A three-step process is being used to evaluate bridge crossing alternatives and select a preferred project alternative for the Osceola Bridge. This process begins with identifying a reasonable range of build concepts, including a no-build alternative. Each step will refine the alternatives through quantitative and qualitative environmental analysis. Each step looks at the remaining alternatives at a progressively greater level of detail. The outcome of the third step is the identification of a preferred alternative, which is the alternative that will proceed into final design and ultimately construction for the Hwy 243 Osceola Bridge project.
Bridge concepts will be evaluated using the criteria outlined in the Alternatives Evaluation Criteria document. Initial criteria include Bridge Condition and Structure Robustness. Additional criteria include bikeability/walkability, Social, Economic and Environmental considerations, and other factors like constructability and ability to reduce traffic impacts during construction.
Concepts being considered in step 1
A total of eight project concepts are under consideration in step 1 of the process. These alternatives are included on the map below. Descriptions follow.
No-Build Alternative: The No-Build Alternative (or “do nothing” alternative) includes routine bridge maintenance activities on the existing Hwy 243 Bridge. The existing bridge deck, superstructure, and piers would be left as-is.
Build Concept A: Concept A includes removal of the existing Hwy 243 bridge deck and superstructure and replacement with a new deck and superstructure. The existing bridge
piers would remain-in-place and be re-used with the rehabilitation concept.
Build Concept B: Concept B includes removing the existing Hwy 243 Bridge and constructing a new bridge and approach roadways along the existing alignment.
Build Concept C: Concept C includes constructing a new bridge parallel to the existing Hwy 243 bridge. The new bridge would be built to the north of the existing bridge. The existing Hwy 243 Bridge would be removed following construction of the new bridge.
Build Concept D: Concept D includes constructing a new bridge crossing parallel to the existing Hwy 243 bridge. The new bridge would be built to the south of the existing bridge. The existing Hwy 243 Bridge would be removed following construction of the new bridge.
Build Concept E: Concept E includes constructing a new bridge crossing north of the existing Hwy 243 bridge and realigning Hwy 23 on the Wisconsin Side to connect to the existing 2nd Avenue. The existing Hwy 243 Bridge and approach would be removed following construction of the new bridge.
Build Concept F: Concept F includes constructing a new bridge crossing along an entirely new Hwy 243 alignment between MN Hwy 95 and WI Hwy 35 outside of the Village of Osceola. The existing Hwy 243 Bridge would be removed following construction of the new bridge.
Build Concept G: Concept G includes constructing a tunnel under the St. Croix River along the existing Hwy 243 alignment from Minnesota to Wisconsin. The existing Hwy 243 Bridge would be removed following construction of the tunnel.
Below is a graphic illustrating the step 1 screening process. There were eight concepts screened in step 1. Four of these initial concepts were removed after the first screening for not meeting the project criteria. The step 2 analysis will look at these remaining 4 concepts and further develop them into alternatives. The 4 alternatives will then be screened based on the secondary criteria of bike and pedestrian considerations, as well as social, economic and environmental considerations.