In the wake of widespread pushback against earlier proposals, state transportation officials floated a new design Monday for a landmark Allston infrastructure project that they will consider alongside two other options as a key deadline approaches.
The more than $1 billion Allston Multimodal Project may represent the most significant highway work in Massachusetts in a generation, but planning for up to a decade of construction, accomplishing goals for four different modes of travel, and minimizing impacts on the hundreds of thousands of daily commuters that pass through the narrow stretch of land connecting Boston to the west has been fraught with difficult choices.
Deliberations have been underway for years about how best to balance the project's goals of replacing the structurally deficient viaduct carrying the Turnpike, straightening a curved section of the road, allowing for construction of a commuter rail West Station and freeing space for pedestrians and neighborhoods.
Because the 12 lanes of crowded roadway, commuter rail tracks and walking paths are crammed into only 204 feet of space between Boston University and the river, construction will impose major disruptions on some if not all of the modes of travel through the area.
A new proposal Transportation Secretary Stephanie Pollack detailed Monday attempts to respond to criticism that environmental and neighborhood groups lobbed at everything from the project's impacts on the Charles River to the delays it might cause on the commuter rail.
The option that Pollack unveiled Monday would scrap any plans to push a portion of Soldiers Field Road onto the river itself, either temporarily or permanently, and avoid a years-long closure of the Grand Junction Bridge that would force the MBTA to build a $300 million maintenance facility.
Construction could be completed in about six and a half to eight years, according to Pollack's presentation, less than the maximum of 10 years estimated in other plans.
Under the proposal, MassDOT would replace the structurally deficient viaduct carrying the Massachusetts Turnpike between Boston University and the Charles River with a smaller new viaduct that still supports eight lanes of travel.
Commuter rail trains would run underneath the highway, while Soldiers Field Road would be built at ground level, separated from the river by pedestrian and bicycle paths.
Project leaders are in many ways attempting to thread a needle with their plans. The area, often referred to as the "throat," contains eight lanes of the Turnpike, four lanes of Soldiers Field Road, commuter rail tracks and a pedestrian path in only about 204 feet from the edge of BU to the riverbank.
Pollack said during a Monday joint meeting of the MassDOT Board of Directors and MBTA Fiscal and Management Control Board that the plans respond to "the two most important questions that have been put on the table since the public comment period."
"Those two questions are: can you build it any faster, and is there a way to build without any impact on the Charles River?" she said. "The answer to both of those questions is yes."
Some earlier proposals suggested using floating structures on the Charles to carry portions of Soldiers Field Road during construction or filling in a section of the river to extend the roadway, but those drew opposition from advocates and, Pollack said Monday, from the Baker administration's environmental secretariat.
The department has not yet selected a final design, and officials will compare the new option to two others: one that would place rail lines, the Turnpike, Soldiers Field Road and a single pedestrian and bike path side by side stretching more than a dozen feet into what is currently the river, and another that would elevate Soldiers Field Road onto its own viaduct and build the Turnpike beneath it at grade level.
Cost estimates were not immediately available Monday, but the department said an earlier version of one option placing Soldiers Field Road on a viaduct would carry a roughly $1.1 billion price.
While Pollack did not endorse the new design Monday, she noted it could accomplish the project's main goals — replacing the deficient viaduct, straightening a long curved section of the Turnpike, allowing for construction of a commuter rail West Station, and more — at far more favorable ratings than the other two.
In July, the department will submit a scoping summary report as part of the mandatory federal review of the project with additional information on the three options. Pollack said Monday that 45 days after that, federal and state agencies will need to determine if they concur on an alternative.
Without concurrence, the department "would have to have a pretty serious discussion about how and if we want to proceed" with the project or if MassDOT should instead pursue a "no-build" repair of the deficient viaduct, Pollack said.
"The issue is that the time has come to make a decision, not to study alternatives in perpetuity, but to roll up our sleeves and begin after six years the process of planning for the construction and mitigation of the Allston Multimodal Project," she said.
Only two members of the boards responded to Pollack's presentation. MassDOT Board Vice Chair Betsy Taylor warned that the project stems from a "serious maintenance problem" and "serious safety problem" at the existing viaduct and pledged that she will push for repairs if stakeholders cannot find consensus soon.
Former Braintree Mayor and MassDOT board member Joe Sullivan said he viewed the no-build option as a "nonstarter."
"This is a forever decision, and I hope that we will be bold in that decision-making come the fall, because it would be transformative, it would in many ways create not only economic opportunities along that corridor, but also just a new vision of a plan that will be with us for 100 years-plus," he said.