MassDOT to Complete Sagamore & Bourne Bridge Replacement by 2037

The reconstruction for two Cape Cod bridges should be mostly finalized by 2037, according to state officials.

The Boston Globe reported on Tuesday, Feb. 3, that “traffic will be on a new bridge over the Cape Cod Canal” by 2033, and that 2037 “is when we expect both new bridges over the Cape Cod Canal to be built and open for traffic.”

On Jan. 20, MassDOT shared an updated timeline at an open house. 

According to the timeline, by fall 2033, “all traffic” will be open on a “new southbound bridge.” The “existing Sagamore Bridge [will be] demolished” that winter. The “northbound bridge span float-in” work is scheduled for spring 2036. “All traffic in the final configuration” will be set by winter 2036-2037.

The Sagamore and Bourne bridges, opened in 1935, have long been considered functionally obsolete. The Army Corps of Engineers had recommended replacement for the bridges in 2020. Securing funding for the Bourne Bridge remains a hurdle.

According to the Globe, the Sagamore bridge replacement is estimated at $2.1 billion. Replacing both bridges would total roughly $4.5 billion, although funding for the Bourne Bridge component has not yet been secured.

Officials began using eminent domain in March 2025 to acquire 13 homes and seven other vacant properties to clear space for the Sagamore Bridge. Four deals with residents were expected to close in January, and the rest will occur by the year's end. 

A MassDOT spokesperson told the Globe that the state is also making 17 “partial acquisitions,” in which the state will seize a portion of a larger property. The cleared neighborhood will serve as a staging space for construction equipment and could later become containment basins for stormwater runoff from the new bridge.