Anti-icing system eyed in bridge collapse

MINNEAPOLIS, Aug. 23 (UPI) -- Investigators say they are studying an automated bridge anti-icing system as part of their probe into why Minnesota’s Interstate 35W bridge collapsed.

The $618,000 system was installed in 1999 to help prevent accidents by keeping the bridge deck free of snow and ice.

The 35W was the first bridge of its size to get such a system, and officials said it worked and credited it with reducing accidents by 68 percent.

However, the National Transportation Safety Board is looking at whether it may have also contributed to corrosion on the bridge, which fell into the Mississippi River during afternoon rush hour on Aug. 1, leaving 13 dead, the St. Paul Pioneer Press reported Thursday.

Two weeks ago, the NTSB said it was studying the bridge’s gusset plates, which are used to join the steel girders of the truss bridge.

NTSB Chairman Mark Rosenker said in Minneapolis Wednesday his agency is still interested in the gusset plates, but he warned several other potential causes are still being studied.