This study is a review of current practices in 13 states to: (1) measure traffic congestion and its costs; and (2) manage congestion with programs and techniques that do not involve the building of new highway capacity. In regard to the measures of congestion, the findings suggest two broad conclusions: (a) the most popular measures are not LOS or volume to capacity ratios; but rather the direct measures of either average time to traverse the distance between two points, or the average speed of vehicles. These are sometimes used to construct estimates of delay during peak traffic periods. (b) Five of the 13 states are either using or trying to devise more complex measures of congestion, measures that include estimates of the various costs associated with congestion. Regarding congestion management, most of the 13 states are implementing the 10 congestion management techniques identified by the study. When asked to rank the most effective techniques, the top four were incident management programs, signal coordination, traffic management centers, and access management.

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The contents of this report reflect the views of the authors, who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky or the Kentucky Transportation Center. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names or trade names is for identification purposes only and is not to be considered an endorsement.