Montana Department of Transportation

Malcolm “Mack” Long, Director


View the Governor’s Coronavirus Task Force site for more information.

Main Content

Active Project - Highway 287 - Diehl Ranch Dr to Spokane Creek Rd

Highway 287 - Diehl Ranch Dr to Spokane Creek Rd logo

Highway 287 - Diehl Ranch Dr to Spokane Creek Rd

Project Overview

The Montana Department of Transportation (MDT) is proposing to reconstruct US 287/US 12, east of East Helena. The new road will consist of two travel lanes in each direction, a center turn-lane, a right-turn lane from Spokane Creek Road, and eight-foot shoulders. The roadway will be completely reconstructed, including grading, resurfacing, pavement markings and signage.

U.S. 287/US 12 is an important state highway for traffic between I-15 in Helena and I-90 in Three Forks and for surrounding communities. This roadway experiences increasing usage that it was not originally designed to accommodate. The Highway 287 project will provide US-12/US-287 passing and turn lanes for a section of roadway beginning just east of Diehl Ranch Drive and ending at milepost 55.9, east of Spokane Creek Road. This project is in Lewis & Clark and Jefferson Counties.

Right-of-way acquisition and utility relocation will be required. MDT staff will contact all potentially affected landowners prior to construction regarding property acquisition and temporary construction permits. Residents may start to see workers surveying the area in early 2020.

Construction is tentatively planned for 2021. Drivers may experience limited delays up to 15 minutes and should expect lower travel speeds during construction. One travel lane in each direction will be maintained during construction.

Project Limits Map

Highway 287 - Diehl Ranch Dr to Spokane Creek Rd Project Limits Map
View PDF Highway 287 - Diehl Ranch Dr to Spokane Creek Rd Project Limits Map

How can I stay informed?

Big Sky Public Relations has been hired by the Montana Department of Transportation to ensure we can answer your questions as quickly as possible and to improve our ability to share information.

Refer to this site for upcoming public involvement notices as they become available. Notices will also be distributed to those on the project's mailing list. MDT encourages members of the public to join the project's mailing list by submitting contact information to Takami Clark .

Information will be published on this website, in local media venues, and via newsletters throughout the project development process.

UPN 8684000