Pollack outlines yet another ‘throat’ option

TRANSPORTATION SECRETARY STEPHANIE POLLACK on Monday proposed a modified rebuild of the existing Massachusetts Turnpike and other transportation infrastructure in the narrow 204-foot space between Boston University and the Charles River as a way of avoiding any incursion into the Charles River and speeding up construction of a new I-90 Allston interchange.

Pollack’s proposal calls for rebuilding the existing eight lanes of the elevated Turnpike viaduct, which is crumbling, but shrinking the highway a bit and moving it closer to BU. The elevated viaduct would be located above four railroad tracks and next to four lanes of Soldiers Field Road and new, separate bike and pedestrian paths along the Charles River. A north-south pedestrian and bike connection between Commonwealth Avenue and the Charles River could be added by running a bridge below the Turnpike but above the railroad tracks and Soldiers Field Road.

The section of the Turnpike on the narrow strip of land between BU and the Charles River is just one element of a much larger $1 billion project to straighten out the Turnpike as it moves through Allston and to make way for a new neighborhood being developed by Harvard University and anchored by a new MBTA station called West Station.

The narrow strip of land, often referred to as the throat, has preoccupied planners who have struggled to find a way to rebuild the Turnpike and all the other infrastructure in the area while keeping east-west vehicle and commuter rail traffic moving during a construction period expected to last anywhere from 6 to 10 years.

As they have in the past, many advocates for various configurations pressed Pollack not to choose a preferred alternative for the throat as she heads into a final environmental review, and she agreed – but only for the next few months. She said a consensus, which has eluded state transportation officials for the last five years, needs to be reached this fall on the best approach. If that doesn’t happen, she said, she may just rebuild the existing viaduct and leave the other transportation elements alone if no consensus can be reached on a preferred alternative.

She also narrowed the list of possible options for the throat to three by rejecting out of hand some suggestions advocates have been pushing. For example, she ruled out doing away with one of the Turnpike or Soldiers Field Road lanes to make space for the various pieces of infrastructure. Some advocates have said reducing the number of lanes was possible as more commuters work from home and as a way to encourage more transit ridership.

But Pollack noted the Turnpike handles 150,000 trips a day and Soldiers Field Road 75,000 trips a day, far more than the 18,000 served by the Worcester/Framingham commuter rail line. Even if commuter rail ridership were to double, Pollack said, all the lanes would still be needed.

Pollack also signaled that her latest proposal may be the only viable option because it’s the only one that would not require either temporary or permanent placement of transportation infrastructure in the Charles River.

Pollack said Kathleen Theoharides, the secretary of energy and environmental affairs, who would have to sign off on any environmental review of the project, regards any intrusion into the Charles River as a last resort. “My agencies would consider any intrusion into the river excessive, especially if there are alternatives without any intrusion,” Theoharides said in a statement included in Pollack’s presentation. “The Charles River and surrounding basin is a historic environmental asset to Boston and the surrounding communities, and any impacts should be weighted heavily in the review of the Allston Viaduct replacement project.”

One option that would put all of the transportation elements in the throat area at ground level would take up 244 feet, 40 feet more than is available and requiring the placement of elements of the transportation infrastructure in the Charles River. The other option, nicknamed the hybrid, would elevate Soldiers Field Road above the rest of the transportation infrastructure but require a temporary incursion of Soldiers Field Road into the river during construction. The hybrid proposal also puts the Turnpike below grade.

Pollack said her latest proposal would take 6.5 to 8 years to build, about the same as the all-at-grade option and less than the 8 to 10 years needed for the hybrid option.

She said her latest option is faster to construct because it basically follows the existing footprint, avoids the relocation of some water and sewer infrastructure, and avoids building below grade. She said the proposal allows everything to fit because the proposed viaduct is about 400 feet shorter than the current one, narrower by 8 feet (the Turnpike shoulders are 4 feet rather than 8 feet), and takes up 10,000 fewer square feet.

Pollack did state emphatically that she is now on board with four tracks and three passenger platforms at the proposed West Station. Previously, she had indicated she might go with fewer tracks.

Joe Sullivan, a member of the MassDOT board, praised Pollack for her patience incorporating all the feedback she’s received on the project over the years, but he declared the option of just rebuilding what’s in the throat currently a nonstarter. “This is a forever decision,” he said. “We need to be bold.”

Betsy Taylor, another member of the board, said she was glad Pollack had finally placed a timeline on the endless discussions of what to do with the throat. She said the design of the project needs to be settled and then state officials must shift their focus to figuring out a way to finance the $1 billion project.