Delaware Memorial Bridge twins will soon have an additional layer of vessel collisions, such as the one that caused last year’s collapse of the Key Francis Scott bridge in Baltimore.
Scheduled for completion in September, the two -year -old dollars project adds a total of eight “dolphin” cylinders 80 feet in diameter next to the 440 -foot towers 440 feet 440 feet in length. Built by Re Pierson Construction Co., PillarsGrove Township, NJ, cells are at least 443 feet from the edge of the Delaware Delaware Navigation Channel 800 feet.
For more than 50 years, the only protection of Delaware Memorial Bridge Towers of the ship strikes has been a successful channel defense system that successfully absorbed the impact of a oil truck in a year after the second extension to bring the I-295 between Pennsylvania and New Jersey in 1968. Jim Salmon, a spokesman for Delaware River and Bay. (DRBA) says that the agency has acknowledged a long time for the need for the need for the need for the need for the need for the need for the necessary (DRBA) (DRBA).
“Today’s loading ships are larger, faster and more products than those passing the river in the 1960’s,” says Salmon. “The old defense system was outdated and it had to be improved.”
Partially funded by a federal grant of $ 22.25 million, the construction of the dolphins began in July 2023. Each structure consists of 150 piles of sheet metal of 115 feet in length driven 45 feet on the riverbed, which extend through clay clay to a underlying layer of dense sand. The cells are filled with sand, stone and riprap. A concrete ring is built around the outer face of each cell. An updated defense system is also part of the project, which has been closely coordinated with the United States Coast Guard, allowing the project to progress with a minimum impact on traffic shipping traffic
Salmon says the new system is designed to withstand the impact of a 120,000 demolished neopanamax ship traveling to approximately 7 knots.
In comparison, the key bridge was struck by M/V Dali, also a Neopanamax container boat with an estimated tonnage of 116,000 at the time of the collision. In a report of March 18, 2025, which provides an evaluation orientation of vulnerability for Ponts owners, the National Transport Safety Board (NTSB) said that the four 28 -foot dolphins in diameter, throughout the key bridge navigation channel, were insufficient in size and location to protect the piles of a collision structure. The investigation of the Incident Agency is in progress.
Although the construction of the Delaware’s Bridge Memorial collision system was underway when the key bridge was hit, Salmon says that the incident has increased attention to the project.
“Some owners colleagues have requested information or plans and visited the construction site for more information on what we have done,” he says.
