Jarrett Walker

Transit role in sprawl repair

International consultant in public transit design, Nov 22, 10.

Tagged with transit, sprawl, planning, smart growth, development

Duany Plater-Zyberk, one of the leading planning firms associated with New Urbanism, is thinking about “sprawl repair,” a process by which utterly car-dependent landscapes could be transformed into something more walkable, and thus more resilient. Galina Tachieva of DPZ has an article explaining the concept at Planetizen.

The only valid option is to repair sprawl – to deal with it straight on, by finding ways to reuse and reorganize as much of it as possible into complete, livable, robust communities. Pragmatism calls for the repair of sprawl through redevelopment that creates viable human settlements, places that are walkable, with mixed uses and transportation options.

As examples, Tachieva suggests turning a shopping mall into a complete mixed use town center, or dropping townhouses into the spaces between McMansions.

The ideas she presents are exclusively about the development parcel, not the street. Clearly, though, such urbanized places will have dramatically different transport needs, which will also require re-thinking the standard suburban arterial. And since government has much more direct control over the street than over the development parcels, we might move faster on sprawl repair if we focused on the arterial first, or at least at the same time. Last month, on a speaking tour that took me to Portland, Fresno and Los Angeles, I spent some time thinking about this issue.

The densified sprawl that DPZ envisions will clearly be a place that needs much more effective transit. Parking will be more scarce, and density will be higher, so there will need to be more transport options. While cycling will take up some of that need, transit is still the most versatile sustainable transport mode for longer trips, the only one capable of delivering you from one place to another as a pedestrian, unencumbered by a vehicle. And the only place to put that transit, in a classic sprawl landscape, is on that huge, government-controlled arterial.

As I first discussed here, the ideal geography for transit is to have a series of transit destinations (dense housing, mixed use, jobs, activities, etc) located in what feels like a straight line, so that a transit line can connect all these points in a way that feels like a direct route between any two points. The key challenge is to avoid slowing down or deviating too much to serve the intermediate points, as this makes the intermediate points feel like obstacles to anyone whose trip requires riding through them.

The classic suburban commercial arterial already does that, up to a point. It gathers development around it without letting that development slow it down. So we should be looking for ways to capture this virtue for transit. A process of “sprawl repair” should start, perhaps, with a series of steps aimed at repairing the arterial, starting with the realisation that the arterial’s straightness and speed become an asset if transit can operate reliably.

Fresno is an interesting example because it’s at a stage where it could look at what’s happened to bigger sprawl-cities and choose another path….

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Source: Human Transit, November 15, 2010

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