Two new bridges, one to replace the Bourne and one to replace the Sagamore. Both are tied-arch designs, like the existing bridges in shape. Wider lanes, safer separated paths for walking and biking, modern lighting. The basic idea is “same place, same height, but better.”
The basic shape
Each new bridge has a big curved arch above the road, like an upside-down U. The road hangs from the arch using thin steel cables.
This shape doesn’t need supports in the middle of the canal, so big ships can still pass underneath.
The current Bourne and Sagamore are tied-arch bridges too. The new ones use the same basic idea with modern materials and bigger spans.
What’s the same as today
- Same height above the canal. Boats won’t notice a difference.
- Same general spot. Each new bridge sits next to its old one.
- Same routes feeding it. Sagamore stays on Route 6. Bourne stays on Route 28.
What’s new and better
- Wider lanes for cars and trucks. The existing lanes are narrow by modern standards.
- Shared-use paths separated from cars by a barrier. Wide enough for walking, jogging, biking, strollers and wheelchairs.
- Better lighting, better drainage, better steel.
- Bridges built to handle modern truck weights without daily patching.
Walking and biking
Today, the Bourne sidewalk is one direction at a time when it’s open at all. Crossing on foot in wind or rain is uncomfortable. The Sagamore sidewalk is similar.
The new bridges have shared-use paths separated from cars by a real barrier. Both paths connect to the existing canal trail on each side. Once both new bridges are done, you’ll be able to bike from Falmouth to Sandwich on dedicated paths, including across the canal.
How they get built without closing the old ones
Workers build each new bridge in the space next to the old one. The big arch sections are built at a shipyard somewhere else. When each section is finished, barges float it down the canal to the bridge site. Cranes lift the spans into place.
The old bridge stays open the whole time. When the new one is ready, traffic shifts to the new bridge. Then the old bridge comes down.
When will it be done?
- New Sagamore southbound side: opens fall 2033.
- New Sagamore northbound side: opens 2036.
- New Bourne: about a year behind, finishing in 2037.
For project status and timeline, see the Project Tracker. For the longer story on the rebuild, see The Cape Cod Bridges Replacement, Explained.