The South Dakota Department of Transportation (SDDOT) study of the Platte-Winner Bridge has proceeded through environmental studies this spring. Among SDDOT’s major bridges, the Highway 44 Platte-Winner bridge has been determined to be a top priority for replacement, with construction of a new bridge currently scheduled for the mid-2020s timeframe. Ongoing studies of the bridge and coordination with project partners are focused on identification of a preferred alternative for a new bridge type and location. At public meetings held in May and December of 2017, SDDOT reinforced its commitment to maintaining traffic on this regionally-important bridge during construction. This commitment means that the new bridge will need to be in a new location so the existing bridge can remain open during construction of the replacement structure.
To understand the wide range of potential impacts of the proposed project and document the decision-making process for a new bridge, SDDOT is preparing an Environmental Assessment (EA). Studies conducted to date have helped confirm the existing Highway 44 corridor between Highway 47 and Highway 50 has sufficient capacity to meet long-term traffic needs. Additionally, geologic conditions in this corridor have historically created maintenance challenges for SDDOT, as erosion and landslides pose risks to the stability of Highway 44. Because of these conditions and the desire to minimize environmental impacts of the proposed project, SDDOT has narrowed its range of new bridge locations to within several hundred feet of the existing bridge.
Continued coordination with other agencies, stakeholders, and the general public is required to complete the EA. The area being considered for a new bridge location will require use of lands within the Snake Creek Recreation Area, a state park managed by the South Dakota Department of Game, Fish, and Parks (SDGFP). As a result, SDDOT is working with SDGFP to understand what impacts to the park may occur and how those impacts can be mitigated. SDDOT is also working with the U.S. Army Corps of Engineers to evaluate the potential impact to cultural or historic resources that may be found in the vicinity of the new bridge. Part of that effort included an archeological survey this May. Sites near the potential new bridge and its associated roadway were studied. SDDOT’s commitment to environmental stewardship includes outreach to tribes. In this case, representatives from the Yankton Sioux Tribe were present with the SDDOT-hired team of archeologists during the investigation for historic resources.
Results from these ongoing agency coordination efforts will be instrumental in the determination of a preferred alternative for this project. When SDDOT makes the decision (expected later this year), the EA will be published and shared online and at public meetings for comment. Previous meeting information and studies of the Platte-Winner Bridge can be found on the project website, www.sd44bridge.com.