The new St. Croix River bridge, one of the largest construction projects in Minnesota, won't open in 2016 as promised because building it has become more complicated than expected, state transportation agencies in Minnesota and Wisconsin said Friday.
"This is a very complex engineering project," said Commissioner Charlie Zelle of the Minnesota Department of Transportation (MnDOT). "This is only the second major bridge of its type built in the United States and the methods of construction are taking longer than anticipated."
The four-lane bridge will link Hwy. 36 at Oak Park Heights with Hwy. 64 in St. Croix County, Wis., replacing the Stillwater Lift Bridge as an interstate connection. Its delayed opening almost certainly will increase labor costs and could hurt Stillwater's plan to build a pedestrian plaza in its historic downtown district.
Problems became apparent in recent weeks when contractors told MnDOT "they're just to the point now where there's no way to recover that schedule anymore," Michael Beer, the project manager, said Friday. "As the summer progressed, certain items haven't gone as quickly as we hoped."
The delay wasn't caused by one problem, Beer said, but stems from a combination of challenges related to the unusual style of the bridge. It relies on tensioned cables to hold segments together, and fusing the metal known as rebar is taking longer than expected, he said.
"It's such a dense network of interweaving rebar," he said. "It takes longer for the contractor's workers to assemble that than on a typical bridge. There are a lot of areas like that on this project, so those portions just haven't been able to be produced as quickly as what the contractor had originally anticipated."
The transportation agencies have said the new bridge and its approach highways could cost up to $676 million. That price tag also includes money for historic preservation and for environmental work to protect the St. Croix River.
"Disappointed — but given the scope of the project, it's understandable," Gary Kriesel, chairman of the Washington County Board, said of the delay. "You've got to do it right the first time."