Cost and Schedule Performance Analysis of Transportation Public-Private Partnership Projects

A public-private partnership (PPP) is a contractual agreement between public-sector and private-sector partners allowing more private-sector participation than is traditional. The literature on PPP in the transportation sector is vast and spans many different areas of research including construction finance, governance, and policymaking. However, research quantifying the project performance of PPP transportation infrastructure in the United States is lacking. This paper aims to quantify the cost and schedule performance associated with two major PPP delivery methods: design-build-finance (DBF) and design-build-finance-operate-maintain (DBFOM). The authors collected and verified data through professional data sets and structured interviews with key project constituents. The paper presents results from an analysis of 75 projects completed between 1995 and 2015, totaling approximately $39 billion in infrastructure development expenditures. Results show PPP projects in the data set exhibit an average cost change of 3.04% versus 9% for similar projects that used DB (which is already an aggressive baseline) and an average schedule change of 1.38%. These numbers represent significant improvements over traditional methods. Overall, this paper fills a crucial gap in the body of knowledge on PPP project performance by presenting a quantitative analysis of cost and schedule performance in the US transportation sector.