Eversource Completes First of Two Undersea Cables to Martha’s Vineyard
Eversource has announced it is nearing completion of a $310 million undersea transmission cable project to serve Martha’s Vineyard.
Eversource has announced it is nearing completion of a $310 million undersea transmission cable project to serve Martha's Vineyard. Two new five-plus-mile cables are being installed between the Island and Falmouth.
Construction began in December 2023. The first cable has already been laid, and installation of the second cable is expected to be completed in the coming weeks, weather permitting. Two new 23-kilovolt cables will land at East Chop and West Chop, replacing aging power infrastructure and enabling onshore connections without diesel backups.
“If we are doing our job right, you should notice nothing,” said Mathew Biron, the director of project management and construction for Eversource. “The impact is really going to be in the avoidance of a reliability issue.”
The project addresses rising energy demand on the Island, driven by more homes adopting electricity as their primary power source.
According to a Vineyard Gazette report, the Island has been receiving power via four undersea cables for decades. During the summer, residents and visitors have benefited from diesel generators.
Eversource advanced its replacement of one of the aging cables, installing a fifth cable after cracks in the infrastructure were discovered in recent years. In 2021, one of the cables failed, resulting in rolling blackouts on the Vineyard.
The Vineyard Gazette noted that a 2024 Martha's Vineyard Commission report recorded a 17% rise in electrical use over the prior decade and projected continued increases as electrification expands.
Construction costs are expected to be shared by Eversource customers across eastern Massachusetts and be reviewed by the Department of Public Utilities as part of a rate distribution process. The costs will be amortized over the project's life to minimize customer impact.
After installation, Eversource will complete onshore connections and conduct integrity testing. Grid connection is anticipated in the first quarter of 2026, with minimal disruption expected for residents if all work proceeds as planned.
