Building Design - 22 October 2020
Low-traffic neighbourhoods might sound like a good idea, but we should be wary of just jumping on the bandwagon, David Rudlin writes
When I was a planning officer in Manchester in the 1980s, my patch included Moss Side. It is a neighbourhood of two halves.
On one side is the Alexandra Park estate, built in the 1970s, and on the other the Victorian terraced streets north of Manchester City's old Maine Road football ground.
Back in the 80s, a few years after the riots, neither was quite as bad as their reputations suggested. But they were not far off. As planning officers, we were told to do site visits in pairs.
Part of the problem was that the streets were a maze of dead ends. The Alex Park estate had been designed from the outset on Radburn principles, but the terraced streets had also been retrofitted to achieve the same effect.
Roads were blocked off so that, away from the main streets, there was no way through by car. It was what we would today call a low-traffic neighbourhood or "mini Holland".
In Moss Side this was a disaster. Gangs of kids on bikes could disappear into the area where the police could not follow. Pretty soon no one who did not live there would go into the neighbourhood, reinforcing the sense of it being a no-go zone. Of course, levels of car ownership at the time were low, the issue was more to do with joyriding.
The Alex Park estate was subsequently de-Radburned based on a masterplan by the much-missed MBLC Architects, the first practice I remember to call themselves "urbanists". Their plan cut roads through the estate, turned the housing around so that it faced on to these roads and opened up the whole area to traffic. Meanwhile all the Victorian terraced streets were also reopened.
The subsequent transformation of both areas has been extraordinary. I am not claiming this can be solely attributed to reopening the roads, but that played a major part.
Because of this I have always believed that permeability, as we urban designers call it, needs to relate to cars as well as pedestrians and bicycles, something that is directly challenged by the mini-Holland concept.
It might be counter-intuitive to suggest that the presence of through traffic on a road makes it feel safer for pedestrians, but that has certainly been my personal experience.
In this respect I often reference the work of Bill Hillier in the 1990s. He looked at the number of people on the street in estates where there was no through traffic.
He wrote that "the daytime encounter fields in estates turns out to be like the night-time in ordinary urban streets. In terms of their naturally available encounter fields, people on these estates live in a kind of perpetual night".
So in what way are low-traffic neighbourhoods different to Radburn or indeed cul-de-sac based layouts? The assumption seems to be that making cars go a bit farther will persuade people to leave them at home, not that this has ever seemed to work with cul-de-sacs.
In 2008 the BBC made a fascinating series called Britain from Above, presented by Andrew Marr. The sequence that I always remember was a GPS trace of 380 London taxis over the course of a day.
This showed them sticking to the primary routes throughout most of the day but, as congestion built up during rush hour, there came a moment when all the taxis switched to the minor streets. This is what The Knowledge allows taxi drivers to do.
In one respect this is an example of resilience; the way that "permeable" cities like London are able to flex and absorb traffic pressures. The problem is that satnavs now give us all the same knowledge as the taxi drivers.
Traffic levels on minor streets have risen hugely as satnavs seek out alternative routes to avoid congestion. I can see how low traffic neighbourhoods are a reasonable response to this.
The problem, of course, is that removing the safety valve worsens congestion on the primary streets. Indeed it is probably the inconvenience of congestion rather than the extra distance to travel that persuades people to leave their car at home.
Despite Moss Side being bisected by Manchester's main commuter route from the south, this does not seem to be a problem. Because the traffic is heading to the city centre, there is little to be gained from diverting through the streets of Moss Side.
A solution that works in one place may not work or be necessary elsewhere. Low traffic networks may be a good idea - indeed, who can argue with a policy to promote walking and cycling at the expense of the car? But, as with all these things, we need to be careful before jumping uncritically on bandwagons. We need to consider the consequences.
- David Rudlin