Engineers are finalizing design details for the massive Billings Bypass project, which will connect Lockwood and the Heights with work beginning as soon as spring of 2019.
Project manager Todd Cormier, an engineer with DOWL, gave an update on Tuesday about progress on the Bypass, which has been in the works for years.
The Bypass will add an interchange at Johnson Lane and Interstate 90 in Lockwood and extend a new roadway over Coulson Road and the Yellowstone River.
Connections will then be constructed north on Five Mile Road to Highway 312 and west toward a reconfigured intersection at the confluence of Bench Boulevard, Main Street, Highway 87 and Mary Street.
The first phase of construction is expected to be on Five Mile Road, including a new section of road from Highway 312 to Dover Road and a reconstructed Dover south of that. Groundbreaking is planned for spring 2019.
Cormier said the price tag will be in the range of $75 million to $90 million, making it one of the state's largest bypass projects. Multiple engineering firms are working with the Montana Department of Transportation on the job, with Peaks to Plains Design handling public outreach.
With a finalized environmental impact statement in hand, Cormier said engineers are working on draft construction plans for eventual contractors, finalizing design details and planning for an estimated six-year construction time.
"We're also looking at how best to sequence this project," he said.
Cormier said the bypass provides another Yellowstone River crossing for eastern Billings and Lockwood. And it will alleviate congestion around MetraPark and Main Street, one of the busiest roads in the state.
"Without the Bypass, you could see 11 intersections fail (from congestion)," he said.
One change in the design phase is the addition of a pedestrian route on the Yellowstone River bridge. The path is planned to be about 10 feet wide and separated from traffic lanes.
The bridge is the project's most expensive feature. Another large piece is the new interchange at Johnson Lane, which will link that road with Interstate 90 and the new bypass section to the north.
Engineers decided on a diverging diamond interchange configuration, the first in Montana. A main feature of this configuration is that it reduces the number of chances for vehicle collisions, Cormier said.
"We are going to see a huge improvement to operations out there," he said.
The interchange could also include separate room for pedestrian or bicyclist access in the center.
The intersection at Bench Boulevard, Main Street, Highway 87 and Mary Street will also see a redesign.
One major change is that Bench will no longer connect into Highway 312. Instead, northbound drivers will be directed to the right, onto Mary Street. Those same northbound drivers will have to access the intersection by turning left onto Pemberton Lane and finally to Main Street.
The main Highway 312/Main Street/Highway 87 intersection will be moved northeast a bit to accommodate the bypass.
As the design phase progresses, state officials are beginning to contact residents in the bypass corridor. MDT Billings District Administrator Stefan Streeter said that residents in the Five Mile Road area will get contact first, as that's the initial project phase.
Cormier said engineers will release more information and visualizations of the project in the coming months.