JCP&L completes work on new transmission line out to NJ barrier islands

Published on August 06, 2021 by Dave Kovaleski

© JCP&L/FirstEnergy Corp.

Jersey Central Power and Light (JCP&L) has completed work on replacing an underwater high-voltage transmission line across Barnegat Bay along the Tunney-Mathis Bridges.

The new 34.5-kilovolt line transmission line will enhance electric service reliability to New Jersey’s barrier islands. The old lines were believed to have been damaged by dredging operations in recent years. It is one of four high-voltage power sources serving approximately 30,000 JCP&L customers on the barrier islands, including the communities of Point Pleasant Beach, Bay Head, Mantoloking, Normandy Beach, Brick, Lavallette, Dover/Toms River, Ortley Beach, Seaside Heights, Seaside Park, Berkeley and Island Beach State Park.

“This project supports our commitment to using new, innovative ways to improve service reliability by utilizing an emerging technology that placed the submarine line in a safer location while also minimizing the work’s impact on the bay’s fragile ecosystem,” Jim Fakult, president of JCP&L, a subsidiary of First Energy, said. “The new line helps ensure that our barrier island customers will have the reliable service they need in these peak summer months.”

The new line sits 10 feet below the bay’s sandy base. To bury the line, JCP&L brought in a special underwater trenching sled. It was the first time the technology was used by any FirstEnergy company. The sled used water jets at 150 pounds-per-square-inch pressure to blast a trench about one foot wide and 10 feet deep for the new power cables. Each of the three cables that make up the line is wrapped with 28 strands of aluminum armor wire, eliminating the need for a bundled armor casing commonly used in underwater power line projects.

A large barge was used to pull the 12-ton, school bus-sized sled at rates up to 10 feet per minute. As the sled was pulled along the bottom of the bay, the trench collapsed behind it, leaving only a shallow depression marking the location of the line. The 5,800-foot crossing was completed in just a few days.

JCP&L serves 1.1 million customers in the counties of Burlington, Essex, Hunterdon, Mercer, Middlesex, Monmouth, Morris, Ocean, Passaic, Somerset, Sussex, Union, and Warren.