At the Atlantic Cities blog, Anthony Flint makes the case that the rapidly growing cities of the developing world can learn a great deal by studying the 19th century plan for Manhattan’s grid. At the time, planners:
were truly making big plans – laying out a grid north from Lower Manhattan and Greenwich Village to 155th Street…The planners had to make a bunch of calculations: the length of the east-west blocks, the length of the north-south blocks, the major avenues, the question of whether to put in radiating streets similar to Washington, D.C., the location and size of squares and parks (the decision to set aside the big intervention of Central Park came later in the century). The city builders were essentially laying out infrastructure and creating a real estate market – a bit of a gift, really, to those lucky enough to buy parcels and take it from there. They even had to confront informal settlement: there were shantytowns of Irish and Italian immigrants all over, at places like 105th Street and 5th Avenue.
Though the prospect of a fully and densely urbanized Manhattan may have seemed absurd in the early 19th century, in retrospect the gridding exercise doesn’t appear to have gone far enough. Similar exercises could be of use in the rapidly growing cities of the developing world. Not a block-by-block, centrally-planned zoning scheme, but a basic grid with rights of way for arterial roads and parks. In Flint’s words:
The cities of the developing world would do well to take a look at New York City’s grid. There’s going to be a doubling of urban population and a tripling of land area in these cities in the next 30 years, according to Solly Angel, author of Making Room for a Planet of Cities. To accommodate all those millions of people coming in from the countryside, planners are going to have to think big, anticipating large expanses of urban land, planning for infrastructure decades in advance. The framework might make Manhattan’s grid look quaint by comparison; according to Angel, developing-world cities should plan for growth with major arterials one-square-kilometer in size.
Angel’s recommendation for major arterials that are spaced one kilometer apart is based on the notion that anyone living halfway between such roads could easily access public transit on foot. Once the public spaces for roads, parks, and the is defined and enforced, private decisions can motivate the development of the land between. A light-touch approach of this sort may go a long way toward effectively accommodating the inevitable expansion of cities in the developing world.