There’s a Lot Riding on U.S. DOT’s Definition of 'Congestion'

As the new federal transportation bill, known as MAP-21, moves to the implementation stage, major finding decisions will ride on the nuances by which the U.S. DOT defines and measures "congestion," "roadway performance," and "cost effectiveness".

2 minute read

August 16, 2012, 7:00 AM PDT

By Tanya Snyder


"Congress has done its job, such as it is, and passed a transportation bill. Now it's handed off the policymaking to U.S. DOT, which must issue a raft of rules, definitions, and guidance to accompany the new law, known as MAP-21."

Streetsblog asked economist Joe Cortright for his advice to DOT officials struggling to define congestion. His words of wisdom: "Don't make the mistake the Texas Transportation Institute makes."

"TTI's Urban Mobility Report, released every year, invariably gives top honors to places that have overbuilt road capacity. The institute measures congestion only by looking at the degree to which traffic slows down people's commutes. The problem with that, Cortright says, is that 'you end up rewarding places that encourage people to drive longer and longer distances, and then you look at those long distances that they're traveling, and say because they're moving at a relatively higher speed much of the time that they're driving, that the system is somehow performing better.'"

"Cost-effectiveness also can't be measured without examining what are known as 'externalities' -- the costs of driving that are passed on to the public. 'The existing gasoline tax doesn't even cover the maintenance on the highway system that we have now,' Cortright said. 'It doesn't reflect the economic losses to crashes, it doesn't reflect the economic externalities associated with the environmental effects of burning all this gasoline and putting carbon in the atmosphere, and it doesn't reflect the foreign policy and military costs of being so dependent on foreign oil.'"

"If I were U.S. DOT, I'd try to add in, in figuring cost-effectiveness, the cost of all those other subsidies to automobiles," he added.

Thanks to Tanya Snyder

Wednesday, August 15, 2012 in Streetsblog Capitol Hill

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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