EXAMINING CHANGES TO TRAVEL PATTERNS OF NORTH CAROLINA TRAVELERS AFTER ROADWAY EXPANSIONS USING A SYNTHETIC CONTROL METHOD

Roadway expansions are associated with changes to traffic volumes on the affected road segment, but the effects of expansions on visitation to nearby destinations has not been described. Using data on twelve roadway expansion projects completed between 2018 and 2022 in the state of North Carolina and large-scale cell phone mobility data, this study describes the relationship between expansion projects and home-to-destination distances of travelers. Using a synthetic control method, I identify evidence of modest increases (3.6% to 5.9%) in average distances between visitors’ homes and visited locations, as compared to a synthetic control, after certain roadway expansions. However, there is no statistically significant change in the majority of the twelve cases, a result that may have been impacted by COVID-19-related changes to travel behavior. This study demonstrates a new method for studying the effect of road construction projects, integrating mobility data and route modeling over a large geographical area.