Inch Cape Offshore Windfarm – Landfall Civils Works

The project involved the installation of two 675mm diameter stainless steel ducts through the existing sea defence wall, to accommodate the connection of the export cables from the Inch Cape offshore windfarm into newly constructed transition joint bays and on to their new substation located in the Cockenzie site.

To enable this, a secant piled cofferdam was constructed behind the existing wall, providing a dry working area and structural support during the controlled demolition and reinstatement phases.

Key elements of the works included:

• Construction of a secant pile cofferdam to the rear of the sea wall.
• Careful demolition of the existing sea defence wall to allow duct installation.
• Installation of stainless steel ducts from the Lowest Astronomical Tide (LAT) mark into the Cockenzie site.
• Reinstatement of the sea wall using bespoke precast concrete panels and sheet pile toe protection.
• Proof dig operations extending 500m offshore from LAT, using a backhoe dredger to confirm seabed conditions ahead of cable installation.
• Terrestrial works including construction of cable winch foundations and jointing bays to the rear of the secant pile cofferdam.
• Grouting of the ducts post-installation and supervision of the cable installation works.

The project began with a six-month Early Contractor Involvement (ECI) phase, during which we collaborated closely with the ICOL team and their civil designers to develop the temporary and permanent works designs, agree a fixed NEC4 Option A contract price, and secure all necessary consents and licences from stakeholders including East Lothian Council, Forth Ports, SEPA, Marine Scotland, Crown Estates, Siemens, and Balfour Beatty.

Following the successful completion of the ECI phase, Charles Brand was awarded the main contract and formally appointed as Principal Contractor.