MassDOT Kicks Off Study for Tobin Bridge Replacement, Looking at Tunnel as Option

Massachusetts transportation officials have started planning to replace the 74-year-old Tobin Bridge. They're considering building an underground tunnel to connect Boston and Chelsea instead.

"Repairs are not a permanent solution, that's why we are releasing the RFP for our planning and engineering team to do a study, which is intended to help us think and gather perspective on the bridge's future while it is still in good working order," said Acting Transportation Secretary Monica Tibbits-Nutt to Roads & Bridges.

Around 87,000 vehicles travel across the Mystic River on Route 1 each day. The bridge is also crucial for public transportation, with MBTA's 111 bus carrying 7,000 riders daily.

The study will continue through summer 2026. Flooding is a big worry - experts say the Mystic River will rise 2.4 feet by 2050, and 4.2 feet by 2070. Storm surges could push water levels up 10 feet.

Quick fixes are getting expensive. MassDOT recently spent $109 million just to repair the existing bridge.

The replacement needs to do more than just handle cars. They want to add walking and biking paths, and special lanes for buses - features the current bridge doesn't have.

Many groups will help decide what happens next. City officials from Boston and Chelsea are working with port authorities, Army engineers, and the Coast Guard.

The environment is a top priority. Teams will monitor air quality impacts and effects on local wildlife. They're also trying to fix problems from the past, when the original bridge split neighborhoods apart.

We'll see the complete plans and recommendations by 2026. While construction dates aren't set yet, drivers should expect some disruption when work begins.