Seaway7 completes 95 East Anglia THREE foundations as cable work continues

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Seaway7 has completed installation of all 95 monopile foundations and transition pieces at the East Anglia THREE offshore wind farm, closing a major offshore construction phase as work shifts toward cable installation.

The final foundation was installed by the jack up vessel Seaway Ventus, which carried out the foundation campaign for ScottishPower Renewables. Seaway7 said the scope included some of the largest monopiles installed from a jack up vessel in the European offshore wind sector.

Completion of the foundation campaign clears another major construction milestone for East Anglia THREE, where offshore activity is continuing as the project moves through its next installation phases.

Seaway7’s scope covered the installation of 95 monopiles and their associated transition pieces. These structures form the fixed foundations that will support the project’s offshore wind turbines.

Foundation installation represents one of the most demanding stages of offshore wind construction because vessel operations, heavy lifting, seabed conditions and weather windows all have to align. With 95 foundation sets involved, maintaining a consistent installation sequence is also important for the wider construction schedule.

Seaway Ventus was central to that programme. The purpose built jack up installation vessel is designed for offshore wind foundation work and provides the lifting and elevated working platform required to handle increasingly large components.

The size of the foundations at East Anglia THREE reflects the continuing growth of offshore wind turbines and the corresponding increase in the dimensions and weights of supporting structures.

Seaway7 said the completion was achieved through cooperation between offshore and onshore teams, as well as ScottishPower Renewables and other project partners.

With the foundation scope finished, Seaway7’s work at East Anglia THREE is continuing offshore rather than ending with the departure of the foundation installation campaign.

Cable installation activities are now continuing as part of the company’s remaining delivery scope. The transition illustrates the sequence facing large offshore wind developments, where completion of one heavy marine construction programme opens the way for another specialised offshore operation.

For the project logistics and offshore installation sector, that shift changes the equipment and vessel requirements. Foundation installation centres on monopiles, transition pieces, heavy lifting and jack up operations, while cable work requires a different marine spread and installation process.

East Anglia THREE is part of ScottishPower Renewables’ wider East Anglia offshore wind development off the east coast of England. The installation of the final foundation means all 95 planned turbine positions have now reached this stage of offshore construction.