SSEN Transmission has marked a major step on its flagship Orkney Link Project with the successful completion of horizontal directional drilling (HDD) at Dounreay, Caithness.

The operation delivered one of the project's most complex engineering activities on the route that will connect Orkney to the national electricity transmission network, supporting the movement of clean, renewable energy to and from the islands.

Engineers drilled and installed an 830-metre underground duct from the Dounreay landfall to a point beneath the seabed offshore. The duct has been designed to allow the future subsea electricity cable to be pulled ashore with minimal disturbance to the coastal environment.

With this milestone, both HDD landfall sections on the route are now in place, following the successful completion last year of similar works of around 1,200m at Warebeth in Orkney.

Environmental specialists worked closely with the project team throughout the programme to help ensure the works were delivered safely while minimising impacts on sensitive marine and terrestrial environments.

-- Advertisement --

The project also deployed innovative construction techniques, including remotely operated excavators to undertake the final subsea section of drilling. This enhanced safety for marine construction teams while demonstrating the innovative engineering being applied to deliver major electricity infrastructure.

Ian Clark, Project Director for the Orkney Link Project at SSEN Transmission, said: "The completion of horizontal directional drilling at Dounreay represents a huge milestone for the Orkney Link Project and is a testament to the expertise, collaboration and innovation demonstrated by everyone involved.

"This was one of the most complex construction activities on the project and required careful planning to ensure it could be delivered safely while protecting the surrounding environment.

"With both landfall HDD sections now complete, we're another significant step closer to connecting Orkney to the national electricity transmission network, unlocking renewable energy potential and supporting our transition to a cleaner, more secure energy system for our customers in Orkney."

The works were delivered by Principal Contractor RJ McLeod, supported by specialist subcontractors OCU Group, Lucion, Kirkwall-based Leask Marine, and HDD specialists Peter McCormack & Sons.

The Orkney Link Project forms part of SSEN Transmission's programme of investment to reinforce the electricity transmission system across the north of Scotland and enable the connection of renewable generation needed to support Scotland's and the UK's net zero ambitions.