Nearly a month after the collapse of the I-35W bridge into the Mississippi River in Minneapolis, MN, the final victim has been recovered from the water and removal has begun to move faster. The NTSB (National Transportation Safety Board) is still on the scene and expects to remain there “at least until November,” says Terry Williams, media contact.
On site, the NTSB will sometimes ask contractors removing the debris to take it to a separate site for further investigation, according to Kevin Gutknecht, program team leader for the Minnesota Department of Transportation (MnDOT). Otherwise the process is moving along fairly quickly.
The NTSB is continuing to look into all potential factors that could have caused the bridge collapse, including the de-icing system installed on the bridge in 1997 and the potentially corrosive properties of the chemicals it uses, as well as the weight of the construction equipment on the bridge prior to the collapse. According to a release from the NTSB, “the combined weight of the loads and construction vehicles is about 575,000 pounds.”
MnDOT is now focusing on clearing the river for barge traffic. “The navigation channel isn’t quite clear, so that’s certainly a priority,” says Gutknecht.
Materials recovered during the removal process will be recycled. “Concrete will be taken someplace and pulverized into class 5 fill and the metal will all be taken by scrap dealers and recycled,” says Gutknecht.
With removal moving at a faster pace, Gutknecht expects the construction of the new bridge to begin in the middle of October. Contractor proposals from the four remaining companies applying for the project are due by mid-September. The new bridge is expected to span the river where the original bridge once stood.