Severe congestion, delays caused by operation of the historic Stillwater Lift Bridge, and bridge condition and maintenance have prompted discussions and study of a new bridge over the St. Croix River for many years. Although a preferred alternative was selected as part of the 1995 Final Environmental Impact Statement (EIS), the alternative was not allowed to proceed because of its impact on the St. Croix River, which is part of the National Wild and Scenic River system. MnDOT and WisDOT initiated a new process, and SRF was retained to prepare Scoping and Scoping Decision Documents and the Supplemental EIS.
Extensive coordination and negotiation among federal, state, and local agencies was required to arrive at a workable solution and mitigate potential impacts. The Supplemental EIS was supported by a large number of specialized studies, including an origin-destination survey, extensive traffic forecasting, detailed traffic operations analysis, an economic impacts study, a visual impacts assessment and cultural resource studies. Groundbreaking work on cumulative impacts and innovative noise impact studies also addressed key issues for the project. Design played a key role in minimizing environmental impacts such as approach roadway impacts to the surrounding river bluffs, bridge design and aesthetic treatments appropriate to the Lower St. Croix River, and drainage and water resource engineering to protect area water quality.
The preferred design alternative that was developed by SRF and approved by MnDOT implemented numerous components to address specific stakeholders concerns, including speed, accessibility, pedestrian access, aesthetics, design standards, and the physical footprint of the proposed project. After years of study, the project has received funding and is moving forward into construction.