By the Numbers, U.S. Traffic Congestion Worse Than Ever

COLLEGE STATION, Texas, May 10, 2005 (ENS) - Traffic congestion continues to thicken across the United States, costing Americans $63.1 billion a year, according to the latest annual traffic study of 85 urban areas by the Texas Transportation Institute. Released Monday, the 2005 Urban Mobility Report measures traffic congestion trends from 1982 to 2003, reflecting the most recent data available.

Drivers in large, medium and small cities all experienced more severe congestion lasting a longer period of time and affecting more of the transportation network in 2003 than in the baseline year of 1982, this year's study shows. In 2003, the total amount of delay reached 3.7 billion hours, and 2.3 billion gallons of fuel were lost as engines sat idling in traffic jams.

In 1982 a motorist driving at the peak periods sat in traffic an average of 16 hours during the entire year. In 2003, that person sat in traffic for 47 hours, nearly three times as long.

In very large urban areas with more than three million people, the Los Angeles-Long Beach-Santa Ana area of California is the most congested, with the San Francisco-Oakland area not far behind.

Washington, DC is in third place, Atlanta, Georgia is the fourth most congested very large urban area, and Houston, Texas is fifth, the study shows.


Rush hour traffic in the Houston, Texas urban area (Photo courtesy TTI)
Congestion occurs during longer portions of the day and delays more travelers and goods than ever before, the study shows. And congestion is more severe in larger urban areas.

If the current fuel prices are used, what the researchers call "the congestion invoice" climbs another $1.7 billion, which would bring the total cost to about $65 billion.

The invoice considers the value of extra travel time and the extra fuel consumed by vehicles traveling at slower speeds. Travel time has a value of $13.75 per person-hour and $72.65 per truck-hour in 2003. Fuel cost per gallon is the average price for each state.

"Congestion is a complicated issue and canít be solved with one approach nationwide," says study author Tim Lomax, a research engineer at the Texas Transportation Institute (TTI). "We need to think about how policies and programs enacted at the federal, state and local levels affect congestion."

Despite slow growth in jobs and travel, urban areas are not adding enough capacity, improving operations or managing demand well enough to keep traffic congestion from growing larger, the study shows.

Lomax and co-author David Schrank found that the number of urban areas with more than 20 hours of annual delay per peak traveler has grown from only five in 1982 to 51 in 2003.

Over the most recent three years, the contribution of operations improvements has grown from 260 to 340 million hours of congestion relief, but delay has increased by 300 million hours over the same period.

The study comes at a time when Congress is considering legislation to re-authorize funding for transportation programs and projects across the nation. The House passed a version of the six-year bill that includes a Congestion Relief Program to address urban congestion problems.

"The bill includes important sections dedicated to developing a strategy to improve mobility by attacking congestion in a systematic way using an array of traffic congestion relief activities," says Lomax.

Building more road and public transportation capacity, operating that capacity for the most efficient service, and innovative pricing and truck-only lane projects are among the relief measures authorized by the House bill, known as the Transportation Equity Act: A Legacy for Users. The bill has been placed on the Calendar in the Senate.


Delays that waste time and fuel are more frequent and last longer than before. (Photo courtesy TTI)
"There is no single solution that can reverse the growth in congestion," Lomax says. "The deliberations in Congress, decisions by state and local elected officials, the results of voter initiatives last fall, and our research findings recognize that reality."

The study shows that regular route public transportation service on buses and trains provides a significant amount of peak period travel in the most congested corridors and urban areas.

If public transportation service was discontinued and the riders traveled in private vehicles, the 85 urban areas studied would have suffered an additional 1.1 billion hours of delay in 2003. That figure represents a 27 percent increase in delay and an additional congestion cost of $18 billion.

Useful solutions to delay shown by the study include high-occupancy vehicle lanes - also known as diamond lanes, bus and carpool lanes, or transitways. Data for the 19 congested corridors studied showed a saving equivalent to 10 to 15 years worth of congestion growth in the average area. "These HOV lanes carry one-third of the peak direction passenger load, providing significant passenger movement at much higher speeds and with more reliable travel times than the congested mainlanes," the study says.

Entrance ramp meters that regulate the flow of traffic on freeway entrance ramps using traffic signals are another useful solution. Designed to create more space between entering vehicles so those vehicles do not disrupt the mainlane traffic flow, the signals allow one vehicle to enter the freeway every two to five seconds. They also reduce the number of entering vehicles due to the short distance trips that are encouraged to use the parallel streets to avoid the ramp wait time.

Twenty-five of the urban areas reported ramp metering on some portion of their freeway system in 2003 for a total of 33 percent of the freeway miles. The effect was to reduce delay by 102 million person hours, approximately five percent of the freeway delay in those areas.

Also useful in reducing delays are the freeway incident management programs - such as Freeway Service Patrol, Highway Angel, Highway Helper, The Minutemen and Motorists Assistance Patrol - that attempt to remove crashed and disabled vehicles from the freeway lanes and shoulders by working in conjunction with surveillance cameras, cell phone and reported incident call-in programs.


Another accident slows traffic on a California roadway. (Photo courtesy Rialto Police Department)
In the 71 areas studied that have such programs, the effect was to reduce delay by 177 million person hours, approximately seven percent of the freeway delay in those areas.

Other helpful strategies are traffic signal coordination and arterial street access management.

The data suggest that nine percent of the roadway delay is being addressed by these four operational treatments for a total of 336 million hours in 2003, Lomax and Schrank report. And if these treatments were deployed on all major freeways and streets, the benefit would expand to about 15 percent of delay.

The authors point out that these techniques can be enacted much more quickly than major roadway or public transportation system expansions can occur. "But the operational treatments do not replace the need for those expansions," they say.

"Congestion is a complicated issue and canít be solved with one approach nationwide," Lomax says, "We need to think about how policies and programs enacted at the federal, state and local levels affect congestion."

View the full "2005 Urban Mobility Report" online at: