AASHTO Journal, 8 February 2013
Congestion on our nation’s transportation infrastructure costs each commuter about $818 per year, according to a report released Tuesday by the Texas A&M Transportation Institute (TTI). That adds up to $121 billion per year nationally.
TTI’s “2012 Urban Mobility Report” highlights the cities that experience the most congestion, finding that Washington, D.C.; Los Angeles; San Francisco/Oakland; New York/Newark; Boston; Houston; Atlanta, Chicago; Philadelphia; and Seattle made up the top 10 list of the nation’s most congested cities.
Authors of the report this year introduced a new measure called Planning Time Index (PTI), which helps determine travel reliability by showing the amount of extra time needed to arrive on time for big events, such as getting to the airport for a flight, important shipments, and medical appointments. For example, a 3.0 PTI for a trip means an individual should allow 60 minutes to ensure arriving on time for a trip that should take 20 minutes when there is little traffic. For the most congested city (D.C.), TTI found a PTI of 5.72, meaning a commuter would need to plan on almost three hours to be certain of arriving on time at the end of a journey that might take only a half hour if traffic is light.
“We understand that trips take longer in rush hour, but for really important appointments, we have to allow increasingly more time to ensure an on-time arrival,” said Bill Eisele, co-author of the report, in a statement. “As bad as traffic jams are, it’s even more frustrating that you can’t depend on traffic jams being consistent from day-to-day. This unreliable travel is costly for commuters and truck drivers moving goods.”
Environmental concerns also grow along with the economic problems of congestion. TTI estimates that 56 billion pounds of additional carbon dioxide were emitted because of traffic congestion in 2011, or 380 pounds per driver. About 2.9 billion gallons of fuel were wasted during that period, which TTI compares to filling the New Orleans Superdome four times (a number which is the same as 2010, but down from 2005’s 3.2 billion).
Other findings by TTI regarding the effects of congestion include:
- 5.5 billion hours of total time wasted due to congestion
- The average commuter spent 38 extra hours traveling in 2011
- 22 percent of the delay cost comes from the effect of congestion on truck operations (not including value for the goods transported in those trucks)