Sunday, August 2, 2009
I reviewed a research problem statement for the Transportation Research Board Traffic Signal Systems Committee tonight and came across this paper online (see link above) that came up when googling "leaving freeway era". It states: While the jury is still out on the long-range impacts of freeway deconstruction, evidence to date suggests that, on balance, they are positive. Original research reveals substantial capitalization effects. Whether this has been due to the removal of a visual eyesore and public nuisance or the positive effects of a central-city stream and public amenity cannot be assessed from the cross-sectional database used to conduct the analysis. Still, the evidence suggests that the more valuable resource in many large, built-up cities is high quality public space, not transportation accessibility.
Evidence from the United States suggests that following the removal of freeways, most traffic gets redistributed to alternative routes, with public transit absorbing relatively few former freeway travelers. Many discretionary trips are likely not taken once central-city road capacity is removed. Also, the traffic chaos predicted following freeway demolition generally has not materialized, a consequence of operational enhancements, marketing, and transportation demand-management strategies.
It would be wrong to conclude that elevated freeways are increasingly relics of a bygone era. Tampa, Florida, for example, recently opened six-miles of an elevated freeway (three lanes plus a breakdown lane on each side). However, the era of indiscriminate freeway construction and a focus on mobility-based planning is without question over.
Whatever freeways and high-capacity road facilities are built in the future will have to be strategically sited and tied to larger urban development and land-use objectives of the cities and neighborhoods they serve. In this sense, freeway deconstruction is tied to the re-ordering of urban priorities that gives preference to planning for people and neighborhoods, not mobility. Smart growth, high-quality public transit options, bike- and pedestrian-friendly corridors, and improved boulevard designs will no doubt serve to further diminish the necessity for high-capacity elevated freeway structures in many global settings.