Simultaneous Subsea Inspection & 3D Scanning Performed at Sangomar Field

DeepOcean and Woodside Energy have successfully performed simultaneous inspection and 3D scanning of 69 subsea structures at the Sangomar field offshore Senegal.

The operation used a new methodology and specialized technologies to complete a full-field baseline subsea survey alongside a full 3D scan at scale without the need for additional offshore personnel. This dual-scope approach marks a shift from traditional subsea routines, which have historically required two separate Remotely Operated Vehicle (ROV) operations.

Øyvind Mikaelsen, CEO of DeepOcean, commented, “Completing an inspection routine and 3D scanning of subsea infrastructure have historically been performed in two separate ROV operations. However, we have developed a remotely supported holistic system that allows us to conduct both operations simultaneously – enabling us to cut vessel days and costs for the operator. We are really pleased that Woodside wanted to trial the solution and of course the successful result.”

The solution combines inspection engineers, ROV pilots, and ROVs equipped with specialised scanning hardware. It includes data processing software enabling the use of Computer-Aided Drawings (CAD), ROV footage, and sonar, as well as digital twin capabilities and proprietary subsea 3D imaging software for generating accurate 3D models.

Mikaelsen added, “We have over the past decade built up an internal ecosystem that enables us to achieve the desired savings in time, vessel days and costs. This isn’t just about software or hardware, but how our service is integrated with the overall subsea inspection offering and the wider business. And by applying 3D reconstructions in our operations, we improve our capacity to detect structural anomalies like cracks or deformities and understand their proximity to critical components within our clients’ subsea assets, enabling timely maintenance and preventing failures.”

During the campaign at the Sangomar Phase 1 Development, which included the scanning of 17 subsea trees, the team captured high-resolution data to support detailed planning and future maintenance activities. The Sangomar deepwater oil field is located 100 kilometers south of Dakar and commenced production in June 2024. DeepOcean, which operates several sites across West Africa, executed the scope from the offshore subsea construction vessel Island Ocean.

Robin Mawhinney, Executive Vice President for DeepOcean’s EMEA region, stated, “We completed the simultaneous operation at slightly above half the time it would traditionally take to perform two separate operations, while doubling the data output for Woodside. We believe performing the simultaneous operation at scale without deployment of additional personnel on board was an industry first, but the most important thing is that we have successfully proven that there are substantial time and cost savings associated with this approach.”

The project falls under a wider agreement established in June 2024 for DeepOcean to provide subsea Inspection, Maintenance, and Repair (IMR) services for the field, including project management, engineering, and underwater inspection of the FPSO.

Ben Witton, Sangomar Subsea Lead at Woodside, said, “We are constantly looking for solutions that enhance the efficiency and quality of our subsea operations. DeepOcean’s dual-scope approach has delivered meaningful gains by reducing offshore time while providing richer data across the Sangomar field. This kind of innovation supports safer, more informed decision-making for future inspection and maintenance activities, and we’re pleased to see the benefits realised at scale.”