(HELENA) After a break over the winter, work will resume next month on a project to replace two bridges on Interstate 15 in Helena.

Sletten Construction will start work Mar. 6 on the next phase of the Capital/Cedar Interchange project. Representatives from Sletten and the Montana Department of Transportation held a public meeting Thursday night to lay out the schedule for this year’s construction.

Crews will demolish and rebuild the southbound I-15 bridge over the Montana Rail Link tracks. The northbound bridge was rebuilt last year.

“This year, essentially, we’re going to do a twin to what was done last year,” said Craig Shanholtzer, Sletten’s project superintendent.

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The current bridge was built in 1960. The new structure will be twice as wide – 65 feet instead of 28 feet – and will contain an automatic de-icing system. Crews will also build a “sound wall” along the bridge’s western edge, to protect nearby houses from highway noise.

During construction, one lane of southbound traffic and two lanes of northbound traffic will share the new northbound bridge. It’s a similar arrangement to last year, but with a much wider roadway.

“It was narrow last year with our two-way traffic, but it went well, flowed well,” Shanholtzer said. “So this year, we’re going to have essentially more than double the room.”

Boulder Avenue will be closed 24 hours a day while crews demolish the current bridge. That closure will run from Mar. 6 to Apr. 22. After that, Shanholtzer says there could be occasional daytime closures throughout the spring and summer.

The new bridge is scheduled to be completed by October, but Sletten will return for several weeks in summer 2018 to finish sealing work.

Overall, Shanholtzer expects the work to go smoothly, with relatively light impacts on drivers.

“We just ask that everybody, again, be patient with us,” he said. “Safety’s of the utmost concern.”