THE MASSACHUSETTS DEPARTMENT of Transportation issued an unusual press release Tuesday evening indicating the agency is preparing to spend $75 million shoring up the crumbling elevated section of the Turnpike as it runs between Boston University and the Charles River.

MassDOT said the repair work was needed for the “near-term safety of the viaduct” and to set the stage for the selection “later this year” of the preferred design for the I-90 Allston project.

The press release, issued at 7:30 p.m., gave no precise date for the selection of the preferred design and was vague about what options were still on the table. The release did note that the MBTA is exploring options for a commuter rail repair facility to the south of the Turnpike, which officials in the past have said would only be needed if certain options were pursued.

The I-90 Allston project, expected to cost more than $1 billion, would replace the crumbling viaduct as well as the Turnpike, Soldiers Field Road, and commuter rail tracks as they run through the throat, a narrow strip of land between BU and the Charles. As most envision it, the project also would straighten the Turnpike, build a new MBTA station, and set the stage for Harvard University to build a new neighborhood on a huge swath of cleared land in the area.

Former transportation secretary Stephanie Pollack never reached consensus on how to design the project. In November, she indicated a handful of options were on the table for the throat: replacing all of the transportation elements as they are currently situated, with the Turnpike elevated; putting the Turnpike and rail elements at ground level and elevating Soldiers Field Road; and putting all of the transportation elements at ground level.

The city of Boston, transportation advocates, and business groups coalesced behind putting all the transportation elements at ground level and have lobbied hard for that approach. Pollack also floated a Plan B in November, which entailed rebuilding just the elevated section of the Turnpike and leaving any other work for some future date.

Pollack in November indicated that in her mind the design choice for the complete project had come down to two options: replacing all the transportation elements as is, or putting them all at ground level.

She said the chief advantage of the at-grade approach was that it removes an elevated highway between the neighborhood around BU and the Charles River. She said, however, that the at-grade design would have a much greater impact on the Charles River, both during construction and once the work is completed, and could be difficult to permit. She also said the at-grade approach would end up costing about $300 million more because building it would require the temporary shutdown of a rail line allowing access to a commuter rail maintenance facility on the north side of the commuter rail system; with access to that facility shut off during construction, Pollack said, the MBTA would need to build a new maintenance facility to the south of Boston.

The press release issued Tuesday evening indicated the MBTA was pursuing a maintenance facility to the south of Boston, suggesting at the very least that such a facility was not going to be an obstacle to building everything at-grade.

Pollack left for a job with the Biden administration in January and was replaced by one of her aides, Jamey Tesler, who is serving as acting secretary. Tesler has said little about the Allston I-90 project, which has prompted speculation about whether he has a different approach.

In its press release, MassDOT said the repair of the elevated section of the Turnpike will start in early 2023 and focus on shoring up the structural steel and the concrete.

The supports for the Massachusetts Turnpike viaduct are in tough shape.

“Most of the work will occur underneath the viaduct, and it is anticipated there will be minimal disruption for rail and roadway commuters with some night and weekend lane takings expected,” the press release said.

The money is expected to come primarily from rent being paid by developers building projects above the Turnpike in the Back Bay.

“By accelerating this first phase of the multi-modal project, MassDOT is ensuring the near-term safety of the viaduct and reducing the risk of future emergency repairs that would impact rail and road users. Additionally, accelerating this work better positions the Commonwealth to take advantage of any additional federal funding or programs, while reducing the permitting risks of the construction phasing and operations of the larger, long-term multi-modal project,” the press release said.

Rick Dimino, the president and CEO of the business group A Better City, which favors the at-grade design approach, said he welcomed MassDOT’s announcement.

“The state’s strategy represents a reasonable investment of state and federal funds, as the Allston viaduct will need to be safe and operational during construction of the broader I-90 Allston multimodal project to provide for important traffic mitigation. Additionally, the long-needed creation of a new south side rail maintenance facility will help facilitate improved commuter rail operations and have the potential to minimize long-term construction impacts. This initial investment must be part of a broader financing strategy that leverages federal infrastructure funds to realize the full I-90 Allston multimodal project, including the new intermodal West Station on the Worcester/Framingham Commuter Rail Line,” Dimino said in a statement.