COBRAcable HVDC Geophysical, Geotechnical and Cable Crossing Surveys

MMT, Sweden, was contracted by OMM (Offshore Marine Management) to perform geophysical, geotechnical and cable crossing surveys in preparation for the installation of the COBRAcable on behalf of end client TenneT. The project was successfully completed with a four-vessel solution between early September and late November 2014.

The M/V Askholmen performed a shallow water geophysical survey at the landfalls in Eemshaven, The Netherlands, and Fanö, Denmark. The Coastal Chariot from Acta Marine performed a shallow water geotechnical survey utilising MMT’s CPT and Vibro Corer. The M/V Icebeam performed an offshore geophysical survey and geotechnical survey with the Stril Explorer performing cable crossing surveys to establish depth of burial using the Orion Cable Tracking System. The Stril Explorer also undertook the CPT and Vibro Corer works at the end of the project.

The COBRAcable route (approx. 325km) is proposed to be laid across the southern North Sea connecting The Netherlands and Denmark. The COBRAcable is a cross-border project of European significance and is part of the EU Economic Recovery Plan and is designated as a Project of Common Interest (PCI).

The project was a success, with project delivery on time and in budget. It was also the first time MMT and OMM worked together to deliver a project. OMM’s Head office is located in Cambridge, UK. The project was awarded under OMM’s framework agreement held with TenneT for the provision of survey services. OMM nominated MMT as subcontractor for the project, who are well known within TenneT for the provision of Geophysical and Geotechnical survey services. MMT and OMM were both pleased with the contract award and hope for cooperation on future projects.

Image: Seafloor Surface outside landfall in Eemshaven.