Eversource: 550-foot-long pipe to house new 115-kV line installed in Massachusetts

Eversource spokesperson Reid Lamberty on Dec. 12 told TransmissionHub that the total estimated cost of the Mystic to Woburn project is $138.8m

Eversource Energy on Dec. 9 said that it recently installed a 550-foot-long pipe that will house the new 115-kV Mystic to Woburn Line Project, which is designed to enhance reliability for the overall electric system and address the growing need for electricity in the region, as identified by ISO New England (ISO-NE).

The underground line will connect company’s Mystic substation in Everett and the Woburn substation, Eversource said, adding that the line will extend about eight miles between the two substations, passing through Everett, Boston (Charlestown), Somerville, Medford, Winchester, and Woburn.

As noted on the project’s webpage, the project’s estimated in-service date is in 2020.

Eversource spokesperson Reid Lamberty on Dec. 12 told TransmissionHub that the project’s total estimated cost is $138.8m.

According to Eversource’s website, work also continues on the approximately five-mile, 115-kV Mystic-East Eagle-Chelsea Reliability Project, which involves installing a new substation in the East Eagle neighborhood of East Boston, Mass., as well as two new, underground transmission lines to connect the new substation to existing substations in Everett and Chelsea.

According to that project’s webpage, the East Eagle-Mystic line will be built under the streets in Chelsea and Everett and connect to an existing duct bank connecting Chelsea and East Boston, while the East Eagle-Chelsea transmission line will be located within an existing duct bank and manhole system in East Boston and Chelsea.

Construction on the lines began in 2Q18 and the projected in-service date for the line portion of the project is in 1Q20.

Lamberty said that the total estimated cost of the transmission line portion from Mystic to Chelsea is $56.7m.

Eversource’s website also noted that construction is expected to begin this month in Everett, Malden, and Melrose in Massachusetts on the 345-kV Mystic to Golden Hills Reliability Improvement Project, which spans 6.1 miles from the Mystic substation through Malden and Melrose to National Grid’s Golden Hills substation in Saugus — construction in Saugus is expected to begin in 1Q20.

Work on that project includes replacing two aging, underground cables with newer technology cable, the project’s webpage noted.

The projected in-service date for that project is in 3Q21, according to the site.

Lamberty said that the total estimated cost of the project is $72.4m.

Another project in the area estimated to be in service in mid-2021 is the approximately 8.5-mile, 345-kV, underground Woburn to Wakefield Line Project that will connect the Woburn substation and National Grid’s Wakefield Junction substation in Wakefield, Mass., according to that project’s webpage.

The project would pass through the towns of Woburn, Winchester, Stoneham, and Wakefield, the site noted.

Lamberty said that the total estimated cost of the project is $201.2m.

According to a document on National Grid’s website, the project addresses potential overloads on existing transmission lines first identified in ISO-NE’s 2008 Needs Assessment, reevaluated in 2013/2014, and confirmed in ISO-NE’s 2015 Needs Assessment.

Article amended at 6:50 p.m., EST, on Dec. 12, 2019, to include comments from the Eversource spokesperson.