When Pike work goes off, highway to come down

A stretch of the Massachusetts Turnpike in Allston will be rebuilt at ground level when the state demolishes the Interstate 90 viaduct at the western entrance to Boston, under a final design decision made Thursday by Transportation Secretary Stephanie Pollack.

The “hybrid” design also calls for a section of travel lanes on Soldiers Field Road to be built along a new viaduct to accommodate future pedestrian and bicycle lanes.

“We were trying to balance a lot of different factors and considerations and the choice to move the interstate at grade and elevate Soldiers Field Road really gave us the best balance between a road that would work as a road and protect the Charles River and give access to the neighborhoods,”

Pollack said. Pollack published the decision on Thursday, ending a long-boiling debate over whether the Allston viaduct on the turnpike, which needs replacing, should be rebuilt or abandoned in favor of a highway at ground level that neighborhood activists supported as a way to open parts of Boston and Cambridge to future development.

The new viaduct at the “throat” of Soldiers Field Road, according to MassDOT, will allow the state to keep infrastructure farther away from the Charles River and create more park space and room to separate pedestrians and bicyclists on the Paul Dudley White Path.

The hybrid option also preserves the potential for future public transit service to run through the throat area of the project between Allston and Cambridge using the Grand Junction Railroad.

Cost was not a factor in the decision, Pollack said, because all of the design options fell within the range of $1 billion to $1.1 billion.

The straightening of the Turnpike in Allston is expected to unlock acres of land owned by Harvard University for development.

MassDOT, the MBTA and Boston University also own property in the area. The full project will take approximately eight years to construct.