California Partners for Advanced Transportation Technology

This report focuses on traffic congestion under current road conditions with the objective of developing a quantitative understanding of their costs. The work is intended to provide a foundation upon which to build later estimates of the benefits that could be attributable to the use of Intelligent Vehicle Highway Systems (IVHS) technologies. The report gives an overview of traffic congestion and summarizes the principal sources of research in the areas of quantifying the costs of congestion. It reviews this past work relative to the usage of data, methodological approaches used in the analysis, and assumptions, as well as the California State Department's methods for quantifying congestion at the individual district level.