The Massachusetts Department of Transportation is rebuilding a key section of the Massachusetts Turnpike in Allston, and after much debate, they’ve selected a design concept for the $1.1 billion project. Many stakeholders have said they like what they see, but it’s the stuff that’s missing that has them concerned.

Every day, around 150,000 drivers on the Mass. Pike make a sweeping arc at the Allston interchange around an abandoned rail yard. This elevated section of the highway then squeezes into a narrow strip of land between the Charles River and Boston University, known as “the throat.”

The magnitude of the project to straighten this stretch of highway, and the disruption it will cause, is being compared to The Big Dig. But it needs to happen — the viaduct was built in the 1960s and its age shows. Experts say it won't be safe for much longer.

MassDOT’s plan not to rebuild the viaduct and instead to rebuild this stretch of the highway at ground-level has been met with nods of approval.

“It was a collective victory,” said Rick Dimino, president of A Better City and the former commissioner of transportation for the city of Boston.

“We were happy to see that the state made the correct choice,” said Alexandra Schluntz, a Yale public interest fellow at the Conservation Law Foundation.

“MassDOT Secretary Pollack made a very good decision,” said Harry Mattison, chair of the strategic planning committee of the Charles River Conservancy. “This hulking, old, rusty, eight-lane highway viaduct is going to be torn down and the Mass. Pike is going to be built flat on the ground, at-grade.”

A view of the Massachusetts Turnpike, Storrow Drive and the path along the Charles River from the Boston University Campus in Boston.
Meredith Nierman WGBH News

However, Mattison, who serves as a community member on the project's task force, is quick to caution that “there are lots and lots of details to work out.”

MassDOT hasn't released any renderings or maps of its plan, but here's what we do know: As Mattison said, the Pike will be taken off its old concrete pedestals and placed on ground-level. The portion of Soldiers Field Road that currently runs alongside it will be elevated above the Pike.

There will, theoretically, also be room for a future commuter rail station, some additional space for walking along the river, and a whole chunk of land owned by Harvard University will be newly available for development.

Read more: Mass. Pike In Allston Will Be Rebuilt At Ground Level, Pollack Says

After decades of the highway walling off Allston, Mattison said he wants to ensure that in the new design, residents like him will be able to enjoy the river.

“It is an amazing opportunity to transform something that right now is a mental and physical dead-end,” Mattison said.

He said he wants pedestrian and bike bridges that take people over the highway to the river. And, along the river path, he wants protection from the noise and pollution of the highway. Images released a few months ago of possible designs, which have been circulating online since the announcement of the design concept, show nothing more than the current knee-high guard rails between bike lanes and speeding traffic.

“You have to be able to use the park and the paths and not feel like you're riding your bike on the highway,” Mattison said.

Others who also generally like the plan said they are worried about another facet of the outdoors: The state's legal obligation to protect it.

“The state is only allowed to use this land if they minimize all negative impacts to the land," said Schluntz, of the Conversation Law Foundation, about the land along the Charles River.

Schluntz also said she wants to see more detailed information from MassDOT about the project's environmental impact. For example, she pointed to flooding, something that's projected to get worse with climate change. Schluntz said MassDOT’s environmental analysis was “more focused on flooding on the project and, unfortunately, didn't go into detail on flooding for the entire watershed and community.”

Schluntz said if MassDOT does not do a more detailed environmental analysis in the next phase of planning, there could be legal recourse.

MassDOT said in a statement that they have "complied with the appropriate laws regarding environmental reviews and permitting” and that they selected the design they did “partly due to environmental considerations.”

MassDOT is holding a public meeting on Jan. 23 where they say they'll present a roadmap for the roadwork and address residents' questions and concerns.

This story has been updated to correct the spelling of MassDOT Secretary Stephanie Pollack's name.