The Montana Department of Transportation and Frontier West are rehabilitating the eastbound bridge that carries Interstate 90 (I 90) over the Clark Fork River, 5 miles east of Alberton.
The project will rehabilitate the bridge by replacing the bridge deck (driving surface), adding new barrier and guardrail, and improving drainage.
Planned improvements include:
- Full bridge deck (driving surface) replacement.
- New barrier and guardrail.
- Replacement of expansion joints.
- Improved drainage.
- Bridge approach roadway work.
- Minor substructure repair.
- Structure spot cleaning and painting.
- Transverse deck grooving.
What are expansion joints and transverse deck grooving?
Expansion joints: Bridge decks expand and contract several inches due to fluctuations in temperature. For the bridge deck not to buckle or push into the ends of the adjoining roadway surfaces, expansion joints are designed into the structure to allow for movement. When you cross over a set of steel plates on a bridge, that is usually the expansion joint.
Transverse deck grooving: After a new bridge deck is built, the surface of the concrete is smooth with limited skid resistance. To increase skid resistance for vehicle safety and shed water to the gutters, shallow crossway saw cuts are placed every few inches with a concrete saw blade down the entire bridge deck. These grooves add traction and help water from ponding on the deck.
Transverse Deck Grooving
Why is the project needed?
This bridge was originally constructed in 1979 and has gone through several minor rehabilitations. The bridge remains safe to drive on but needs major rehabilitation work. This project will make cost-effective improvements and repairs to the existing structure that will extend its service life for many years.
Stay Informed During Construction
Communication with the public is important to MDT and the success of the project. The community will be notified about public involvement opportunities, and construction and traffic activities, at key project milestones throughout the construction process. MDT will notify the public through the project website, local media, mailings, social media, and email and text notifications.
Current construction information and road conditions can be found on the MDT Travel Info App.