The New Hampshire Seacoast region grew substantially over the last decade, straining the existing transmission system and leading to the need for additional transmission capacity. Critical customers in this area include precision manufacturers, pharmaceutical companies, investment firms, universities and a large residential population.
To prevent outages and support the increased demand, the Independent System Operator of New England (ISO-NE) selected a suite of projects, including the complex Seacoast Reliability project, to modernize the system in the region. Overseen by Eversource’s engineers and project managers, the Seacoast’s 13-mile (21-km) long, 115-kV transmission line was energized on May 29, 2020, after thorough planning and execution. The final route traveled along a rail line, across a college campus, through residential neighborhoods and historic sites, and beneath an environmentally sensitive tidal bay.
Following are images from the project. For a more in-depth analysis of the project, see the April 2022 issue of T&D World magazine.