ST. PAUL, Minn. — Bridges that connect Minnesota and Wisconsin across the Mississippi could withstand a direct collision from a barge, according to Minnesota’s chief bridge engineer. Ed Lutgen told the LaCrosse Tribune that piers are evaluated regularly to meet 1991 federal standards to withstand “a commercial vessel impact.” Lutgen was interviewed in the wake of the Baltimore disaster in March, when an ocean-going container ship brought down the Interstate 695 bridge over outer harbor. The had been designed in the 1970s. About bridges in general, Lutgen acknowledged “a lot of unknowns” when assessing the impact of a possible barge collision. But, he added, the Highway 43 in Winona and the Interstate 90 and bridges at Dresbach are up-to-standard, as are other border bridges: “Those designs account for site-specific conditions — including the geometry of the vessels, the speed, the weights, the river currents and the flood conditions– so it has been designed for those types of barges.”
Earlier: Periodic Minnesota bridge inspections due soon
State of bridges
Minnesota has 54 bridges that cross navigable waters as defined by the U.S. Coast Guard. The Army Corps of Engineers, which manages river traffic, has average of 2,200 commercial vessels annually pass through Lock and Dam 7 at Dresbach. A single barge can carry 1,500 tons of cargo. Bridge safety assessments and maintenance are the resosnbiityof state agencies. Examples:
> Iowa: Black Hawk Bridge at Lansing.
> Minnesota: Intestate 90 bridge at Dresbach, Highway43 bridge at Winona, and Clickner Bridge at Wabasha.
> Wisconsin Cass Strest Bridge in La LaCrosse.