A recent joint study by Arizona State University (ASU) and Arup represents a first effort to compare the cost- and schedule-overrun results of 12 significant highway P3 projects that have been completed in North America.  The selected projects had construction costs greater than ~US$90 million.  These 12 projects were analyzed and the results were compared with previous research studies by other researchers reporting on similar type and size Design-Bid-Build (DBB) or Design-Build (DB) highway projects.

The research results indicate the cost overruns in the sample of 12 P3 projects averaged 0.81% and schedule overruns averaged -0.30%, compared with 1.49% cost overruns and 11.04% schedule overruns for DB projects and 12.71% cost overruns and 4.34% schedule overruns for publicly financed large-scale DBB highway projects.