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Congestion effects on the average person (2001).

For more information:
Tim Lomax
979-845-9960
t-lomax@tamu.edu
or
David Schrank
979-845-7323
d-schrank@tamu.edu

Complete details of the 2003 Urban Mobility Report can be found at the website: http://mobility.tamu.edu.

Highway congestion worsens

Traffic solutions and impacts examined
Drivers in the Minnesota transportation system are asked to pay for transportation improvements through taxes and want to know what they are gaining from their investment. The Urban Mobility Study is one of the few studies that provides area-wide estimates and comparisons of urban mobility and congestion. Tim Henkel, director of the Office of Program Management, Minnesota DOT

Despite worsening traffic congestion nationwide, researchers at the Texas Transportation Institute (TTI) in College Station report some encouraging results from the latest Urban Mobility Study.

For the first time, TTI researchers measured the effectiveness of five remedies designed to keep traffic flowing. They included the use of public transportation services, bus and carpool lanes, traffic signal coordination, freeway incident management and ramp meters. According to the research, the analysis of those remedies is providing a clearer understanding of traffic congestion's magnitude and what might fix it.

"Congestion is worsening, no doubt about that, but it would be a much greater problem if not for these and other remedies," says Tim Lomax, who, along with David Schrank, compiled TTI's 2003 Urban Mobility Report.

The 2003 Urban Mobility Report was sponsored by the American Road and Transportation Builders Association's Transportation Development Foundation and the American Public Transportation Association. A consortium of 10 state transportation departments has participated in the methodology enhancements.

Traffic situations were examined in 75 urban areas measuring factors such as hours of travel delay per person and the Travel Time Index — a measure of additional time needed to make a trip during peak travel periods compared to free flow periods. The index has tripled since TTI began collecting data in 1982. A rush hour trip today takes 39 percent longer than a non-rush hour drive, meaning a 20-minute trip during the midday would take almost 28 minutes in the peak.

Illustrating the congestion-reducing effects on the national average 25-minute one-way commute time, the research revealed that a combination of all five remedies reduced the total amount of annual congestion delay per commuter from 58 hours to 50.5 hours.

Large cities aren't the only ones suffering worsening traffic congestion. Smaller cities dealing with growth are also having trouble keeping up with rising transportation demands.

"First of all, the Urban Mobility Report proves we can save a significant amount of time with solutions we now have available, and we can do it at a cost that's very low in comparison to what it costs to build a transportation system," says Lomax. "But even with the widespread use of these cost-effective solutions, we need to add more capacity and manage the demand, as well as seek improvements in land development patterns."

Operational techniques such as ramp meters, incident management and signal coordination help reduce the number of hours stuck in traffic. According to the TTI study, the contribution of these techniques lowered the average annual delay per person from 26 hours to 24 hours in 2001. If all three remedies were implemented on all major roadways in the 75 cities studied, the total travel delay would fall to 22 hours per person — a 15 percent improvement and equal to the traffic delays in 1996.

"This year's study reinforces our belief that the best solution is actually a combination of solutions with cities using their own 'bag of tricks' to fight this growing problem," says Lomax.

"Daily commuters may notice their travel times are becoming more reliable even if the average isn't declining," says David Schrank, who co-authored the Urban Mobility Report. "Had it not been for a handful of those congestion remedies, it would have been much worse."

The Cost of Congestion

The cost of our growing traffic problems is staggering. Drivers wasted 5.7 billion gallons of fuel, or about 42 gallons per person, in the 75 areas studied. Annually, 3.5 billion hours of extra travel time can be blamed on traffic congestion. The total cost of congestion has risen to nearly $70 billion, a rise of $4.5 billion more than the previous year.

On a personal level, the average cost per person in the 75 cities studied was $520, up about $5 from the previous study. The cost averages ranged from $650 per person in areas with populations greater than 3 million to $130 per person in smaller towns.

Improving Driving Conditions

So how will the congestion study help improve driving conditions in Texas? The Texas Department of Transportation (TxDOT) funded an additional study to develop what is called the Texas Congestion Index (TCI). Working with staff from TxDOT and metropolitan planning organizations, TTI researchers developed the TCI to assist in evaluating the impact of alternative transportation improvements.

"The TCI will be a key planning tool in our urban planning process," says David Casteel, TxDOT's San Antonio district engineer. "The congestion index is more inclusive of other modes of transportation and more robust for use in 'what-if' analysis while considering corridor planning." As it is adapted to the TCI formula, the congestion study will become a key planning and public involvement tool, Casteel says.

Monitoring the Transportation System

The Minnesota Department of Transportation (Mn/DOT) uses the Urban Mobility Study as a way to measure, monitor and communicate the performance of their transportation system.

"Drivers in the Minnesota transportation system are asked to pay for transportation improvements through taxes and want to know what they are gaining from their investment," says Tim Henkel, director of the Office of Program Management at Minnesota DOT. "The Urban Mobility Study is one of the few studies that provides area-wide estimates and comparisons of urban mobility and congestion."

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