Encouraging Sustainable Cities Chris Hamnett Professor of Geography, King’s College London

Changing behaviour or urban form? how do we encourage sustainable or green cities? This is not simply a matter of trying to encourage citizens to engage in more sustainable practices in their daily lives. The issues, and solutions, cannot simply be addressed by trying to encourage changes in individual behaviour important though this is. It is necessary to change urban form and the structure of cities which generate behaviours.

Changing systems or individuals Individual behaviour takes place within the context of existing urban structures which both prevent and encourage or even compel certain forms of behaviour. Two simple examples: Swimming is a healthy activity, but impossible to get people to swim if there ar no swimming pools, or they are far away or very expensive. No public transport use if no public transport.

Exhortation/Compulsion not enough My key point is that people cannot be forced or encouraged to develop greener behaviours if such behaviours are not physically possible or extremely expensive or time consuming. People need to be encouraged to develop key alternative behaviours by making it sensible and attractive to do so. If we want encourage people to use rubbish/garbage bins we have to provide them. No provision = no use.

Supply shapes Behaviour This is a very important point. We cannot seek to change individual or household behaviour in the absence of good alternative solutions. If you want people to recycle household rubbish then it is important to provide recycling bins or bags to allow them to do this easily. No bins = no recycling despite the advertisements and pleas on TV and the media. Supply influences and may even shape behaviour.

The problem of modifying behaviour It is possible to try to change/modify individual behaviour in a number of ways. These range from what is known as ‘nudging’ or incentives through to disincentives or charges for certain practices through to hard disincentives and fines. Examples of disincentives include the London congestion charge of £10 per day per car to enter central London or the Beijing 4 days of 5 rule for private cars to drive. Incentives include bicycles.

Encouraging green behaviour The Dutch have always used bikes in towns. The French started pblic provision of bikes in Paris with the velo libre scheme to allow users to rent abike anywhere in the city and return elsewhere This was taken up in London in similar scheme. These bikes have now become very popular with younger age groups where car use is declining.

The importance of urban form The most important point about production of sustainable or green cities is the underlying urban form or structure must allow/encourage green behaviour. It is accepted that large scale car ownership is not sustainable and generates congestion and large scale pollution if the cars are not electric. But to avoid using cars people must have convenient, accessible and affordable public transit solutions. If there is no or poor public transit you cannot ask people to use it. Behaviour is shaped by supply.

The importance of public transit My wife and I have two cars but neither of us would dream of driving into central London, except perhaps in the evening for a concert or on a Sunday. The reasons are simple. Travel to central London by car generally takes longer than public transit, it is much more expensive in terms of parking and congestion charges and it is difficult to find anywhere to park. It is easy and convenient to use public transport. So, how do we enourage/foster public transit?

Urban form, density and public transit. Which cities have a good public transit system – the answer, put simply, is older, high density cities where much of most of the housing is in the form of terraced/row housing/ apartment blocks. Low density cities/suburbs consisting of detached single family housing at maybe 4 dwellings to the acre or lower density do not provide a high enough population density to make public transit subway systems effective.

A question? The next 5 slides show public transit systems for several major world cities. The question is which is the odd one out, and why? Answer is self apparent. But why should we design cities on this model, when there are much better models to use?

Not the Los Angeles model The point about the last two slides is that LA is seen as the capital of car in part because it has no public subway system. It had a very good tram system but it was taken up in the 1930s. If we want people to user green transport we need to provide it for them. People cannot use bikes if there are only freeways and no bike lanes. Then we can encourage them to use it.

High density need not equal high rise I have argued that high density is important for good, efficient and economic public transit systems. But high density does not necessarily imply high rise. It’s possible to get high density by good spatial layouts as Leslie March and Martin the architects showed 40 years ago. The clearest example is that of central Paris or other European cities such as Milan, Madrid. But low density suburban sprawl is not green.

Supply green solutions to help change peoples behaviour My message is very simple. Let us encourage people to change their behaviour to help the shift to greener cities but they cannot do this in isolation. If we want people to recycle more we have to make it easy and convenient for them to do so. Exhortation alone not enough. Most boroughs in London provide easy to use recycling bins and regular weekly collections.