PORTLAND — The Maine Department of Transportation will present plans for a new Martin’s Point Bridge at 6 p.m. today in the State of Maine Room at City Hall.

The $23.5 million structure will replace the Route 1 bridge that crosses the Presumpscot River between Portland and Falmouth.

The new bridge will be designed and built by CPM Constructors of Freeport and VHB of Watertown, Mass., a team that submitted the least costly of five competitive proposals.

Built in the early 1940s and overhauled in 1991, the bridge is a major link in the local transportation grid, carrying about 15,600 vehicles daily.

The new structure will retain two travel lanes and feature enhanced accommodations for bicyclists, pedestrians and fishermen.

The new bridge will be built right next to the existing one, with a little overlap at each end, so two-way traffic will be maintained throughout construction, transportation officials said.

No private or public properties will be taken for the new bridge, but some temporary easements will be needed during construction.

Work is expected to start as early as this fall and be completed by December 31, 2014.

The project includes removal of the old bridge when the new bridge is finished.