Sonar investigations have been commissioned for the proposed subsea tunnels for Shetland.
The move is a major milestone for plans to build tunnels between the Shetland mainland and Yell, and Yell and Unst. The report will make recommendations for the seismic survey locations that will contribute to the determination of the tunnel alignments.
Site visits will begin at the end of March and fieldwork is expected to take up to three months. The report will be published within six weeks of completion.
The Unst and Yell Tunnel Action Groups (UTAG & YTAG), which have spearheaded efforts to advance the tunnel project, raised the funds to commission the investigative work. Norwegian consultancy Norconsult has been engaged to carry out the project, thanks to financial contributions from local businesses, individuals, and community supporters who have backed the initiative.
Norconsult has undertaken similar projects in Scandinavia and the Faroe Islands.
“We are delighted to have been able to engage such highly experienced industry experts. Norconsult will bring the skills and experience that they have gained from their work in areas where tunnelling is well established to our project and indeed the UK,” said Duncan Gray, joint chair of Unst Tunnel Action Group.
Graham Hughson, joint chair of Yell Tunnel Action Group, said it was a “huge step forward” for the project.
“Norconsult’s role will be to prepare the basis for carrying out seismic ground investigations using sonar technology, provide a follow-up and report on the seismic investigations, prepare the tunnel alignments (choosing the most probable alignments using updated grade requirements), and prepare overviews and longitudinal sections for the tunnels. Should adjustments be needed following the seismic investigations, Norconsult will refine the alignments accordingly,” said Hughson.
The seismic surveys, which will be commissioned separately, are expected to be completed in 2026. The seismic investigations will be carried out by the Norwegian company GeoPhysix, as a sub-consultant to Norconsult.
“We are absolutely delighted to have reached this breakthrough stage in the project’s development, and to finally be laying the groundwork to make things happen,” said Alice Mathewson, joint chair of Unst Tunnel Action Group. “It is thanks to the many businesses and private individuals in our communities and beyond who have donated to the Groups that we have been able to reach this milestone moment. It is the donators’ vision and generosity that has enabled us to move forward so significantly from planning to real action. We are incredibly grateful for every contribution.”
Tunnels are being considered in Shetland Islands Council’s ongoing review[https://www.tunnelsandtunnelling.com/news/shetland-islands-council-explores-tunnel-potential/] of its inter-island transport network and public engagement is under way.
