help to limit urban sprawl. Special-interest areas can be set up, protecting environmentally important areas and connecting nature corridors. In Brazil, São Paulo has led the way in creating a more inclusive city. One key step was taxing developers to create a fund for such public-interest investments as public transportation, housing and environmental upgrading. Dakar, Senegal, first tested a “sites and services” approach, by which small plots of land are laid out with connection to basic services and made available -- for small sums or loans -- to new migrants. (Retrofitting a squatter community is far more expensive.)

-- Social cohesion and cultural diversity. Cities can be strengthened by cultural diversity, which makes human economics (like natural ecosystems) more resilient. In urban areas -- torn by violent crime that further isolates the poor -- the sale of guns and drugs needs to be controlled, along with the corruption that allows such activities to continue. Among initiatives considered promising are: community policing in low-income neighbourhoods; arts, culture and sports programmes for at-risk young people, and weapons amnesties.

Perlman, who founded the Mega-Cities Project in 1987 to address issues of urban poverty, notes that poor urban neighbourhoods are afflicted by “the worst of two worlds” -- the environmental health hazards of both underdevelopment and industrialisation. “Yet their residents tread lightly on the planet … The gap between rich and poor in cities from Nairobi to New York means that those with the fewest resources suffer most from pollution generated by the wealthiest.”

Indeed, the report says, “[t]he logical sequence linking global sustainability to urban poverty is synthesised in what have become known as the Perlman Principles.” In short:

-- There can be no global environmental sustainability without urban environmental sustainability.

-- There can be no urban environmental solution without alleviating urban poverty.

-- There can be no solutions to poverty or environmental degradation without building on bottom-up, community-based innovations.

-- There can be no impact at the macro level without sharing what works among local leaders and scaling these programs up into public policy where circumstances permit.

-- There can be no urban transformation without changing the old incentive system, the “rules of the game” and the players at the table.

-- There can be no sustainable city in the twenty-first century without social justice and political participation as well as economic vitality and ecological regeneration.

Approaches that work should be shared globally and, given the magnitude and urgency of the challenges ahead, it is important to start now, the Worldwatch report maintains. “Imagine the ideal, but do what is possible today,” urges Brazil’s Jaime Lerner. Mobility, sustainability and identity need to be addressed, he writes. Transport systems need to be combined and integrated. Urban infrastructure needs to have multiple functions, to be utilised 24 hours a day, for maximum saving and minimal waste. Riverbanks, parks and historic districts need to be nurtured to maintain quality of life and self-esteem for everyone living in an urban environment.

 “A city is a collective dream,” Lerner asserts. “To build this dream is vital. … Cities are the refuge of solidarity. They can be the safeguards of the inhumane consequences of the globalisation process. They can defend us from extraterritoriality and the lack of identity.

“On the other hand, the fiercest wars are happening in cities, in their marginalised peripheries, in the clash between wealthy enclaves and deprived ghettoes. The heaviest environmental burdens are being generated there, too, due to our lack of empathy for present and future generations.

“And this is exactly why it is in our cities that we can make the most progress toward a more peaceful and balanced planet, so we can look at an urban world with optimism instead of fear.”

Maryann Bird is a London-based freelance journalist with a special interest in environmental and human-rights issues. A writer and editor, she was previously a staff member at Time magazine (Europe), The Independent, the International Herald Tribune and The New York Times.