Denver-area commuters spent slightly less time in traffic in 2009 compared with the previous year, according to a ranking of the nation’s most congested metropolitan areas.
The Texas Transportation Institute’s Urban Mobility Report, released Thursday, shows metro Denver commuters endured an average of 47 extra hours in traffic in 2009, the most recent year studied, compared with 48 hours in 2008.
Each year, TTI uses the measure of “Yearly Delay per Auto Commuter” to assess congestion in hundreds of urban areas across the country.
For 2009, the Chicago and Washington, D.C., areas tied as the communities with the worst congestion, with commuters spending an average of 70 extra hours in traffic.
The metro areas of Los Angeles, Houston and San Francisco-Oakland rounded out the top five among most congested. Metro Denver was in ninth place overall and second-worst among urban areas sized between 1 million and 3 million people — after Baltimore.
TTI offered some recommendations to reduce congestion nationwide, including:
• Quickly removing vehicles involved in accidents, timing traffic signals better, and improving the designs of roads and intersections.
• Adding new highway lanes where appropriate.
• Using flexible work hours and other techniques to move commuters outside traditional rush-hour periods.
• Encourage denser mixed-use commercial and residential development “so that more people can walk, bike or take transit to more, and closer, destinations.
The Texas transportation group also prepares a “travel time index” for each urban area that compares travel time at rush hour with off-peak free-flowing conditions.
Metro Denver’s travel-time index shows that a typical 30-minute off-peak commute would take an average of slightly less than 37 minutes at rush hour — a 22 percent increase, according to TTI’s analysis.
The Los Angeles area had the worst imbalance between peak and off-peak travel times among urban areas in 2009, TTI found, with L.A. commuters spending about 38 percent more time on the road at rush hour, compared with free-flow periods of the day.
Some organizations challenged TTI’s methodology in the study.
The travel-time index is built on the “unrealistic” assumption “that travel times should (and could) be no longer during peak periods as during non-peak periods,” according to a critique of TTI’s work by the group CEOs for Cities, which calls itself a “civic lab” for urban leaders that aims to “advance the next generation of great American cities.”
Reliance on the index also “obscures the effect of land-use patterns in creating longer travel distances,” CEOs for Cities said.
“Sprawling development, not traffic delays, is the principal source of variations in travel-time differences among metropolitan areas,” the group said.
Jeffrey Leib: 303-954-1645 or jleib@denverpost.com
