Great Lakes Dredge & Dock Corporation announced the launch of its vessel Acadia at Hanwha Philly Shipyard.
The Acadia is the first U.S.‑flagged, Jones Act‑compliant subsea rock installation vessel.
It is designed to transport and install up to 20,000 metric tons of rock on the seabed.
This rock provides scour protection for subsea infrastructure such as power and telecommunications cables, oil and gas pipelines, subsea structures and offshore wind turbine foundations, helping to prevent erosion from waves, currents or mechanical impacts.
Construction of the Acadia used steel sourced from Ohio and labour from New Jersey, Pennsylvania, Texas and Louisiana, generating over one million man‑hours of high‑paying employment at the shipyard.
Once operational, the vessel will employ U.S. mariners for many years. In addition to serving the U.S. market, Great Lakes plans to deploy the Acadia in international offshore energy markets.
The vessel faced schedule delays and legal disputes with Hanwha Philly Shipyard; Great Lakes initially filed and later withdrew a court complaint, opting for private resolution following the yard’s acquisition by Hanwha Ocean in December 2024.
Despite challenges in the U.S. offshore wind sector, including contract cancellations and regulatory rulings affecting Jones Act interpretations, Great Lakes secured multiple contracts for Acadia, including Empire Wind I and Sunrise Wind, plus a third unnamed project, extending work into 2026.
Great Lakes Dredge & Dock Corporation is a publicly traded U.S. dredging and marine construction company listed on NASDAQ. With over 135 years of operations, it owns and operates approximately 200 specialized vessels. It offers dredging, subsea rock installation, port deepening, shoreline protection and international marine projects.
Hanwha Philly Shipyard is a U.S. shipbuilding facility in Philadelphia, now part of South Korea’s Hanwha Ocean since December 2024. It constructs vessels under the Jones Act for the U.S. market, and experienced legal disagreement with Great Lakes regarding project timelines for the Acadia.
Ulstein Design & Solutions B.V. is a Netherlands‑based naval architecture and engineering firm.