Interstate 29

I-29 Corridor Study

The Interstate 29 Corridor in the northwest reaches of the Sioux City metropolitan area serves the state of South Dakota and its local communities. We have the opportunity through an I-29 Corridor Study to establish a long-term plan that both modernizes the corridor while maintaining its versatility.

Study Background

The Interstate 29 (I-29) Corridor Study covers Union County, South Dakota, and includes portions of the interstate, interchanges, and cross streets within the urban boundary for the communities of North Sioux City and Dakota Dunes.

Over 11 miles of I-29 is due for major rehabilitation or reconstruction in the 2030 to 2035 timeframe. Past studies have identified the need for potential interchange improvements at exit 1 (Dakota Dunes Boulevard), exit 2 (River Drive), and exit 4 (Northshore Drive).

A potential exit 5 interchange was added to the I-29 Corridor Study in response to recent flooding events near exit 4 in North Sioux City. A possible location for the exit 5 interchange is being evaluated to enhance resiliency and provide an alternative route during future flooding events.

An implementation schedule is needed for I-29 construction projects throughout the corridor. An initial public meeting was held in 2023 to gather public feedback on the corridor vision and exits.

Interstate 29 Corridor Study Project Locations

Corridor Study map

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Interstate 29 Corridor Study Area

Corridor Study map

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Study Objectives

The need for this study was identified by the Study Advisory Team (SAT), which is comprised of state, regional, local, and federal agencies, based on a number of factors. The SAT and project team have established the following objectives for the study:

Determine a future vision for I-29 mainline infrastructure

Determine potential interchange concepts that meet study advisory team objectives

Create an implementation schedule for I-29 construction projects throughout the corridor

Prepare partner agencies for future environmental study, permitting, and design

Schedule

Project timeline.

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  • Project Kickoff - January 2023
  • Corridor Vision Complete - May 2023
  • Exit 1, Exit 2 and Exit 4 Stakeholder and Public Meeting #1 - July 2023
  • Corridor Needs Complete - November 2023
  • Solutions Identification Complete - January 2024
  • Design Concepts Complete (Exits 1 and 2) - May 2024
  • Flooding Event Near Exit 4 - June 2024
  • Regional Priorities Took Precedence over I-29 Study - Summer 2024
  • Coordination of Northshore Bypass/Exit 4 Next Steps - Fall 2024
  • Exit 5 Kickoff - January 2025
  • Exit 5 Concept Design - Ongoing 2025
  • Exit 5 Stakeholder and Public Meeting #1 (Public Feedback on Design) - September and October 2025
  • Public Meeting #2 (Feedback on I-29 Mainline and All Cross-Streets Exits) - February and March 2026
  • Study Recommendations on Design and Construction Sequences - April 2026
  • I-29 Corridor Study Completion - May 2026

Get Involved

Upcoming Events

A public meeting open house will be held from 4:30 - 6:30 p.m. on Thursday, Oct. 9, 2025, at the North Sioux Community Center, 205 Sodrac Dr., in North Sioux City, SD. The goal of this meeting is to share design options for the I-29 corridor, allow the public the opportunity to collaborate with the project team on the design options, and provide information about future corridor projects and development. This input will help the study team to document key community needs to address in design and to validate the timeline for future infrastructure projects associated with I-29.

The public meeting open house will include a prerecorded presentation and interactive activities, along with opportunities to visit with the project team and ask questions. The prerecorded presentation will be shown multiple times during the stakeholder meeting.

Written comments will be accepted on Thursday, Oct. 9, 2025, and through the study website until Thursday, Oct. 23, 2025.

October Meeting Materials

Past Events

A public meeting open house was held on Thursday, July 20, 2023, from 4:30 - 6:30 p.m. at City Hall in North Sioux City. This event provided an opportunity for the SDDOT and the SAT to introduce the I-29 Corridor Study and gather public input to help shape the vision of the corridor. The study team is gathering input on issues and needs to be addressed as a part of this study along the I-29 Corridor, which will help the study team shape the long-range vision for the corridor and create a plan to help guide future corridor projects and development.

July Meeting Materials