ST. PAUL – The Minnesota and Wisconsin departments of transportation have selected the architectural and engineering firm HDR of Omaha, Neb., along with its partner, Buckland & Taylor of Seattle, to lead the design effort for the St. Croix Crossing Bridge, officials announced Tuesday.
The 3,460-foot long bridge will span the St. Croix River between Oak Park Heights and St. Joseph Township, Wis., and replace the Lift Bridge as primary St. Croix River crossing point locally.
Although headquartered in Omaha, HDR has a Minneapolis office. The company is designing the Cayuga project that will reconstruct Interstate 35 from University to Maryland avenues, including replacement of the Cayuga Bridge, Pennsylvania Avenue Bridge and railroad bridges along I-35E
The $14.2 million contract will develop the extradosed-type bridge design that was selected by a community stakeholder group. That design is a hybrid of a concrete box girder structure and a cable-stayed structure and is lower in height than a typical cable-stayed bridge.
The bridge design minimizes environmental impacts by keeping tower heights below the river bluffs and reducing the number of piers in the river. When completed, the St. Croix Crossing will be the second extradosed bridge in the United States; the first extradosed bridge – the Pearl Harbor Memorial Bridge on Interstate 95 – is currently being constructed in Connecticut.
The four-lane St. Croix Crossing Bridge, estimated to cost between $280 and $310 million, will be constructed using the design-bid-build method. The bridge is a part of the larger St. Croix Crossing project, which includes expressway approaches on either side of the bridge in Minnesota and Wisconsin.
The project also includes an extensive trail facility for pedestrians and bicyclists, as well as historic and environmental mitigation efforts. The total cost for the entire St. Croix Crossing project is estimated between $580 and $676 million.
The design work by HDR and Buckland & Taylor will take approximately one year to complete with construction of the bridge anticipated to start in fall 2013.