The contractor that retrofitted the iconic Washington Avenue Bridge to accomodate light rail trains has won an award from the American Council of Engineering Companies of Minnesota.

AECOM, the international engineering and design firm selected by the Metropolitan Counci for the job, earned a 2013 Engineerint Excellence Grand Award for the $21 million makeover of the double decker bridge that spans the Mississippi River on the University of Minnesota.

The firm shared the award with the Met Council, according to a news release updating progress on the construction of the Central Corridor Light Rail Line. Known as the Green Line, trains will cross the bridge when the line between downtown Minneapolis and St. Paul opens in mid-2014.

Construction is 89 percent, according to a Met Council spokeswoman.

The retrofitted bridge includes two tracks in the center of the lower level of the bridge along with one traffic lane in each direction. The upper level is still open to pedestrians.

Preserving the existing 1,131-foot bridge, which was built in 1965, saved an estimated $80 to $100 from the Green Line's cost since a new bridge did not have to be built. It also kept construction on schedule since complete bridge replacement could have taken up to 2 years.

Photo credit: Metropolitan Council