2009 URBAN MOBILITY REPORT: Six Congestion Reduction Strategies and Their Effects on Mobility

The Urban Mobility Report procedures give estimates of mobility at the area-wide level, describing congestion consistently by using generally available data and allowing for comparisons across urban areas or groups of such areas. The report procedures focus not only on projects that added lanes or reduced demand, but also on several other operational treatments and public transportation services. The report describes a framework for incorporating the operational treatments and shows the resulting effects. The following six congestion reduction strategies were tested in 90 urban areas. Overall, these strategies lowered the freeway travel time index and freeway or arterial hours of delay:

• Freeway entrance ramp metering.
• Traffic signal coordination.
• Incident management programs.
• Access management programs.
• High-occupancy vehicle (HOV) lanes.
• Public transportation.

This analysis estimates the benefits that certain operational strategies provide at an urban-area level. Because each urban area in the study has different characteristics, some strategies may be more viable in one area than another. Additionally, the deployment of the individual operational strategies is done at different levels in each urban area, and this can lead to very different overall results when doing comparisons. For years, the annual Urban Mobility Report statistics showed that traffic congestion has increased each year. However, it has emphasized that urban areas must use every possible treatment available to try to slow or stop this growth. The figures in the report show that certain studied operational treatments are making a significant impact to reduce area-wide traffic congestion.