Review of U.S. Department of Transportation Truck Size and Weight Study: First Report: Review of Desk Scans

The Committee for Review of U.S. Department of Transportation (USDOT) Truck Size and Weight Study has released its first of two reports. The Review of Desk Scans letter report reviews five preliminary products of the study of truck size and weight limits that the 2012 surface transportation authorization statute requires USDOT to carry out. The five preliminary products of the study, called desk scans, are surveys of past research and analysis methods for estimating the effects of changes in truck size and weight limits in each of five areas: bridges, pavements, truck and rail shares of freight traffic, safety, and enforcement of truck regulations.

The committee that produced the report recommends that USDOT continue the work begun in the desk scans by including two kinds of synthesis in its final report: first, a synthesis of experience in applying alternative methods of estimating each category of effect of changes in truck characteristics, leading to an assessment of the current state of understanding of the impact and needs for future research, data collection, and evaluation; and second, a critical synthesis of quantitative results of past prospective and retrospective estimates of each category of effect.

The results of these syntheses would inform the ability to reach firm conclusions about the consequences of changes in truck size and weight limits on safety, efficiency, infrastructure, and the environment.