LISBON — Starting next week, commuters in Lisbon can expect a few changes.

The Maine Department of Transportation will begin its project building a new Mill Street bridge Monday. Mill Street will be closed for the duration of the construction, expected to last until Oct. 20.

The department is optimistic about the timeline for the work to be completed.

“The timeline isn’t bad for a bridge replacement,” MDOT spokesman Ted Talbot said. “It will only take one construction cycle. It’s obviously weather dependent. We can move steel in the rain, but paving we can’t do in the rain, but it should be done by mid-October.”

Mill Street traffic will be rerouted on a 2½-mile detour, using Upland Road to connect traffic with Route 196.

“The impact on the commute will depend on the time of day, but probably 10 or 15 minutes,” Talbot said. “There is a minimal business impact, which is something we look for. All of the businesses will be open.”

The replacement of the bridge, which was built in 1926, is a $1.4 million project. It includes 400 feet of road construction in addition to the bridge. While the work is ongoing, the town is expected to install upgrades to water and gas utilities.

The new bridge is estimated to last nearly 100 years.