Construction Complete on Dalton Mountain Road Bridge Replacement Project

LINCOLN, Mont: The Montana Department of Transportation and Sletten Construction, in collaboration with Lewis and Clark County, are pleased to announce that the new Dalton Mountain Road Bridge is now open following a successful inspection on Friday morning.

The new bridge replaces a timber structure that stood in the same location for 68 years. In 2017, the old bridge suffered several foundation pile failures, and Lewis and Clark County nominated it for replacement. Emergency repairs were made in the fall of 2017, temporarily stabilizing the bridge so it could reopen to the public as a one-lane bridge with an 8-ton weight limit.

This project, which was funded through MDT's Off-System Bridge Program and the Montana Coal Endowment Program, replaced the aging timber structure to improve accessibility and enhance motorist safety along Dalton Mountain Road. The new structure is a single-span steel pony truss with a cast-in-place concrete deck. The single-span design was chosen because it has no in-stream piers, which reduced in-river construction time and lowers the risk of future debris snags.

"We want to thank the community of Lincoln for their patience and support during the construction of the new Dalton Mountain Road Bridge," said MDT Great Falls District Administrator Jim Wingerter. "We understand that the detour was not easy for residents living south of the bridge, but we are pleased to deliver the new structure ahead of schedule. We look forward to this bridge serving the Lincoln community and Blackfoot River recreators for many years to come."

The new bridge spans 150 feet and features two 12-foot travel lanes with 1-foot shoulders. To enhance safety and maximize sight distances, the new bridge has a slightly different alignment than the old one. Another safety enhancement is the addition of bridge railings. Ditch and irrigation work were also completed to improve drainage as part of this project.

For more information, visit the project webpage: https://mdt.mt.gov/pubinvolve/daltonbridge/

If you have any questions, comments, or feedback on this project or the public involvement process, please get in touch with Melissa Shannon at [email protected] or 406-422-2922.