Background and Schedule
Thank you for visiting the project website for the "Interchange and Environmental Study for I-229 exits 3 and 4". These two studies, one for each exit, are analyzing alternatives developed in the previous I-229 Corridor Major Investment Study (MIS) and developing a preferred concept for each exit. Both studies will also include environmental review and documentation.
Project Updates
New! August 2024
The project will be hosting a public meeting open house on Wednesday, Sept. 4, 2024 from 5:30 p.m. to 7 p.m. at Lincoln High School to review the Environmental Assessment for the exit 4 (Cliff Avenue) interchange. Click here for more information.
Note: This public meeting open house is for exit 4 (Cliff Avenue) only, a separate open house will be held for exit 3 (Minnesota Avenue) at a future date.
June 2024 Update
The environmental review for the construction of a temporary bridge on I-229 over Cliff Avenue in preparation for the interchange reconstruction has been approved. Construction of the temporary bridge is planned for this summer (2024).
For more information about the project and schedule please visit the South Dakota Department of Transportation’s website at the following link.
https://dot.sd.gov/i229-cliff-ave-crossovers-pcn-07cy
Image below shows existing Cliff Avenue bridge. A temporary bridge will be constructed on the south side starting in Summer 2024 to accommodate traffic during construction of the interchange.
February 2024 Update
The project's environmental review process continues to advance with final adjustments to potential environmental impacts reflecting right-of-way modifications, floodplain requirements, and final design changes.
We are nearing the final steps in the environmental approval process for the construction of a temporary bridge on I-229 over Cliff Avenue in preparation for the I-229 / Exit 4 Interchange Project. If the environmental approvals occur this spring, the construction of the temporary bridge would start this summer (2024). More information will be provided on the temporary bridge construction as soon as it is available.
The I-229 / Exit 4 Interchange Project is also waiting for an environmental approval before it can be scheduled for construction. At this point we are anticipating a public meeting later this year and construction for this project is still tentatively planned for 2025-2026. More information will be provided for this project as soon as it is available.
Environmental Assessment (EA)
The EAs consider a wide variety of topics that address the human and natural environmental effects of the interchange projects. Project impacts can be either negative, neutral, or positive, depending on the resource. Sometimes impacts are labeled in terms of likeliness to affect (either adversely or not) the affected resource. The project must show compliance with all applicable federal, state, and local laws, Executive Orders, regulations, and ordinances and follow a prescriptive process, depending on the resource, to avoid, minimize, or mitigate unavoidable impacts to affected resources.
Examples of human environment resources that may be affected by the project include people and their residential areas and places of work, school, and play; roadway traffic and noise; park and recreation areas; views to and from the project area, and cultural resources such as archaeological sites and historic places. Examples of natural environmental resources that may be affected by the project include wetlands and other water resources (rivers, creeks, and streams), floodplains, threatened and endangered species of plants and animals, groundwater, and air quality.
The environmental documentation for the EA is being completed for both interchanges separately. This is required to allow for potential reevaluations of environmental topic areas if needed and allow for corrections so that both interchanges can proceed on coordinated construction schedules. The EA drafts are currently under review by SDDOT and FHWA.
Study Documents
Interchange Modification Justification Reports (IMJR)
Please check back periodically for additional project updates, or sign up for project updates and meeting notifications.
You may also visit the South Dakota Department of Transportation website at dot.sd.gov