Every time I hear people agonizing over the possible ill effects of big data, I think of Dhaka, a city that is being choked by traffic. We all know that the solutions to transport management are among the most difficult to implement. We know that, in fact, there are no perfect solutions. Public transport is part of the answer but not all of it. Congestion pricing, by itself, cannot solve problems. The very complexity of the problem requires that we understand the problem and that we actually have the tools to test components of solutions to ensure that they are effective and that they do not cause additional problems. This is where big data comes in.
It might not be as sexy as building schools or curing malaria, but alleviating traffic congestion is one of the defining development challenges of our time. Half the world’s population already lives in cities, and the United Nations estimates that proportion will rise to nearly 70 percent by 2050.
Of the 23 “megacities” identified by the United Nations, only five are in high-income countries, places with the infrastructure (physical, political, economic, you name it) to deal with the increasing queues of cars snarling up the roads. Mexico City adds two cars to its roads for every person it adds to its population. In India, the ratio is three to one.
Dhaka, the world’s densest and fastest-growing city by some measures, and its twentieth-largest by population, is a case study in how this problem got so bad—and why it’s so difficult to solve.