Multiple vessels set to swarm Dogger Bank A & B area for subsea ops

Several subsea operations are scheduled to soon commence at the sites of the first two phases of the Dogger Bank Wind Farm, currently under construction off the North East coast of England.

OSV Isle of Jura; Photo source: Seafast Maritime

Later this month, NKT will begin nearshore intervention works in support of the installation of the Dogger Bank B export cable in the Dogger Bank A & B Export Cable Corridor, with the offshore service vessel (OSV) Isle of Jura to be moored at the site.

Starting on or around 25 March, diving operations will be carried out from Isle of Jura, including exposing the HDD exit points and preparing the HDDs for the subsea power cables. Once the cables have been installed, the diving activities will include sealing and grouting of the ducts.

The crew transfer vessel (CTV) Seafast Don will be carrying out MBES surveys of the seabed and along the pre-cut trenches throughout the dredging activities and the dredger barge Abeko Server 3 will be carrying out spoil management, trenching and backfilling activities. The latter will commence once a subsea cable has been installed.

Starting on or around 1 April, the vessel Sima will be conducting Pre-Lay Grapnel Run (PLGR) operations along the Dogger Bank B export cable corridor in the Southern North Sea.

The Pre-Lay Grapnel Run campaign in the Dogger Bank A inter-array cable area will continue this month, with the anchor handling tug (AHT) BB OCEAN set to be deployed for these operations.

At the end of this month, Subacoustech Environmental is also scheduled to begin performing underwater noise monitoring during the piling operations for the jacket foundation of the offshore substation. Underwater noise monitoring sensors will be deployed from VOS Start within the Dogger Bank A and B construction areas. 

Meanwhile, the UXO work at the Dogger Bank A and B wind turbine array sites will also continue.

Last year, the UXO inspection operations identified the presence of several confirmed UXO items and the clearance work was scheduled for this year.

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The items identified in the Dogger Bank B array construction array have been removed during a recent clearance campaign while the Dogger Bank A array construction area will be cleared in a separate campaign.

The 3.6 GW Dogger Bank Wind Farm is being built in three 1.2 GW phases some 130 kilometres off the UK coast.

The project, owned by a joint venture between SSE Renewables (40 per cent), Equinor (40 per cent), and Vårgrønn (20 per cent), will be the world’s largest offshore wind farm once completed, providing enough electricity to power roughly six million UK homes a year.

Offshore construction started last year with the first monopile foundations installed in July 2022.

The 3.6 GW offshore wind project will consist of 277 offshore wind turbines.

Phases A and B will feature a total of 190 Haliade-X 13 MW turbines and phase C will comprise 87 Haliade-X 14 MW turbines.

The developers are now also looking into building what would be the fourth part of Dogger Bank Wind Farm, Dogger Bank D.

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