Scalability and path dependency in urban planning

Providing a cogent reminder of the fact that scale matters in things like economics and urban planning just like it does in the natural world, a traffic jam between Jining and Beijing is now entering its 9th straight day of existence. Hat tip on that goes to Tyler Cowen at Marginal Revolution.

I lived in Beijing for the better part of a year after college and the traffic was awful even then. I remember one of the first things I heard about transport in the city was that the percent of urban area devoted to roads (or "road area ratio" in planning parlance) was vastly less than in other comparably-sized cities. Poking around a bit on Google Scholar yields a figure around 12% vs. cities like London being in the range of 35% and American commuter cities being in the range of 45% (Ge and Ping, 2008).

Abstracting a bit more, news like this makes me more sanguine about predictions that India and China are seeking to completely emulate American lifestyles, thereby placing an unbearable load on the Earth's resource base. If very deeply-rooted structural differences make owning personal vehicles this much of a pain this early in a country's development trajectory then I think the long-term prospects have to be fundamentally different. Recall that the Americas (ok, and Australia) were built more or less from scratch over the past two centuries while a lot of new transport and housing technologies were being developed and demographic changes were being realized. Expecting countries with longer histories and different cultural biases to have their pre-existing large cities turn into L.A. just because per capita incomes have gone up seems a bit simplistic.

Though I'm sure traffic in L.A. sometimes seems to last for days on end.

*Image copyright AP.

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