In announcing plans for Shanghai, China also defined “big city disease”:

China’s financial hub of Shanghai will limit its population to 25 million people by 2035 as part of a quest to manage “big city disease”, the cabinet has said…

State media has defined “big city disease” as arising when a megacity becomes plagued with environmental pollution, traffic congestion and a shortage of public services, including education and medical care.

Many of China’s biggest cities also face surging house prices, stirring fears of a property bubble.

This leads to two thoughts:

1. If China, a country devoted to urbanization, thinks this is the population limit for big cities, does this mean other industrialized countries will follow suit?
2. It would be interesting to hear urban experts weigh on regarding how big they think major cities can get. Twenty-five million people is quite a few but can some of the issues Chinese officials raise be ameliorated by good planning or technological advances?

Perhaps one of the key features of major global cities of the future will be a limited population size in order to have a certain quality of life. In contrast, major cities that are not as important may grow to unheard of sizes with all sorts of symptoms of “big city disease.”