Social Equity in Transportation Infrastructure Management: Quantitative Methods for Assessing and Improving the Distribution of Public Investments

 In this dissertation, I study the distributional equity of transportation infrastructure conditions in the United States. Grounding my interdisciplinary approach in infrastructure asset management practice and social justice theory, I develop several analytical methods for conducting quantitative equity screenings, determining the socioeconomic impacts of infrastructure quality, and rectifying inequities through improved project selection. Previous studies of community-level impacts have either focused on individual projects or the distribution of roadway condition across a single city. Thus, the distribution of infrastructure condition, maintenance actions during the operational life of the assets, and the associated impacts on the neighboring communities are under-studied. To complement these important studies and inform the stakeholder engagement processes that emanate from them, I scale quantitative social equity screenings to state and national infrastructure management programs. For nationwide studies of bridge and highway inventories, I find that the risks and burdens associated with roads and bridges in poor condition have asymmetrically been borne by socioeconomically disadvantaged and marginalized communities (Study 1, Chapter 2). Through econometric assessments of the communities near the highway, I find that the burdens from poor condition highways are associated with less employment, lower earnings, and less vehicle commuting (Study 2, Chapter 3). For bridges in the United States, I show that addressing these inequities with socially-aware project selecting criteria is feasible within realistic budgets and does not decrease the overall performance of the inventory (Study 3, Chapter 4). Beyond transportation infrastructure management in the United States, these methods could be adapted to assess equity and prioritize investment plans for a myriad of infrastructure systems and public services that have long life-cycles and entrenched footprints such as dams, tunnels, and other such assets.