Click

for a Web-exclusive, behind-the-scenes slideshow.

Editors Note: On Saturday morning April 26, 2008, 50 people from the Twin Cities area met the project managers from Mn/DOT and Flatiron/Manson to hear about reconstruction progress concerning the I-35W bridge. It was 30? F, snowing, and the wind was coming down the river channel at about 20 mph. As one aging resident put it, "We are Minnesotans. We're used to this" As many as 450 people show up for these weekly Saturday construction tours and as few as four. For the public and everyone involved in the construction, the rebuilding of the bridge is a very emotional issue.

On Aug. 1, 2007, news around the world carried the story of the collapse of the I-35W structural steel bridge crossing over the Mississippi River in Minneapolis, resulting in the deaths of 13 people and 145 injuries. It shocked the nation and caused awareness of the sad, deteriorating state of our nation's infrastructure. The rebuilding of the bridge became an immediate priority because the freeway is a vital cross-town link for the Twin City area causing expenses to citizens totaling more than $440,000 per day in additional user impacts. Shortly after the collapse, the Minnesota Department of Transportation (Mn/DOT) invited construction companies to submit "Best Value Design/Build" proposals for the reconstruction. Each of the four bidders, aligned with an engineering firm, presented their proposals. A panel of experts convened by Mn/DOT evaluated each proposal on the basis of price, time to construct, design, quality, safety, and the technical content of the proposal. On Oct. 8, Mn/DOT awarded the contract to the joint venture of Flatiron Constructors, Longmont, Colo., and Manson Construction, Seattle--with FIGG Engineering Group (FIGG), Tallahassee, doing the design work and being the engineer of record. Construction began on Oct. 15 and on Nov. 1, a test shaft was drilled. On Oct. 24, FIGG held a full day charrette to engage the public in the design process.

The winning proposal was the only one submitted for a structural concrete bridge. Flatiron's project manager, Peter Sanderson says they decided to use structural concrete because they would stand a better chance of completing the bridge on time and have better control of their very tight schedule.

The best value design/build construction approach

Terry Ward, Mn/DOT's deputy project manager, says there were three bid sections for this project: price, time, and "Best Value" In the Best Value section, the important areas included safety, quality, public relations (including public involvement in the design process), aesthetics, and enhancements. The concept of Best Value Design/Build is at the heart of the I-35W bridge project and Jon Chiglo, the project manager for Mn/DOT, says it's their seventh Best Value project. He likes this process for the following reasons:

• Safety becomes a high priority.
• There is a high emphasis on quality.
• The design approach is taken into account in the bid process.
• Design/build requires enhanced communication to be successful--more so than less aggressive projects.
• The contractor has more control over the schedule.
• Mn/DOT has the opportunity to evaluate the experience of the team and their approach as part of the selection process.
• To achieve success, an enhanced partnering process is required.

Chiglo says Mn/DOT gives away some of their control on Best Value Design/Build projects, giving considerable latitude and flexibility to the bidder. In the case of the I-35W bridge, they provided the contractor with geometric layout, environmental requirements, drainage requirements, a deadline for completion of Dec. 24, 2008, and invited innovation. They also defined six sub-standard roadway geometric design elements to the original I-35W freeway approaches to the bridge in the original "Request for Proposals," inviting (but not requiring) bidders to eliminate them as part of the project. Mn/DOT also requires public involvement in decisions concerning the design of their bridges so contractors must provide details in the bids about how the public will be involved.

For the contractor, deciding to bid a Best Value Design/Build project imposes additional responsibilities. Each bidder was required to provide their own design for the bridge, so they approached bridge design/engineering firms to work with them. Because they are responsible for the design, they aren't entitled to change orders based on quantities or design conflicts. Ward says the upfront costs of Best Value contracts are often a little higher but over the life of a contract there is minimal cost growth due to change orders and the final numbers turn out to be close to other forms of bidding. Also schedule benefits can be quite significant.

The four entities who submitted bids had one month to do research, complete designs, and present their proposals to the review panel, which received three proposals for structural steel bridges and one for structural concrete.