Multnomah County in the US state of Oregon has decided against using competitive low-price bidding for construction of the US$330 million Sellwood Bridge replacement. The county's commissioners have instead chosen the construction manager/general contractor (CM/CG) method, seeing it as having a number of advantages including facilitating value engineering and bringing cost savings.
The approach will involve appointing a CM/GC contractor during the design phase to provide construction expertise. Near the completion of design, the CM/GC contractor will negotiate a guaranteed maximum price and will be responsible for carrying out some of the work while subcontracting out the remainder.
A report presented to yesterday's meeting said that CM/CG would bring a range of benefits. Its use is expected to result in substantial cost savings, bridge services manager Ian Cannon told the meeting.
The project's record of decision is expected this summer, enabling the county to move forward with design, acquisition of rights of way and ultimately construction. The bridge type was narrowed down to a box girder, delta frame or deck arch design last year. "Due to the complex nature of the project, the desire to move forward expeditiously and the desire to minimise project risks, the county began investigating alternative contracting methods," said Cannon. One of the benefits identified in the investigation was CM/CG's flexibility for adapting to change.
CM/CG is becoming more common in Oregon and was given impetus by a report published in 2002 by the Oregon Public Contracting Coalition.
