Drivers who use the Johnson Lane exit off Interstate 90 in Lockwood will spend the next few years watching it turn into something no other place in Montana has: a diverging diamond interchange. The Montana Department of Transportation announced on Oct. 23 that it had awarded the contract for the project to Riverside Contracting Inc., and preliminary work is already underway.
The interchange is the fourth of six segments in the Billings Bypass, the long-planned route meant to link I-90 on the east side of Billings with the Heights north of the Yellowstone River. Three segments are finished. The Johnson Lane rebuild is the piece that ties the bypass into the interstate.
A design that sends traffic to the left
In a diverging diamond, traffic on the road crossing over or under the freeway briefly switches to the left side of the road between two signalized crossovers. That sounds alarming, but the point is to let drivers turning left onto the interstate ramps do so without crossing oncoming traffic. Fewer conflict points generally means fewer serious crashes and shorter waits at signals.
The design has spread across the country over the past 15 years, from Missouri, where the first one in the U.S. opened in 2009, to Utah, Idaho and dozens of other states. Montana has never built one. Johnson Lane will be the first.
“We’re excited to bring this new interchange to Montana because of its many operational and safety benefits,” MDT Billings District Administrator Mike Taylor said in the department’s announcement. “The Johnson Lane DDI will help improve current traffic operations while accommodating future demand and supporting continued growth in the greater Billings area.”
MDT acknowledges the pattern may feel strange at first. Directional signs, signals and pavement markings are meant to guide drivers through, and the department has posted a video simulation of the Johnson Lane DDI on the project website so people can see how it will work before they drive it.
Timeline: three building seasons
Utility relocation is the first step and is happening now. Construction on the interchange itself is scheduled to begin in spring 2027 and run through three construction seasons, wrapping up in summer 2029.
The first two seasons will focus on rebuilding the I-90 bridges over Johnson Lane, which need extra width for the new layout, along with the roadwork around them. Improvements south of the interstate are expected to be finished first, with work north of I-90 in the second season. The third season is for final paving.
The work goes well beyond the ramps. Crews will also reconstruct parts of North Frontage Road, Old Hardin Road, Cole Street and Becraft Lane, add new traffic signals at Cole Street and Old Hardin Road and at Johnson Lane and North Frontage Road, and build a shared-use path for people walking and biking, with sidewalk and ADA upgrades on nearby streets.
For Lockwood residents, the payoff is better connections in a part of Yellowstone County that has grown quickly while its road network has lagged behind. Johnson Lane carries a mix of commuters, freight trucks heading to and from the interstate, and traffic from the commercial strip and neighborhoods around the exit. Anyone who has waited through a backed-up light near the ramps knows the problem.
Living with the construction
Three seasons of work at an interstate exit means detours, lane shifts and slower trips. “Projects of this size require changes to how people travel through the corridor both during construction and once the DDI is in place,” Taylor said. He urged people to sign up for the project’s email and text notifications and check the website often.
The project team is taking questions now. Residents and businesses can reach the Billings Bypass team by email at billingsbypass@dowl.com or by phone at 406-294-9668. Updates and the sign-up for alerts are on MDT’s Billings Bypass page.
Where the bypass stands
The Billings Bypass has been in the works for well over a decade. Its goal is to give drivers a way to move between I-90 and the Billings Heights without going through downtown Billings or squeezing across the existing Yellowstone River crossings. With three segments done and the interchange now under contract, the remaining work is mostly about tying the pieces together.
The Johnson Lane interchange is also likely to become a test case. If a diverging diamond works well in Lockwood, with its mix of semis, winter driving and local traffic, other Montana cities may see the design proposed for their own congested exits.
For now, the only visible sign of the change is the utility work along the roads near the exit. The heavy equipment arrives in the spring of 2027.