Through the fall of 2015, staff and consultants for ABC worked with MassDOT, their consultants, and members of the I-90 Allston Interchange Task Force to develop alternatives to the original MassDOT design for portions of the interchange and viaduct. ABC’s objective was to lower the grades of the Turnpike so that bridges over the roadway could be lower and grades to the proposed West Station could be reduced. All current options have lower grades. ABC proposed an at-grade alternative that would replace the Turnpike viaduct approaching the interchange on the surface beside the railroad lines and Soldiers Field Road. Another alternative to locate the Turnpike below two railroad tracks on a viaduct was also proposed. Along with the MassDOT Turnpike viaduct option (called 3K-4), all three alternatives will be evaluated in the Draft Environmental Impact Report/Environmental Assessment now being prepared.
The ABC alternative has been evaluated and would be the least cost option to construct, would provide an easier and faster construction sequence, and with the elimination of the highway viaducts, would have the lowest life cycle cost because the highway would be least costly to maintain and viaducts would not need to be reconstructed periodically. Rail operations and access to the planned layover yard and the West Station platforms are easier because all four tracks would be at the same grade at a point east of the station. Issues regarding use of existing open space and construction at the Charles River, however, need to be addressed.
Task Force meetings and individual workshops to discuss design refinements and opportunities for placemaking and future development in the Interchange area are continuing. The date to issue the environmental reports has been extended from June 2016 to a date later in the year to be determined. ABC will continue active participation in this critical project.