I want you to spend some time looking at the graph below:
It shows the relationship between patterns of development and fuel use. Unsurprisingly, compact places like Hong Kong have a far lower per capita consumption than places that sprawl, such as cities in the USA. London sits in the ‘sweet spot’, just at the point before exponential growth in consumption takes off.
Now lets look at some data on CO2:
The correlation between car use, fuel consumption and CO2 is pretty clear (although other factors skew it a bit). Density has a strong role to play in reducing emissions, and it does this mainly through reducing the need to travel. Yet there is strong resistance to making places more dense. 30 dph seems to be about all people are willing to accept and this is laying the groundwork for all kinds of future issues.
Next, lets look at connectivity. Research by Saelen et al (2004) concludes ‘that residents from communities with higher density, greater connectivity, and more land use mix report higher rates of walking/cycling for utilitarian purposes than low-density, poorly connected, and single land use neighborhoods’. There is a wealth of research that shows the importance of the urban environment to health, and it is no surprise that better connected places are more walkable.
Connected, populated places offer the best chance of supporting a mix of uses as well as buses and other services, and we need a shift away from fearing density if we are going to deliver sustainable development on the ground.