DeepOcean winding down North Sea FPSO disconnection gig for TotalEnergies

November 25, 2025, by Melisa Cavcic

Norwegian ocean services provider DeepOcean is close to crossing the finish line for an assignment in the North Sea, which entails the disconnection and tow of a floating production, storage, and offloading (FPSO) vessel, alongside the disposal of associated subsea infrastructure on the UK Continental Shelf (UKCS).

While revealing that it is nearing completion of a contract awarded by TotalEnergies for the disconnection and tow of the FPSO Gryphon Alpha and the removal of associated subsea infrastructure, DeepOcean highlights that this marks a first, with proprietary tooling designed and developed in-house, enabling the entire scope to be executed fully diverless.

Robin Mawhinney, Managing Director of DeepOcean UK, commented: “This project is a standout achievement for DeepOcean. We have a world-leading track record in finding unique ways to execute complex subsea operations using our in-house design, technology and tooling expertise.

“The bespoke tooling created for this scope of work allowed us to perform the entirety of the scope using diverless methodologies that produced exemplary outcomes. Everyone involved in the design, build and offshore operations should be extremely proud of what they have achieved.”

The company’s scope of work entailed flushing of subsea pipelines and manifolds, disconnecting flowlines and umbilicals from trees, removing risers and midwater arches, and recovering FPSO moorings.

Following the unit’s disconnection, the firm also managed the towing of the FPSO. According to DeepOcean, the spool disconnection and blind flange installation represent pioneering achievements in diverless operations.

The project has been delivered by the firm’s team in Aberdeen, UK, with support from the office in Haugesund, Norway, as required.

The project is close to being finished with the recovery of mooring chains and removal of the risers and mid-water arches to be carried out before year-end. Gryphon Alpha was the North Sea’s first purpose-built, permanently moored FPSO, originally commissioned by operator Kerr McGee.

DeepOcean explains that the asset was later acquired by Maersk Oil and then by TotalEnergies through its 2018 merger. While the field was initially expected to have a lifespan of just ten years, it has exceeded expectations, producing more than 250 million barrels of oil equivalent over three decades of operation.

“As DeepOcean prepares to complete the final phase of this decommissioning project, we remain highly committed to delivering safe, efficient and reliable operations that will reinforce a very proud legacy for Gryphon Alpha and everyone who has supported her over the years,” emphasized Mawhinney.

DeepOcean has been a busy bee this year, securing multiple new contracts and extensions, as illustrated by a subsea tie-back deal for another hydrocarbon field development in the UK.