PROJECT DELIVERY APPROACH: A KEY FACTOR IN UNCERTAINTY

Up to recent decades a certain method was known for civil projects delivery, called D.B.B (Design- Bid-Build), that comprised of three parties: client (owner of the project and employer of other parties), engineer (responsible of design and technical affairs) and contractor (constructor of the project according to engineer’s expertise). In Iran Design-Build has gained a considerable attention in recent years as an implementation method for major civil projects. Design-Build offers some certain advantages to owners and in appropriate conditions can be expected to be a desirable method of implementing such projects in the future. This paper shows some of the uncertainties that must be addressed by owners and engineers working on behalf of owners, and in particular to address dam projects. In studies done on dam projects especially on disputes, we have explored the uncertainty regarding the project, categorizing in four items as below: 􀂃 Design (the sections performed by the contractor) 􀂃 Completion on scheduled time 􀂃 Cost variation 􀂃 Safety of the work Observation on projects of the same nature, but delivered differently, reveal that special consideration should be paid when selecting D-B as the project delivery system. Many drawbacks could occur if preliminary investigations have not been done properly.