September opening eyed for Minnesota bridge replacement

6/19/2008

MINNEAPOLIS - Two halves of a sparkling new I-35W freeway bridge stretch toward each other over the Mississippi River, separated by a gap of about 200 feet that shrinks with each day as workers toil around the clock.

The old bridge collapsed Aug. 1, killing 13 people and severing a critical link in the state's largest city. But for the companies replacing it, the goal is more than just restoring traffic flow - finishing ahead of schedule could mean up to $27 million in extra payouts.

That carrot has the new bridge on track to open as early as September, three months before it must be finished under the builders' contract with the state.

"Things are getting done in days and weeks that normally take months and years," said Kevin Gutknecht, spokesman for the Minnesota Department of Transportation. "But the bottom line is there's 141,000 cars a day that have to go someplace else right now, and that's hard on everyone."

Project planners considered an alternate approach known as accelerated bridge construction, but that carries much higher costs.

Bill Halsband, vice president at Mammoet USA, a Texas accelerated construction firm that unsuccessfully bid for subcontracting work on the Minneapolis bridge, said he's not aware of any previous bridge of this size that has gone up so fast using conventional construction methods.

"Anything can be done if people put their minds and their wallets to it," Mr. Halsband said.

The main contractors, the team of Flatiron Constructors of Longmont, Colo., and Manson Construction of Seattle, submitted a bid of $234 million with a timetable of 437 days. The bid was the most expensive and lengthiest of the four submitted, but scored higher than the others on factors such as quality and aesthetics.

The builders could earn even more, depending on how soon the project is finished.

If the bridge is ready for vehicles to drive across it by Sept. 15, the contractors earn the full $27 million bonus - a goal Flatiron/Manson assistant project manager Bob Edwards said is achievable. Project managers said they should be able to set a firm opening date by the end of July.

Mr. Gutknecht said there's no reason to think the rapid pace will compromise safety. He said several layers of quality control include outside inspection of the plans, and of each stage of the work before it happens. The Minnesota Deparment of Transportation also has a team of inspectors on site, constantly reviewing every facet of the job.

Construction crews work around the clock, in 12-hour shifts. They worked through the coldest days of last winter, and stop only for lightning or extremely high winds. At the height of activity a few weeks ago, there were 600 construction workers at the site; the number has dropped to about 450.

The concrete segments of the bridge are being cast on site. The pieces are carried on a flatbed truck to a staging area a few hundred yards down the river, then loaded onto a barge and ferried up to the new bridge. A massive crane nicknamed "Big Ben," which sits atop another barge, lifts them into place.