Great Lakes Launches First US Subsea Rock Installation Vessel
July 24, 2025
Great Lakes Dredge & Dock Corporation, the largest provider of dredging services in the United States, has launched the first U.S. flagged, Jones Act-compliant subsea rock installation (SRI) vessel, named Acadia, at Hanwha Philly Shipyard.
The Acadia vessel is engineered to transport and precisely install up to 20,000 metric tons of rock on the seabed.
The rock provides critical scour protection for subsea infrastructure including subsea cables for power transmission, telecommunications cables, oil and gas pipelines and subsea structures and offshore wind turbine foundations, preventing erosion caused by waves and currents and mechanical impacts from equipment and vessels.
The delivery of the vessel is expected early in 2026.
With steel sourced from Ohio, and labor from New Jersey, Pennsylvania, Texas, and Louisiana, construction of the Acadia created more than one million manhours of high paying jobs at the shipyard and once operational will employ U.S. mariners for many years to come.
In addition to supporting the U.S. domestic market, Great Lakes has expanded its market focus for the Acadia to work in the international offshore energy development markets.
“We are excited to see the launch of the Acadia, getting us closer to her expected delivery early next year which will also mark the completion of our major new build program. The Acadia is the centerpiece of our offshore energy growth strategy and will begin operations immediately upon leaving the shipyard,” said Lasse Petterson, President and Chief Executive Office at Great Lakes.
“The launch of the Acadia marks a major milestone for our Offshore Energy business. Upon delivery, the Acadia will start her journey towards New York for the installation of rock for the Empire Wind I offshore wind farm and continue working on the U.S. East Coast on contracted work through the end of 2026.
“Over the last two years we have actively engaged with clients for new engagements on offshore energy projects for Acadia for 2027 and beyond,” added Eleni Beyko, Senior Vice President, Offshore Energy at Great Lakes.
