Realized economic efficiency of road project delivery systems

Lately project delivery methods where the implementer offers broader service packages are increasingly used in infrastructure projects worldwide. At the same time, the number of alternative project delivery methods has increased making selection of the best one difficult. The road authority must understand the features of the methods in order to select the most effective ones in terms of economic efficiency. To assist in the selection, this research compared the operating principles and performance of design-bid-build, construction management, design-build (DB), and design-build-maintain (DBM) based on an international interview survey and an extensive literature review. Opinions presented by the interviewees and literature review all pointed to the same direction. Based on the analysis of road procurement, broader service packages give, on average, better value for the money and enable clients to attain their goals better than more traditional methods. DB and DBM seem to outperform more conservative procurement methods both in cost and value generation terms. Each method, however, is particularly suitable for specific projects and should be selected accordingly.