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.
The first eight ornithology aerial-LiDAR surveys to collect data on kittiwake flight height and abundance were completed in 2021/2022 with the four remaining surveys to be flown before the end of August this year. This will be the second and final year of our pre-construction ornithology surveys.
In 2021, the first phase of investigations of potential UXO and archaeology features was undertaken in the nearshore area. In late June 2022, the second phase of the UXO and archaeology campaign will get underway along the remainder of the export cable corridor and at the array site. An ROV will investigate potential UXOs, and several possible archaeological features and will inspect an additional aid to navigation buoy location.
Also in June a multi-beam seafloor survey will be carried out in advance of the main offshore landfall horizontal directional drilling (HDD) works planned for this summer.
The onshore cable route surveys were completed earlier this year 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 will be 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 will be completed ahead of the start of the HDD at the landfall in summer. The HDD work will install ducts for the offshore export cables to be pulled through in 2023.