Onshore and offshore surveys have been vital to the development of Sofia since early environmental impact assessment work that informed the original development consent application. As the project moves through its construction phase, surveys will continue to remain an integral part of our activity.
A total of twelve ornithology aerial-LiDAR surveys to collect data on kittiwake flight height and abundance have now been completed which marks the end of our pre-construction ornithology surveys.
Investigations into potential UXO and archaeology features in the nearshore area and along the export cable corridor and at the array site were completed in summer 2022. An ROV investigated potential UXOs and several possible archaeological features and also inspected an additional aid to navigation buoy location. Also in summer a multi-beam seafloor survey was carried out in advance of the main offshore landfall horizontal directional drilling (HDD) works, underway in late 2022 and continuing into 2023. Multibeam and sidescan sonar surveys of the pre-plough array cable routes and foundation locations were undertaken in early 2023 in advance of scour protection installation.
The onshore cable route surveys were completed earlier in 2022 in readiness for the start of construction of the civil engineering works on the onshore cable corridor, now in full swing. The surveys included a team of onshore archaeologists from Durham University’s Archaeological Services (DUAS) carrying out excavation and recording work at locations along the cable route, from landfall near the coast to the Wilton onshore converter station site.
Following magnetometer surveys earlier in 2022, some manual excavations were carried out on the beach and within the intertidal zone to review potential UXOs identified in that area. As with the multi-beam seafloor survey above, activity was completed ahead of the start of the HDD at the landfall. The HDD work will install ducts for the offshore export cables to be pulled through in 2023.