Rethinking urban spatial barricades

Planning, 27 June 2008

At the edges of nearly all the world's cities and also often at their centres are tracts of unplanned settlements. Labelled as slums, favelas and shanty towns, these places have been made largely without the intervention of planning. Their numbers are increasing as the planet moves from the field to the street and urban populations reproduce.

Self-established and built without the basic infrastructure of water and electricity supply, it is hardly surprising that such settlements harbour profound social and economic problems, visible through the poverty that covers most. The differences between the towns and cities of history and today's unplanned settlements include the unprecedented pace of change and social and political resistance to the integration of these new people. Many informal places are made up of populations ejected from established urbanity.

State planners have an unerring ability to translate political resistance into social division by physical and spatial means. Thus unplanned settlements are often wrapped by a cordon sanitaire - planned green swathes that separate the haves from the have-littles or a motorway dividing the established centre from the informal edge. Once built, these barriers are hard to breach.

It is in the occasional absence of such a physical or spatial divide that the reality of unplanned settlements is clearest. This is vividly illustrated in a photograph shown at the Venice Biennale of tin shacks in a shanty town abutting the luxury high-rise condominium block with a swimming pool on each balcony.

Perhaps the most intriguing aspect of this global phenomenon is the emergence of certain unplanned settlements as valued centres. Seemingly against the odds, many have established themselves as local economies with stable social structures and some have thrived. Two parts of the same city occupied by populations of similar origins can chart very different courses when it comes to the generation of social and economic capital.

Understanding the factors that contribute to the success of certain places and the failure of others is an important academic and professional pursuit that offers hope to the current and future residents of such places and to the municipalities charged with managing them.

In my experience, a first important step is to try to change the mindset of politicians and planners. It is too simple to view unplanned settlements as slums that need replacing. The comprehensive clearance tactic has provoked violence, which should alert most authorities to the need for an alternative solution.

Planners can play a new and different role to that of barricade builder. Careful analysis of the physical and spatial fabric of unplanned settlements can identify opportunities to retain and improve parts while removing and replacing others. A central factor in the success of historic urban places is a balance of global and local movement patterns and informal places are no different.

Linking the edge of a city to its centre, and its edge to its edge, is a key way to achieve this and cannot simply be resolved by crude road building programmes. Instead, it needs to be achieved with paths linking the foot-based movement of the local residential marketplace with the foot-based movement of the central business district.

- Tim Stonor is managing director at Space Syntax Ltd.