Patrick Lamson-Hall, Research Scholar at the New York University Stern Urban Expansion Initiative, joined us for an IDFC-U discussion on "The Coming Billions: Making Room for Urban Expansion."
Lamson-Hall drew on the experiences of the Urban Expansion Initiative to help expanding cities make room for rapid growth. The initiative has been active in countries including Colombia, Ethiopia, Ecuador, Mexico. NYU has recently partnered with IDFC Institute to launch an India Urban Expansion Initiative.
Lamson-Hall explained that urban population densities have shown a declining trend worldwide – this means that while urban populations are growing, they are increasingly occupying more space per person. This trend can be construed positively, as it is indicative of rising wealth and better access to transport. India has over 100 cities that are growing at over 3% per year in population terms, which means their urban residents will double in 20 years. So, when Indian cities plan for growth, they should account for not only a rapid population increase, but an even greater spatial expansion.
Lamson-Hall argued that population containment strategies have not worked well in the past, and instead, we should follow the “making room” paradigm to address inevitable urban growth. This paradigm is framed by four propositions:
- The inevitable expansion proposition, which holds that cities will expand in the coming years regardless of efforts to control them, and containment is neither possible or desirable
- The sustainable densities proposition, which recognises density as a market outcome that reflects the amount of space people can afford to consume, and which holds that planners can influence the amount of space that is available on the market
- The decent housing proposition, which holds that making land more affordable and abundant will make housing more affordable
- The public works proposition, which supports that cities need to secure land for public space before development happens
To plan for such urban expansion, Lamson-Hall said that accurate maps, generous city limits, a network of arterial roads, and a hierarchy of public open spaces are necessary preconditions. Further, the roads are encouraged to be built on a one kilometer by one kilometre grid. Advantages of this include the fact that such a grid will occupy no more than five percent of the expansion area, and assuming there is a normal street layout within these blocks, no resident will be more than 15 minutes walking distance from one of these roads.
He also referred to visionary plans in Barcelona and New York to acquire the rights of way for grid road networks before the city expanded. In New York, for instance, three commissioners made provisions for Manhattan’s grid road network in 1811, when the city was developed on only the southernmost tip on an area of about four square kilometres. It expanded the buildable area of the city seven-fold, and it was estimated then that the city would take about 500 years to stretch to the top of Manhattan. The city in fact took only about 80 years to do so, and several subsequent plans expanded this grid network. Lamson-Hall acknowledged that not every city could guarantee success, simply by copying another city’s example. Yet it seems to hold that when planning for growth, it is safer to err on the side of caution, especially in cities where the land is relatively inexpensive and displacement of people in the expansion area can be minimised and delayed until the city grows into the planned area.
Patrick Lamson-Hall is a Research Scholar at NYU Marron Institute of Urban Management. He is an urban planner and development professional working at the NYU Urban Expansion Program at the NYU Marron Institute and Stern School of Business.