Socioeconomic impacts of transportation public-private partnerships: A dynamic CGE assessment

- A new P3 evaluation framework was established to measure socioeconomic impacts of transportation projects.
- A dynamic computable general equilibrium model is developed for the assessment.
- The model measures infrastructure capital expenditure and tax shock effects.
- The modeling framework provides more accurate P3 outcome assessments.

While value-for-money and benefit-cost analyses represent traditional approaches for public-private partnership (P3) evaluation, these methods primarily focus on direct, project-level impacts. Indirect regional economic and/or social welfare impacts are generally ignored. This study fills the gap by investigating transportation infrastructure P3's socioeconomic impacts using a dynamic computable general equilibrium (CGE) model. Using the U.S. Commonwealth of Virginia's I-495 Express Lanes project as an example, the model measures infrastructure capital expenditure and tax shock effects and compares them with two public sector comparators (PSCs) representing lower- and upper-bound scenarios. The model also captures the impacts of capital accumulation and temporal variations during the 2008-2012 construction period. The simulation results show that by alleviating the regional economy's collected tax burden, P3s generate greater positive gross economic output and welfare impacts than traditional public financing models.