Montana Department of Transportation

Malcolm “Mack” Long, Director


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Main Content

Public Involvement

Lost Trail Improvements

Project Overview

image of paving

The Montana Department of Transportation is undertaking a project near Lost Trail Pass this summer to extend the life of the roadway through pavement preservation. The Lost Trail Improvements project begins at the Idaho border and extends north along US-93 for 8.9 miles. Work is expected to be begin in mid-June and will be substantially complete by August.


By the time a roadway shows signs of wear and tear it’s often to late. That’s why the Montana Department of Transportation invests in preventative maintenance through its Pavement Preservation Program. Pavement preservation projects are designed to restore the overall condition of the roadway without adding capacity or otherwise altering the roadway. Projects are nominated on a regional basis roughly two years before the start of construction.

The Lost Trail Pass Improvements project was nominated as part of MDT’s regular pavement preservation program. The project involves a full width mill and fill along 8.9 miles of US-93 immediately north of the Idaho border. In addition to surface improvements, new sections of updated guard rail and shoulder rumble strips will be installed in select areas.

What to Expect

MDT is committed to working with local stakeholders to minimize construction impacts on industry and the traveling public. Drivers should expect single-lane closures during milling/paving activities with pilot cars and flaggers to direct traffic.

Because this is a construction project, the traveling public is asked to prepare for delays of up to 15 minutes and reduced speeds of 35 mph. Members of the public can find timely detour and delay information here (look for US-93).

Respect the Cone Zone

Construction crews in Montana spend their days working a short distance from fast moving vehicles, and while they make every effort to work safely, they are counting on you to pay attention, slow down and be careful as you pass through a work zone. Remember to leave plenty of space between yourself and workers and equipment and wait to speed up until you see roadway signs indicating its safe to do so.

Project Map

Map of Lost Trail Pavement Preservation project Click to view a larger image.