The survey is intended to provide additional geophysical data to ensure the seabed is clear of obstructions, such as unexploded ordnance from the Second World War, prior to construction.
Under the contract, Fugro EMU will use three vessels for the survey work, which is scheduled to commence this month.
In particular, the 41m Fugro Helmert vessel will survey at the main wind farm site while the 24 RV Discovery will operate on both wind farm site and export cable route. The 12m Fugro Valkyrie will survey the near shore works on export cable route.
Fugro EMU deputy geophysics business line manager Nick Simmons said: "We are looking forward to applying our specialist skills and resources in UXO detection at this significant site and are pleased that our extensive experience continues to contribute to the strong relationship between Fugro and DONG Energy."
Dong plans to select another contractor at a later stage to carry out a detailed survey using a remotely operated vehicle to check and deal with potential debris or ordnance.
Dong Energy Walney Extension program director Andrew Cotterell said: "Carrying out geophysical surveys is an important step before we can safely begin offshore construction.
"We are delighted to be working with an experienced UK contractor on this phase of our program."
Located next to the 367MW Walney offshore wind farm, the Walney Extension farm is planned to be developed in two phases, each with a capacity of 330MW.
Upon completion, the project is estimated to generate enough electricity to power over half a million homes.
Image: Fugro Helmert survey vessel at sea. Photo: courtesy of DONG Energy.
