Montana Department of Transportation

Main Content


Old Highway 312 Corridor Study

Old Highway 312 Corridor Study logo


The Montana Department of Transportation (MDT) Rail, Transit and Planning Division completed a corridor study on Old Highway 312 (Highway 312) outside of Billings. Highway 312 (X-56788) connects the communities of Huntley, Shepherd, and Worden with Billings. The area has experienced substantial growth in recent years, and the influx of commuters on the system has increased traffic and congestion. The purpose of the study was to develop a comprehensive long-range plan for managing the corridor and determining what, if anything, can be done to improve the corridor based on needs, public and agency input, and financial feasibility. The study was a collaborative process with local jurisdictions, other agencies, MDT, the Federal Highway Administration (FHWA), and the public to identify transportation needs and potential solutions given funding constraints.

The Highway 312 corridor is located in south central Montana in Yellowstone County. The study area extends from its western terminus at the intersection of Highway 312/US Highway 87 to its eastern terminus at the I-94 Interchange near the Pompeys Pillar National Monument. The study area includes a 200-foot buffer from centerline along both sides of the roadway (for a total buffer width of 400 feet) throughout the corridor.

View Study Area

The goal of the study was to assess current and projected conditions in the Highway 312 corridor and identify options to address identified needs. The study analyzed transportation and environmental conditions within the corridor and attempted to minimize the cost of improvement options while considering and avoiding areas of environmental and public concern.