Presentation to joint county commission includes safety projects, traffic flow improvements slated for summer 2026
By Jack Reaney SENIOR EDITOR
The Montana Department of Transportation continues to demonstrate greater attention to U.S. Highway 191, the heavily driven and dangerous one-lane highway connecting Big Sky and Bozeman.
At the Madison-Gallatin Joint County Commission meeting held in Big Sky on Wednesday, May 14, MDT Butte District Preconstruction Engineer Brandon Jones discussed plans for the highway, including the Lava Lake renovation first presented in October 2024, as well as the potential roundabout at the intersection of U.S. 191 and Montana Highway 64 in Big Sky—currently awaiting the outcome of a federal grant application—and other proposed improvements including passing lanes and turnout signage.
Jones said MDT has been frequently scoping out damaged areas along U.S. 191 this spring.
“Obviously, as you’re driving up and down from Bozeman to Big Sky, you’re seeing some pretty significant pavement distress, and some sub-grade distress, so we’re looking to remedy that as much as we can,” Jones said in his introduction of MDT’s “Big Sky North” project to make improvements to U.S. 191 during the 2026 construction season.
When MDT conducted a preliminary field review in August 2024, the road was in “pretty decent shape… but obviously that’s changed throughout the winter,” Jones said.
He added that although MDT did not anticipate significant repairs until recently, MDT added the Big Sky North project into its fiscal year 2026 tentative construction plan. TCPs outline five-year priorities to maximize budget efficiency, and Jones said the Big Sky North project is slated for construction in 2026.
“It’s not a secret, I’m sure that you guys are well aware that 191 has fallen into disrepair, especially following this last winter cycle,” Jones said. He listed problems including erosion between guardrails and the Gallatin River and snowmelt saturation beneath the pavement. “Through freeze-thaw, and the increased traffic loads that you guys are seeing down there, you know, we obviously saw that roadway blow apart pretty significantly over the winter season.”
MDT will evaluate opportunities to improve drainage and replace sections of worn pavement and damaged guardrail as part of its upcoming project.
Plans include passing lanes, turnout messaging, Spanish Creek bridge
Larger scale upgrades are in the works, too, including passing lanes to allow faster traffic to move past slower vehicles.
MDT nominated four areas for passing lane construction: a northbound lane just north of the 191/64 intersection; a southbound lane at Portal Creek; a northbound lane in the Hellroaring and Storm Castle area; and a southbound lane near Spanish Creek.
Jones said MDT will include several safety features to mitigate the hazards created by passing lanes where the additional passing lane merges back into one lane of traffic.
Currently, the only passing lane between Big Sky and Four Corners is the northbound lane at the mouth of the Gallatin Canyon, where drivers often attempt to pass multiple vehicles at a high speed before lanes merge, all in the face of oncoming vehicles heading south.
One safety feature is the center-line rumble strip, Jones said, which mitigates head-on collisions by roughly 90%, according to Federal Highway Administration studies.
Another design consideration is ensuring a proper length of “transition taper” to allow a smooth merge back to one-lane traffic.
Another potential improvement to traffic flow, MDT is working to improve the turnouts along the narrow Gallatin Canyon route.
“We’re looking kind of outside the box of what MDT has usually done when installing these turnouts, to make it very obvious that these are not recreational turnouts… but a location that’s used for the slower traffic to get off of the roadway and allow faster traffic to pass them,” Jones said.
In Big Sky, MDT is evaluating designs to improve the 191/64 intersection—since MDT announced the project in January 2024, every iteration of preliminary design has shown some form of a roundabout.
Jones noted that if MDT moves forward with the roundabout design, it would be designed to accommodate large trucks and trailers.
“In this conceptual layout, this is a roundabout. We’re still working through some of the layout… just a little brief glimpse of the conceptual layout that we’re currently considering,” Jones said.
The project’s construction timeline will depend on whether MDT receives a federal BUILD Grant from the U.S. Department of Transportation, with a decision anticipated by the end of June.
Another upcoming project is the Spanish Creek bridge replacement. Since October 2024, MDT has been designing a replacement to ensure the new bridge design accommodates wildlife movement while avoiding cultural site impacts, according to a March press release from MDT.
Construction is anticipated to begin in 2029, and funding for design and construction has already been allocated for the Spanish Creek bridge project.
Timeline uncertain for Lava Lake project
Jones showed three renderings that expanded on early designs shown at the most recent joint county commission meeting in October 2024.
Primarily intended to replace an aging, curved bridge, the project also aims to flatten the road curves and improve pedestrian access to the Lava Lake trailhead—plans now show a pedestrian access bridge over the Gallatin River between the primary parking lot and the popular trailhead.
The three design options include varying degrees of rock cut required and bridge construction work. Jones indicated the third option “optimizes the geometry” to limit bridge construction and rock excavation required.
Jones said the third option also most closely resembles the current layout, and “there’s probably a little bit of wisdom” to maintaining the curvature which necessitates a slower driving speed around a “pretty treacherous” curve.
MDT still has not included Lava Lake improvements in a tentative construction plan, and a construction timeline remains uncertain.
“That one’s going to be the most difficult one to fund, quite frankly,” Jones said, adding it will likely cost between $70 and $80 million, and MDT is currently going all-in on the 191/64 intersection in terms of federal grant requests.
Community feedback
During public comment, community member Tallie Lancey noted the helpfulness of the webcam at mile marker 55 (Karst) to inform travelers about traffic volume in the Gallatin Canyon, and asked if it would be possible to add one at the 191/64 junction—Jones said MDT would take the request into consideration.
Jones later added it would be “a good return on investment” to create a live-updating website to communicate expected travel times, potential accident information, and other notices regarding U.S. 191—currently, the best resource for immediate updates is an informal crowd-sourced Facebook page.
Big Sky Resort Area District board chair Kevin Germain said Big Sky’s biggest challenge has been workforce housing, an area that recently took “a quantum leap forward” with the passage of the Cold Smoke Bond.
“I would say our number two community issue is 191 and 64, and this is something that we really are leaning into… This is where we need your help the most right now,” said Germain, addressing the commissioners from both counties.
