Montana Department of Transportation


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Active Project - Bonner Bridges Project

Bonner Bridges Project

Project Overview

Bonner Bridges Project image

The Montana Department of Transportation continues the reconstruction of the Interstate 90 bridges spanning the Blackfoot River at Bonner.

The two-year, $15 million project calls for replacing the 53-year-old bridges with upgraded structures.

The Montana Department of Transportation does not anticipate a significant impact to I-90 traffic during construction, scheduled from April through November 2019. Constructing is occurring in two phases, with the eastbound bridge reconstruction completed in 2018.

Starting April 2019, the westbound bridge will be replaced with two-way traffic routed on the new eastbound bridge.

During construction, traffic will be two-way over the eastbound bridge. The traveling public should be aware of decreased speeds over the eastbound bridge, spanning from just before the Bonner interchange to just past the second bridge deck. Construction on the Bonner Bridges will continue through the summer and fall months.

Blackfoot River access will be restricted in spring 2019 to protect floaters and other recreational users from construction-related hazards. Periodic river closures will take place during the remainder of construction season.

To accelerate completion of the I-90 bridges, MDT entered into a design-build contract with Helena-based engineering firm Morrison Maierle and Missoula-based construction firm Frontier West LLC.

Stay in the Know

For email updates about the project,

Hotline: Call 406-207-4484 during business hours.

Text Alerts: Text BONNER to 41411 for current river closure information during active construction*.

*Msg. and data rates apply. 1 msg/week. Reply STOP to opt-out at any time. Reply HELP for help. Text alerts are only active throughout the duration of Montana Department of Transportation work on Bonner Bridges; alerts will not be sent for closures in any other area of the Blackfoot River or any other waterway in Missoula. Visit our security policy for terms and privacy policy.