Closer examination of development and building within all our world cities (including the US cities) reveals a rich mixture of urban forms and a great many districts with different characters and a vast mix of commercial, retail, visitor and other uses. All human life is there and the best cities are noticeable for having a wide variety of districts, all catering for a wide range of different occupants.
The development of surrounding natural land as city or suburbs is most common in the emerging economics of the new world. A few cities, such as Shanghai and Dubai, are still expanding into surrounding countryside and desert.
Some cities, notably Shanghai and Moscow, have demolished significant swathes of the city to build new sectors. Tokyo also has a high rebuild rate but at an individual plot level, as does Hong Kong.
Some cities are so land-constrained that they have created it by forming islands or an extended shoreline in the sea. This type of expensive development is found most frequently in ‘new world’ cities such as Hong Kong, Dubai and Singapore, but has also taken place in older Asian cities such as Tokyo, and we even found early 20th century examples of island-making in Miami.
The story in most old, established cities in Europe and the US is of an extensive and fully developed urban landscape offering limited opportunity restricted by planning policy, for physical expansion. Economic development, therefore, depends on the effective use and reuse of existing land supply.
We see in almost every case where land is constrained that old industrial land is being reused. London’s old docks in the east and its disused manufacturing sites in the outer boroughs are good examples of this type of redevelopment and regeneration, but this can be capital intensive and costly, especially when infrastructure projects, such as roads, transit and decontamination, are needed to open up these sites for public use.
Four of our world cities – Sydney, London, Rio and Tokyo – have either had or will have an injection of public money for regeneration projects by hosting the Olympic Games in the recent past or future. This can, and has, been the catalyst for infrastructure projects that these cities need and has or will open up new areas for more intensive urban development.
World cities have responded to restrictions on sprawling development by re-using and reinventing existing run-down neighbourhoods and districts. Economic regeneration is often led by creative people: artists, designers and tech entrepreneurs who agglomerate in a cheap, run-down city sector, attracted by low rents. When successful, many of these districts become reinvigorated, with more jobs and higher economic activity.
Another response to limited land supply is to both preserve what is already in place and re-use and intensify its use, recreating it as a visitor attraction and economic generator. The conservation and preservation of old buildings and city districts is often organised at a city level (or international level in the case of World Heritage sites).
It goes against the short-term consequences of land price inflation and resists high bid rents for the longer-term legacy of historic quarters. Perhaps an unintended consequence is that this has helped create some of the highest value areas, as this legacy is valued by visitors and occupants and eventually becomes monetised.