Project Overview
The Montana Department of Transportation’s (MDT) Orange Street Tunnel project in Missoula will include rehabilitation and preservation work on the existing structure. Built in 1939, this tunnel is on an important route through Missoula and is heavily used by businesses, tourists, and the community.
The Orange Street Tunnel will be rehabilitated to extend its service life as follows:
- Replace the existing concrete superstructure that supports Railroad Street West and North 1st Street West.
- Repair concrete on the tunnel and retaining walls.
- Replace sections of existing retaining wall near tunnel entrances.
- Minor roadway work associated with tunnel repairs.
- Replace tunnel lighting.
- Repair or replace existing railing along the approach walls and in the tunnel.
During construction, single-lane traffic, detours, reduced speeds, temporary closures, and width restrictions are expected.
Project Schedule
The Orange Street Tunnel project is currently in the design phase. A construction start date has not yet been determined and is dependent upon finalization of the contract.
A more comprehensive schedule will be defined and shared as the project develops.
Project Location Map
Stay Involved, Stay Informed
Stakeholder and public feedback is encouraged throughout all project phases to help MDT develop solutions for design and construction that best meet traffic and safety needs of the area and all who use this route. To sign up for email updates, contact Brittany at
New project information will be posted on this website as it becomes available.
Comments can be submitted electronically. To submit a comment, visit MDT’s Online Comment Form.
Please note that your comments are for the Orange Street Tunnel, UPN 9941000.
UPN 9941000