National Grid is preparing to begin construction on the D-156 Refurbishment Project, a major infrastructure improvement that will upgrade approximately 5.5 miles of overhead 115 kilovolt (kV) transmission line within an existing utility right-of-way.

The project area extends through Southborough, running from National Grid’s substation on Northborough Road to a point south of Nichols Street. This work is a key investment to replace aging infrastructure, improve system reliability, and strengthen the region’s electrical transmission network.

As part of this effort, crews will replace 37 existing wood structures and 5 steel structures with new, engineered light-duty weathered steel structures. In certain cases, structures may be slightly relocated or increased in height to meet modern engineering standards and ensure compliance with environmental protections.