About 66 miles of electrical transmission lines are proposed to be installed in Long Island, with a majority running throughout Nassau County, in a multi-year, $3.2 billion project to bolster the island’s transmission network and work towards environmental goals.

The Propel New York Energy project is a collaboration between the New York Power Authority, the state’s public power utility, and New York Transco, a New York developer, owner and operator of bulk electrical transmission facilities.

The project includes the implementation of new and upgraded electrical stations along with nearly 90 miles of underground and submarine – or below the sea floor – transmission lines.

The electrical transmission lines will connect the electrical sources to the substations, which then distribute electricity to surrounding homes and businesses through separate distribution lines.

“It’s the backbone of the electric grid,” New York Power Authority senior program director Ana Stachowiak said.

About 58.5 miles of transmission lines will be in Nassau County, along with two new substations. Another 1.6 miles of lines will be installed in Suffolk County.

A majority of the lines will be placed in Long Island, with just 12 miles in New York City and 12.6 miles in Westchester County.

Nearly 10 miles of submarine lines will also be installed, cutting through Hempstead Harbor and the Long Island Sound. Of this, 6.25 miles will be considered part of Long Island.

The transmission lines are planned to be placed under existing public rights of way and utility properties throughout Nassau County and in Suffolk County, Queens, the Bronx and Westchester County.

The project would establish three ties between Long Island and the statewide power grid, mostly utilizing 345kV transmission lines.

Three segments of the transmission lines route will run through North Hempstead on Northern Boulevard, Mineola Avenue to Willis Avenue, and Glen Cove Road.

Of Nassau County, a majority of the lines will run through the Town of North Hempstead and cut through 11 villages. Approximately 19.5 miles of lines will be installed in North Hempstead.

The villages these lines would cut through are Westbury, Old Westbury, East Hills, Roslyn Harbor, Mineola, Williston Park, Roslyn, Flower Hill, Lake Succes, Russell Gardens and Thomaston.

The project intends to bolster reliability, resiliency and redundancy in the electrical grid, while also working towards environmental sustainability goals. This would be achieved through the updated transmission lines which could utilize more clean energy sources.

A majority of the electrical grid downstate is reliant on the use of fossil fuels. The transmission project would bolster the use of renewable energy sources by establishing clean energy pathways that current lines can not sustain.

Construction is anticipated to begin in mid-2026 with about a four-year construction period. Transmission lines are planned to be in service by mid-2030.

While construction is anticipated to take four years, Stachowiak said that does not mean it will be in a single location for the entire duration of the project.

“It’s a long, linear project,” Stachowiak said.

To install the transmission lines underground, a two to three-foot-wide trench would be dug into the selected roadways.

The submarine lines will be installed via a boat with a jet plow used to reach the sea floor and dig below to lay the submarine cables.

For sensitive areas where cables need to be installed, horizontal directional drilling will be used to prevent trench digging.

The project proposal is preliminary and details are still subject to change pending community feedback.

The project is amid its pre-permitting outreach and survey phase which is when they will solicit community and municipality feedback on the project. This is a required component before permits can be applied for.

The application of a state permit to begin the project is anticipated to be filed this summer, but the process is estimated to take place through 2026. It is estimated that the permitting process will take about two years.

The community engagement encompasses garnering feedback and providing education to individuals potentially impacted by the project.

Individuals can provide comments or ask questions by calling the toll-free line 1-800-347-9071 or emailing the developers at info@propelNYEnergy.com. Additional information can be found on its website PropelNYEnergy.com.