![Dalton Mountain Road Bridge Replacement Project logo](images/logo.png)
August 29, 2024
In cooperation with Lewis and Clark County, the Montana Department of Transportation (MDT) and Sletten Construction are replacing the Dalton Mountain Road Bridge over the Blackfoot River, 3 miles west of Lincoln. A detour is in place via Herrin Lake Road, Stemple Pass Road, and Montana Highway 200 (MT 200). See map below.
This week, crews are pouring the cap on the south side of the river and the backwall on the north side of the river. Bridge caps sit on top of the drilled shafts and will support the truss on each side of the river. Backwalls sit above the cap and support the approach slab where the road ties into the bridge deck.
LABOR DAY: Crews will pause construction activities for the Labor Day weekend by 3 p.m. on Friday, August 30, and resume on Tuesday, September 3.
Next week, crews will pour the backwall on the south side of the river, and the first two loads of steel structures for the trusses will arrive and be installed. Crews will also place additional rip rap (large rocks that form the structure of the riverbank) and work on riverbank protection, including planting willows. This work will stabilize the riverbank to prevent erosion, reduce sediment, and protect the bridge's infrastructure.
August 23, 2024
The Montana Department of Transportation (MDT) and Sletten Construction, in cooperation with Lewis and Clark County, are replacing the Dalton Mountain Road Bridge over the Blackfoot River, 3 miles west of Lincoln. A detour is in place via Herrin Lake Road, Stemple Pass Road, and Montana Highway 200 (MT 200).
This week, crews removed the concrete form for the cap on the south side of the river. Bridge caps sit on top of the drilled shafts and will support the truss on each side of the river. Forms are removed after the concrete hardens so work can continue on the cap.
Next week, crews will be placing additional rip rap (large rocks that form the structure of the riverbank) and working on riverbank protection, including planting willows. This work will stabilize the riverbank to prevent erosion, reduce sediment, and protect the infrastructure of the bridge.
August 15, 2024
The Montana Department of Transportation (MDT) and Sletten Construction, in cooperation with Lewis and Clark County, are replacing the Dalton Mountain Road Bridge over the Blackfoot River, 3 miles west of Lincoln. A detour is in place via Herrin Lake Road, Stemple Pass Road, and Montana Highway 200 (MT 200). See map below.
Work continues this week on the Dalton Mountain Road Bridge replacement project.
Sletten Construction is continuing work pouring concrete for the last drilled shaft on the south side of the river, as well as the cap on the north side of the river. Bridge caps sit on top of the drilled shafts and will support the truss on each side of the river.
Next week, crews will be preparing to form the concrete cap on the south side of the river. This work includes final testing of the drilled shafts, grading the area around the cap location, placing the rebar, and setting the concrete forms. Concrete placement for the south cap is scheduled for the week of August 26-30.
The rebar cage and forms for the concrete cap on the north side of the river.
Placing the concrete for the final drilled shaft on the south side of the river.
August 9, 2024
This week, Montana Department of Transportation engineers began testing the drilled shafts on the north side of the river for spaces or gaps in the concrete. It is important that the concrete is solid throughout the drilled shaft so that settling does not occur.
Sletten also continued work this week on the drilled shafts on the south side of the river, which will continue next week. Crews will also continue pouring the concrete caps that sit on top of the drilled shafts, which will support the new truss on each side of the river.
August 1, 2024
This week, Sletten Construction continues work on the drilled shafts, the first components of the bridge foundation. Crews will place a permanent shaft casing on the south side of the river at the end of this week. Drilling and concrete work on other shafts will resume next week.
Next week, Sletten will also begin preparing a concrete cap to be placed on the north side of the river. The concrete bridge caps sit on top of the drilled shafts and will support the truss on each side of the river.
July 25, 2024
This week, Sletten Construction began work on the drilled shafts, which are the first components of the bridge foundation. The crews drilled cylindrical shafts into the ground approximately 85’ deep and filled them with concrete. Sletten drilled the first shaft on Monday and placed concrete on Thursday.
Next week, crews will continue work on the drilled shafts and the bridge bents, which provide vertical support for the bridge. The new Dalton Mountain Road bridge will have four drilled shafts, two on each end of the bridge. Concrete caps and backwalls will then be placed on the shafts to complete the foundations for the bridge.
In addition to the drilled shaft work, crews will continue building the work structure for the crane and equipment to utilize during construction. Half of that structure is currently built, which is where the crane is sitting right now. The other half will be constructed on the south side so they can begin work on the south end foundation.
July 18, 2024
Work to replace the Dalton Mountain Road Bridge is continuing. Sletten, the construction contractor, has removed the old bridge. Lewis and Clark County has graded the detour route, and Sletten applied magnesium chloride to control dust.
Earlier this week, crews began building the contractor’s work structure for the cranes and other equipment to utilize during construction. The first step, driving piles that will support the structure, is in progress and will continue into next week. Nearby residents should expect noise during pile-driving operations. Workers will also be installing stone riprap on the south bank of the river this week. The riprap is designed to protect the new structure and stabilize the riverbank.
Next week, weather and other factors permitting, crews will begin work on the drilled shafts for the bridge. This entails drilling cylindrical shafts into the ground and filling them with concrete. Drilled shafts provide a strong foundation for the new bridge. Nearby residents should expect some minor noise associated with this work. Crews will also continue placing riprap on the south side of the river and building the work structure.
July 10, 2024
Work to replace the Dalton Mountain Road Bridge has begun and Sletten, the construction contractor, has already removed most of the old bridge. Lewis and Clark County has graded the detour route and Sletten applied magnesium chloride to the detour route to control dust.
Tomorrow morning (Thursday, July 11), workers will be moving a crane that has been assembled in the Montana Department of Transportation (MDT) maintenance yard north of Montana Highway 200 (MT 200) at Dalton Mountain Road. The traveling public should expect a minor delay as the workers move the crane across the roadway.
Next week, the crews will begin work on the drilled shafts for the bridge. This entails drilling or excavating cylindrical shafts into the ground and then filling them with concrete. Drilled shafts provide a strong foundation for the new bridge.
July 8, 2024
Starting on July 8, the Montana Department of Transportation (MDT) and Sletten Construction, in cooperation with Lewis and Clark County, will close the Dalton Mountain Road Bridge for demolition and reconstruction.
During the closure, traffic will be detoured around the project site on Herrin Lake Road and Stemple Pass Road. The detour length is approximately 11 miles, bridge end to bridge end.
When traveling during construction season, watch for the “cone zone” and workers on the highway. These workers spend their days working a short distance from fast-moving vehicles, and while they make every effort to work safely, they count on you to pay attention, slow down, and be careful as you pass through a work zone.