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Choices Key to Relieving Commuter Misery

New Index Integrates Congestion and Transit Data
 for More Complete Commuting Picture

Washington, D.C. (May 7, 2001) --- A groundbreaking analysis of newly released data shows that road building has done little to ease congestion, while transit service is significantly lessening the burden of congestion on many commuters.  A new ranking developed by the Surface Transportation Policy Project shows how the average commuter is affected by both congestion levels and the availability of transit in 68 U.S. cities.

“The misery inflicted by traffic congestion is not the same everywhere,” said Roy Kienitz, Executive Director of STPP.  “The places where commuters suffer most are the ones with the fewest transportation choices.”

STPP analyzed data collected by the Texas Transportation Institute for its annual Urban Mobility Study and found that metro areas that added the most roads have had little success in easing congestion.  But metro areas with good transit service rank significantly lower on the new Congestion Burden Index.

The Congestion Burden Index, developed by STPP, measures both the severity of traffic congestion and the degree to which commuters are exposed to it.  The new index combines TTI's measure of rush-hour congestion with federal data showing the portion of commuters who are driving to work and are therefore exposed to congestion.

According to the Congestion Burden Index, Los Angeles maintains its number-one ranking because its residents suffer from both major congestion and relatively few ways to avoid it.  However, San Francisco, which has the second-worst rush-hour congestion as measured by TTI, also has almost 500,000 citizens traveling to work by means other than driving.  This puts it 29^th in the Congestion Burden Index.   While TTI gives Boston and Atlanta similar scores for rush hour congestion, Atlantans suffer more due to congestion because a higher share of them drive to work.  As a result, Atlanta ranks 6^th in the Congestion Burden Index while Boston ranks 47^th.   The Congestion Burden Index is available for all 68 metro areas surveyed by TTI.

Traditionally, transportation agencies have responded to congestion by adding to the road system. However, STPP's analysis finds that the places adding roads most aggressively over the past 10 years have had no greater success in fighting congestion than those not adding roads.  In the 23 metro areas that added the most to their road systems, road space per person increased by 17 percent.  In the 23 places that added the least to their road systems, road space per person actually fell by 13 percent.  Yet both congestion levels and growth in congestion over time were essentially the same in the two sets of metro areas.  The two sets also experienced similar population growth over the 10-year period studied. 

Many Americans have already decided on their own to fight congestion by turning to transit.  Recently released figures show that over the past five years transit use has grown by 21 percent while driving has increased only 11 percent. This is a dramatic turnaround from the early 1990's when driving grew steadily as ridership on trains and buses fell.

“People are searching for alternatives to driving in rush-hour traffic and increasingly they are choosing bikes, buses, subways, and other options,” said Kienitz. 

Quality transit service makes a big difference in allowing more people to avoid driving to work.  STPP's analysis shows that the places with the best transit service, as measured by the Transportation Choice Ratio, are also the places where the smallest portion the workforce drives to work.  This shows that efforts to provide transit at the local level are delivering a direct payoff to commuters.

One of the reasons road-building shows disappointing results in easing congestion is that adding road capacity doesn't just meet the current travel demand: it actually spurs additional driving. When a road is widened, more people will choose to drive on it — by either switching from another route, time of day, or mode, or by taking additional trips. Transportation planners call this “induced travel.” 

The Surface Transportation Policy Project is a nationwide network of hundreds of organizations, including planners, community development organizations and public interest groups, devoted to improving the nation’s transportation system. 

Metro area fact sheets with additional data on commuting patterns, congestion rankings, and road capacity are available at STPP's website, http://www.transact.org.  A full copy of the report can also be found at the website.  Local experts are available for comment. For more information, call Barbara McCann at (202) 466-2636.