Quantifying Sustainable Pavements in Virginia—FHWA Climate Challenge Study

About the report

This study supports Virginia’s efforts to participate in the Federal Highway Administration’s Climate Challenge Program. The research team developed and applied OpenLCA models to evaluate the effects of key pavement treatments, including asphalt overlays, balanced mix designs, cold in-place recycling, full-depth reclamation, and Portland cement concrete paving. The research incorporated detailed data from more than 25 projects across Virginia and selected out-of-state case studies, collected through site visits, contractor records, and direct equipment monitoring. All modeled systems included emissions related to life cycle assessment modules A1, material extraction and production; A2, transport to production plant; A3, mixture production; A4, transport to construction site; and A5, construction, with results normalized to kg CO₂-equivalent per lane-mile and presented as global warming potential (GWP). Because data for asphalt-based mixtures were more readily available, the work focused on these materials.

The study evaluated more than 200 Environmental Product Declarations for asphalt mixtures based on data submitted by Virginia asphalt producers. Environmental Product Declarations were analyzed for A1 through A3 emissions and benchmarked against U.S. General Services Administration (GSA) national thresholds. When averaged by four mixture characteristics, most mixture GWP averages were lower than GSA’s national averages, with only one subset that did not meet the GSA’s “Best 20%” GWP criteria. Higher total material extraction and transport emissions (A1 and A2, respectively) were evident in specialty mixtures (e.g., polymer-modified mixtures and stone matrix asphalt). Emissions from material extraction and production (A1 and A3, respectively) typically dominated GWP values for asphalt projects studied. For both cold in-place recycling and full-depth reclamation projects, materials emissions (A1) accounted for most of A1 through A5 emissions—approximately 75% for cold in-place recycling and 97% for full-depth reclamation—primarily due to the high embodied carbon associated with cement production.

As part of the study, the research team also delivered life cycle assessment training to Virginia Department of Transportation staff and produced a roadmap for integrating life cycle assessment and Environmental Product Declaration data into project planning, procurement, and asset management. The roadmap aligns with trends for regional and national climate targets and decarbonization strategies for low-carbon transportation materials. The study recommends that the Virginia Transportation Research Council host a concluding workshop to provide additional training resources and knowledge transfer to Virginia Department of Transportation staff.

 

_{Disclaimer Statement:The contents of this report reflect the views of the author(s), who is responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the Virginia Department of Transportation, the Commonwealth Transportation Board, or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation. Any inclusion of manufacturer names, trade names, or trademarks is for identification purposes only and is not to be considered an endorsement.}

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