Public-Private Partnerships (PPP) are in the forefront of approaches to funding transportation infrastructure improvements. Highlighted in the highway area by long-term leases of the Chicago Skyway and Indiana Toll Road, a variety of states are investigating the use of public private partnerships either as “Brownfield” leases like the Chicago and Indiana cases, or “Greenfield” Design, Build, Operate, Transfer arrangements. These and other PPP projects raise a variety of issues, including the length of the lease, toll escalation permitted, and use of funds. This paper develops a rationale for PPPs in transportation, evaluates several approaches to PPPs using this rationale, and analyzes some of the difficult issues that can surface.
