The I 15 Bridge Rehabilitation - Jefferson City and Clancy Area projects will repair and rehabilitate 12 bridges in southwestern Montana along I 15 between Helena and Jefferson City. The bridges are aging and in need of repairs and routine upkeep. They are safe to drive on, but it is essential to implement needed repairs to keep them safe and functional.
The Montana Department of Transportation (MDT) proactively invests in and improves Montana’s aging infrastructure. This investment maintains Montana’s vital connections and protects the traveling public.
|MDT Structure ID||Feature Intersected||Location||County|
|03221||Jefferson County Route 926 Bridge over I 15||1 mi N of Montana City||JEFFERSON|
|01175||I 15 Bridge over Abandoned Railroad NB||0.6 mi S of Montana City||JEFFERSON|
|01176||I 15 Bridge over Abandoned Railroad SB||0.6 mi S of Montana City||JEFFERSON|
|01173||I 15 Bridge over Frontage Road SB||1.9 mi S of Montana City||JEFFERSON|
|01172||I 15 Bridge over Frontage Road NB||1.9 mi S of Montana City||JEFFERSON|
|01171||I 15 Bridge over Lump Gulch Rd SB||0.6 mi N of Clancy||JEFFERSON|
|01170||I 15 Bridge over Lump Gulch Rd NB||0.6 mi N of Clancy||JEFFERSON|
|01168||Clancy Interchange NB||Clancy||JEFFERSON|
|01169||Clancy Interchange SB||Clancy||JEFFERSON|
|01167||Prickly Pear Creek||0.6 mi S of Clancy||JEFFERSON|
|01166||Prickly Pear Creek||1.2 mi S of Clancy||JEFFERSON|
|03220||Jefferson City Interchange||Jefferson City||JEFFERSON|
Why is this project important?
The I 15 Bridge Rehabilitation - Jefferson City and Clancy Area project aims to keep Montana’s bridges safe, resilient, economical, and reliable. The MDT Bridge Bureau is responsible for over 5,000 bridges in the state, and they inspect, evaluate, replace, rehabilitate, and preserve structures under their jurisdiction.
This design phase project aims to assess the options for rehabilitating all 12 bridges to increase their service life. MDT and partner project engineers with TD&H consider dozens of data points to find a unique solution for the preservation and enhancement of each bridge.
What does this mean to me?
The design phase is the public’s opportunity to provide MDT with information and feedback regarding how local communities use these bridges and nearby roadways. There will be further opportunities to provide input as MDT develops the plans for each bridge.
2021-2022 Bridge Design Phase
- Determine rehabilitation needs, such as crack sealing bridge decks, repairing deck joints, repairing spalling concrete, and rail revisions to enhance safety
- Develop design plans
Engineer to English
- Bridge Deck – the flat, drivable surface of a bridge supported by beams, trusses, girders, columns, etc.
- Crack Seal – when products are applied to the road or bridge deck to fill cracks and prevent them from getting water, sand, plants, rocks, etc. in them
- Deck Joints – places where pieces of the bridge come together; they allow the road to expand and contract during temperature changes without breaking or cracking
- Rail Revision – modifying the metal or concrete guard rails along the bridge
- Spalling – when small chunks of concrete break or flake off due to weather or damage
MDT has undertaken an ambitious goal through Vision Zero to eliminate deaths and serious injuries on Montana’s highways. MDT is working towards Vision Zero to ensure Montana’s thousands of miles of state roads and highways are built and maintained with safety as the first concern. MDT is committed to providing transportation systems and safe and affordable services, protecting the environment, and supporting economic growth for Montana.
Public involvement is vital to MDT and the success of the project. As the project progresses, the community will be notified about public involvement opportunities via this website, local media, postcards, social media channels, and other means.
MDT encourages questions and comments about the project. You can submit them through the MDT Comment page or directly to our team at
UPN 9782000 & 9783000