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How to manage urban expansion in mega-metropolitan areas?

Philip E. Karp's picture

As the world becomes increasingly urbanized, the number of megacities is growing rapidly.

Today there are 37 cities worldwide with populations of greater than 10 million, and 84 with populations greater than five million. More than three quarters of these cities are in developing countries. Together with their surrounding metropolitan areas, these cities produce a sizable portion of the world’s wealth and attract a large share of global talent.

These megacities face a series of common challenges associated with managing urban expansion, density, and livability—in a manner that takes advantage of the benefits of productive agglomerations, while mitigating the disadvantages of such high degrees of congestion and urban density.

Moreover, like other metropolitan areas, megacities face challenges of effectively coordinated planning, infrastructure development, and service delivery across multiple jurisdictions. Indeed, the New Urban Agenda issued at the Habitat III conference in 2016 identified metropolitan planning and management as one of the most critical needs to ensure sustainable urbanization.

Transforming Karachi, Pakistan into a livable and competitive megacity

Jon Kher Kaw's picture
It will take Karachi as much as $10 billion of capital investment over the next decade to close the infrastructure gaps in the city.
On the ground, it is not too difficult to see why this is so. More than 40% of residents rely on public transport, but with 45 residents competing for one bus seat, travel within the city is difficult. Water supply is highly irregular, and rationing is widespread. The availability of water ranges from four hours per day to two hours every other day. Many households rely on private vendors who sell water from tankers at high prices. The sewage network has not been well maintained since the 1960s, and all three existing treatment plants are dysfunctional. Industrial waste, which contains hazardous materials and heavy oils, is dumped directly into the sea untreated. Of the 12,000 tons of municipal solid waste generated each day, 60% never reaches a dumpsite; 80% of medical waste is not disposed of properly.
Garbage accumulated on a road median in Karachi. Photo: Annie Bidgood / World Bank