Steel cutting for Subsea Rock Installation Vessel at Philly


On 20 July 2023, U.S. President Joe Biden attended the steel-cutting ceremony of the subsea rock installation (SRI) vessel 'Acadia', under construction at Philly Shipyard. Designed by Ulstein Design & Solutions B.V., this will be the first of its kind U.S.-built vessel.

Great Lakes Dredge & Dock (GLDD) rock installation vessel for the US offshore wind industry.
Great Lakes Dredge & Dock (GLDD) rock installation vessel for the US offshore wind industry.

Offshore wind will play a crucial role in helping the U.S. meet its decarbonisation goals, and Philly Shipyard is a part of it by constructing the SRI vessel. Owned by Great Lakes Dredge & Dock Company (GLDD), the 'Acadia' will be critical in building the future of the U.S. offshore wind energy industry, including establishing a U.S.-based rock supply chain network and help reach the Biden administration’s ambitious goal of 30 GW of offshore wind generation by 2030, which is estimated to service more than 10 million American homes.

The vessel will be installing protective layers of rock at offshore wind turbine foundations by means of an inclined fall pipe system. Furthermore, its large and strong aft deck area makes the vessel a highly flexible asset to GLDD, enabling specialised subsea operations.

The SRI vessel is designed to carry up to 20,000 MT of rock and will transport and strategically deposit these rocks to the ocean bottom, laying a foundation for the monopiles, which serve as the prevailing support structure for offshore wind turbines. The ship will have an overall length of 140.5 metres, a breadth of 34.1 metres, and crew accommodations for 45 people.

Please contact us for more information

Edwin van Leeuwen Ulstein 19 comp bw
Edwin van Leeuwen

Managing director

Tel: +31 653144777

Ulstein Design & Solutions B.V.

Cornerstone Building (6th floor)
Rotterdam Airportplein 32
3045 AP Rotterdam
The Netherlands

Tel: +31 10 475 00 11