Construction Update
Preliminary site preparation, including dirt work and staging (arranging and organizing materials, equipment, and resources needed for the project), has begun. Construction on the embankment is anticipated to begin after the preparation work is complete. Because most of the early work will be off-site, minimal traffic disruption is anticipated.
More updates can be found on the Project Updates page.
Project Overview
The Montana Department of Transportation (MDT) is partnering with M.A. DeAtley Construction, Inc., to reconstruct sections of US Highway 191 (US 191) near the James Kipp Recreation Area and the Fred Robinson Bridge over the Missouri River. The US 191 – Mobridge Slide Repairs project will help stabilize a section of roadway that was damaged from landslides in the area.
The project area includes three different locations along US 191 which will be completed in two phases.
Phase 1
The first phase will include work at Site A (see map below), which is the largest area and impacts the section of road between mile markers 84 and 85. This slide has been an issue since the late 1950s but has worsened over the last decade.
Construction is anticipated to begin in spring 2025 and continue until fall of 2026.
Phase 1 improvements at Site A will include:
Beginning in 2025:
- Reconstruct embankments to mitigate landslide movements. This involves adding a toe berm and shear key the at the base of the former landslide (see visual below).
- Improve drainage
Beginning in 2026:
- Improve the grading of the roadway
- Construct a new roadway surface
- Upgrade safety features such as new guardrail, signage, and pavement markings
Single-lane closures and a 12-foot width restriction and will be in place when construction begins. Motorists can expect reduced speeds and possible delays when traveling through the project area. Up-to-date road conditions can be found on MDT 511.
Phase 2
Phase 2 of construction will involve work on additional landslide locations between mile markers 85 and 86 (Site B), north of the Mobridge Slide and near mile marker 89 (Site C), just north of the Missouri River. Phase 2 construction is anticipated to begin in 2027, depending on completion of design and availability of funding.
Phase 2 improvements (Site A and Site B):
- Final construction at Site A (jack-and-bore culvert and final pavement installation)
- Reconstruct the soil structures supporting the roadway to prevent further deterioration of the roadway
- Improve drainage features to reduce infiltration of surface water on the roadway
Phase 2 improvements (Site C):
- Widen the roadway
- Repair the roadway to address bumps and settlements caused by landslide (heaving)
Project Map
UPN 9919000