As early as the 16th century, the queen of England tried to establish an urban growth boundary around London, which was ultimately unsuccessful in containing the metropolis. In the 19th century, planners in New York City realized they needed to do just the opposite -- and established the grid we know today that stretched far north of the earliest settlement of Manhattan.
The burgeoning cities of the 21st century, primarily in the developing word, must plan for an even greater urban expansion, as visiting fellow Shlomo “Solly” Angel explained at the standing-room only launch event for his book Planet of Cities earlier this month at the World Urban Forum VI in Naples, Italy. Already more than half the world's population lives in cities, and the urban population in the developing world is expected to increase from 2 billion to 4 billion in the coming decades. "We're not making adequate preparations, and we have very little time," Angel said. Avoiding rampant informal settlement with decent, affordable housing for vast numbers of rural migrants is only possible if serviced urban land is in ample supply, he said.
Angel, who also made the case for advanced planning not only for infrastructure but open space as part of an opening dialogue, was part of a Lincoln Institute delegation that included president Gregory K. Ingram, speaking on Habitat for Humanity's Global Housing Policy Indicators project; Martim O. Smolka, leading a training session on slum prevention and improvements; and Armando Carbonell on planning for impacts of climate change, from sea level rise to landslides.
In that roundtable, Jim Kostaras from the Institute for International Urban Development examined water supply depletion from shrinking glacial ice in El Alto, Bolivia, where rural migrants fleeing drought and volatile weather are settling at the urban periphery and digging pirate wells. Kostaras proposed blending land use and hydrological planning to help head off water shortages, contamination, and price spikes.
The five-day summit, called The Urban Future, addressed the staggering challenges of managing growth in global cities, from transportation to housing to basic services such as clean water and sanitation. The next World Urban Forum will be in Medellin in 2014.