Advocates of City living and cities like Shanghai (population 24 million) point to economies of scale that result from growth. According to Geoffrey West, in his book Scale (2017), there is economy of scale in infrastructure provision in all cities, with an exponent of about 0.85, so that fewer roads and electrical cables are needed per capita in the bigger city. Thus doubling of city size increases per capita infrastructure costs by 2^0.85 = 1.80 or 90%. This is not much of a saving for doubling city size, but comparing a town of 2,000 with a city of 2,000,000 the per capita infrastructure cost would increase by 1000^0.85 = 355 not 1000, or 35.5% which is a significant saving and could explain why it is cheaper to live in cities than towns. Are West’s economies of scale real? His economies may be simply the loss of amenity and transportation in large conurbations compared with country towns.

In the political crime fiction thriller Presumed Dead, the setting exposes the dynamic of city growth: https://wp.me/P1z4yo-n