Saturday, June 13 2015 @ 10:35 PM UTC
Contributed by: B' Spokes
The main reason, Turner has found, is simple adding road capacity spurs people to drive more miles, either by taking more trips by car or taking longer trips than they otherwise would have. He and University of Pennsylvania economist Gilles Duranton call this the "fundamental rule" of road congestion (The Fundamental Law of Road Congestion: Evidence from US cities: http://bit.ly/1Hevghc): adding road capacity just increases the total number of miles traveled by all vehicles.
In an influential 2011 paper, they looked at the total capacity of highways in each metropolitan area in the US and compared it with the total number of vehicle miles traveled. They found a one-to-one correlation: the more highway capacity a metro area had, the more miles its vehicles traveled on them. A 10 percent increase in capacity, for instance, meant a 10 percent increase in vehicle miles, on average. [http://bit.ly/1S6NEBa]
from CenterLines, the e-newsletter of the National Center for Bicycling & Walking.
[B' Spokes: What ever mode of transportation gets the most support gets used the most. That should be fairly obvious by now.]