Project Overview
The Lewistown area is actively planning for a period of growth that will result in increased traffic throughout the region. As part of the preparations for this expansion, the Montana Department of Transportation (MDT) will replace 11 aging bridges through the Lewistown Area Bridges-DAR Structures Project.
This project is a collaboration with the Department of Defense (DOD) and is partially funded through the Defense Access Road (DAR) program, which supports essential highway improvements for defense initiatives.
Eight bridges are located on Montana Highway 81 (MT 81) between the intersections with Montana Highway 80 (MT 80), west of Denton, and US Highway 191 (US 191), north of Lewistown. The other three structures are located on Montana Secondary Highway 400 (S 400) southwest of Hobson, Montana Secondary Highway 238 (S 238) southeast of Lewistown, and Montana Secondary Highway 297 (S 297) north of Shawmut.
Montana-based contractor Sletten Construction and engineering design consultant Morrison-Maierle have been awarded the project and have begun the initial design phase.
Project Approach
To replace the bridges as quickly as possible, the project is utilizing a Progressive Design-Build contracting method. This innovative hybrid approach enables multiple bridges to be bundled under one contract, allowing Morrison-Maierle to work alongside Sletten Construction from the beginning of the project. This partnership streamlines the process, efficiently moving bridge replacements from the design phase to construction. As a result, the project team can develop better solutions, reduce project costs, ensure efficient environmental approvals, and maintain quality, all while expediting project delivery.
Project Timeline
Fall 2024 – Surveying and Environmental Fieldwork
Winter 2024 to Spring 2026 – Project Design Phase
Spring 2025 – Project Open House
Spring 2026 to Summer 2028 – Construction
The project timeline is dependent on completion of design and availability of funding.
Bridge Replacement Locations and Schedule
The bridges to be replaced are divided into two construction packages. The first package will be replaced in 2026 – 2027 and the second in 2027 – 2028.
The order of bridges to be replaced and the tentative construction schedule are subject to change due to funding availability, weather, and unforeseen factors.
| Tentative Construction Schedule | MDT Structure ID | Structure to be Replaced | Location | Route | Mile Marker (MM) | County |
|---|---|---|---|---|---|---|
| 2026-2027 | 06209 | Dry Wolf Creek Bridge | 6 miles southeast of Denton | MT 81 | 19.9 | Fergus |
| 2026-2027 | 06216 | Drainage Bridge | 6 miles west of Brooks | MT 81 | 34.9 | Fergus |
| 2026-2027 | 06217 | Drainage Bridge | 5 miles west of Brooks | MT 81 | 35.4 | Fergus |
| 2026-2027 | 06219 | Drainage Bridge | 4 miles west of Brooks | MT 81 | 36.6 | Fergus |
| 2026-2027 | 06606 | Deadman’s Basin Canal Bridge | 1 mile north of Shawmut | S 297 | 0.9 | Wheatland |
| 2027-2028 | 06206 | Coffee Creek Bridge | Coffee Creek | MT 81 | 6.1 | Fergus |
| 2027-2028 | 06207 | Coffee Creek Tributary Bridge | 0.5 miles east of Coffee Creek | MT 81 | 6.5 | Fergus |
| 2027-2028 | 06212 | Drainage Bridge | 11 miles west of Brooks | MT 81 | 30.6 | Fergus |
| 2027-2028 | 06220 | Warm Spring Creek Bridge | 1 mile west of Brooks | MT 81 | 39.2 | Fergus |
| 2027-2028 | 06436 | East Fork Big Spring Creek Bridge | 9 miles southeast of Lewistown | S 238 | 10.6 | Fergus |
| 2027-2028 | 06754 | Hauck Coulee Tributary Bridge | 6 miles southwest of Hobson | S 400 | 5.8 | Judith Basin |
View this table as a printable list of structures.
NOTE: The order of bridges to be replaced and the tentative construction schedule are subject to change due to funding availability, weather, and unforeseen factors.
Map titled “Lewistown Area Bridges – DAR Structures Project.” The map shows central Montana with Lewistown near the center and surrounding communities, including Harlowton to the south and Roundup to the east. Major highways labeled include U.S. 87, U.S. 191, U.S. 12, Montana 80, Montana 81, Montana 238, and Montana 400. A compass rose indicates north.
Bridge replacement locations are marked with colored symbols and labels. Orange markers represent 2026–2027 bridge replacements and blue markers represent 2027–2028 bridge replacements.
2026–2027 bridges (orange markers):
• Dry Wolf Creek Bridge (Structure ID 06209) near MT 81.
• Drainage Bridge (Structure ID 06216).
• Drainage Bridge (Structure ID 06217).
• Drainage Bridge (Structure ID 06219).
• Deadman’s Basin Canal Bridge (Structure ID 06606) south of Lewistown near Harlowton.
2027–2028 bridges (blue markers):
• Coffee Creek Bridge (Structure ID 06206).
• Coffee Creek Tributary Bridge (Structure ID 06207).
• Drainage Bridge (Structure ID 06212).
• Warm Spring Creek Bridge (Structure ID 06220).
• East Fork Big Spring Creek Bridge (Structure ID 06436) southeast of Lewistown.
• Hauck Coulee Tributary Bridge (Structure ID 06754) southwest of Lewistown.
A legend identifies orange markers as 2026–2027 bridges and blue markers as 2027–2028 bridges.
UPN 1027600