New I-35W Minneapolis bridge opens

The new Interstate 35W St. Anthony Falls Bridge in Minneapolis, Minnesota, United States was opened shortly after 5 AM today. It replaces a bridge which collapsed last year, killing 13 people.

A fire engine and ambulance were first across on each side. In each direction, a line of State Highway Patrol cars was followed by a formation of Department of Transportation construction trucks. A cluster of awaiting vehicles went honking across for a few minutes, then traffic returned to the sparse levels more typical of the pre-dawn period.

The September 18 opening was well ahead of the scheduled December 24 goal, earning the contractor, Flatiron-Manson, up to $19.6 million in performance bonuses.

The bridge is 189 feet wide, with a main span length of 504 feet and a deck height of over 100 feet above the Mississippi River. Traffic is expected to return to previous levels of 141,000 vehicles per day on the 10 lanes. The accelerated construction (of only 11 months) was accomplished by pouring 120 concrete sections in heated pole barns, and then lifting them all into place via a crane mounted on a river barge. The bridge contains 323 electronic sensors for real-time monitoring of stresses and movement of the bridge components. It is illuminated with white light-emitting diodes.