US 191/MT 64 Optimization Plan logo

trucks driving on bridge

Optimization Plan Overview

US Highway 191 (US 191) and Montana Highway 64 (MT 64) connect year-round tourism, commerce, and commuters near Big Sky and the surrounding communities. In 2020, the Montana Department of Transportation (MDT), in partnership with the Federal Highway Administration (FHWA) and Gallatin County, completed the US 191 Corridor Study to assess the roadway between Four Corners and Beaver Creek Road, just south of the intersection with MT 64. The purpose of the study was to develop a comprehensive long-range plan for managing the US 191/MT 64 corridor and to identify feasible improvement options to address the needs of local communities and the traveling public.

As part of the US 191 Corridor Study, MDT identified over $370 million in improvement options to enhance safety and current traffic operations within the corridor. To optimize impact, a cross-functional project team was formed to identify efficiencies, secure funding, enhance safety, and improve traffic operations. This includes prioritizing improvements that will benefit the traveling public while managing the corridor's limitations and securing funding.

A Collaborative Approach for Informed Decision Making

Several stakeholders have a vested interest in improving the US 191/MT 64 corridor, which is why a Context Sensitive Solutions (CSS) approach was implemented. CSS balances stakeholder interests and community feedback with US 191 Corridor Study data to help shape priorities and determine next steps. The project team has invited local community interest groups, landowners, and the public to share feedback about potential corridor improvements. CSS ensures that decisions are thoughtfully considered from a variety of perspectives.

Project Needs and Objectives

Potential improvement needs have emerged through the CSS process, which considered existing and future conditions, local plans, and input from stakeholders. Key themes and potential considerations include, but are not limited to:

  • Enhance safety:
    • Reduce fatalities and serious injuries in support of MDT’s Vision Zero goal.
    • Improve roadway elements to meet current design standards.
    • Reduce animal-vehicle collisions.
    • Reduce roadside hazards.
    • Reduce the frequency and severity of crashes.
  • Improve traffic operations:
    • Accommodate existing and future travel demands.
    • Provide reasonable access for recreation.
    • Upgrade non-motorized mobility and accessibility.
    • Improve corridor reliability.
    • Accommodate wildlife movement.
  • Other considerations:
    • Impacts to environmental resources.
    • Temporary construction impacts.
    • Funding availability.
    • Design and construction timeline.
    • Maintenance costs and responsibility.
    • Local and regional planning.

What is the Team Working on Now?

MDT partnered with HDR on project design, and the design team is currently collecting and analyzing data, developing alternatives, and meeting with stakeholders. Initial areas of focus (subject to change and periodic updates) are:

INTERSECTION OF US 191 WITH MT 64
The design team is finalizing possible alternatives at this location that would maintain access to local businesses and minimize impacts to the Gallatin River.

LAVA LAKE ACCESS
Lava Lake Trailhead access, including the bridge that carries US 191 traffic over the Gallatin River, has been identified as an area in need of improvement.

PULLOUT LOCATIONS
The design team is reviewing existing pullout locations along US 191 and MT 64 to improve accessibility for the traveling public and emergency responders.

PASSING LANES
The design team is exploring options to provide additional passing opportunities.

WILDLIFE AND WATER QUALITY CONSIDERATIONS
Water quality and wildlife crossing improvements will be taken into consideration along the corridor. MDT is partnering with Montana Fish, Wildlife, and Parks (FWP), as well as non-governmental organizations (NGOs) in the area to determine solutions.

Project Implementation and Next Steps

Team members will continue meeting with stakeholders and local officials to understand community needs, evaluate funding opportunities, and develop design and construction timelines for potential projects. Once design and construction timelines have been established, updates will be shared on this webpage.

For More Information
If you have any additional questions, please contact:

Kristine Fife
Big Sky Public Relations
406-475-5651 | Email

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