Shetland islands plan undersea tunnels to replace ferries

Shetland Islands Council backed a draft strategy for undersea tunnels that would link Mainland to Yell and Yell to Unst, with two further tunnels potentially connecting Whalsay and Bressay. The plan, set against an indicative opening year of 2034, carries a total estimated cost of about £1.5 billion for the four crossings.

The ferry network is the islands’ social and economic backbone. Shetland’s inter-island service runs 12 vessels, makes about 70,000 sailings a year to nine islands and carries roughly 750,000 passengers. Council documents put operating costs at £25 million for 2024/25, while the average vessel age has reached 32.5 years.

The council commissioned its Inter-Island Transport Connectivity Programme in 2024 after reports flagged rising costs, an ageing fleet, crew recruitment and retention problems and limited vehicle-deck capacity. A fixed-link model study by Stantec and COWI, using Yell Sound as a test tunnel, found that the tunnel is buildable and investable. That study put the Mainland-to-Yell section at £402 million and said it would take eight years to complete.

Council leader Emma Macdonald said: “When islands have fixed links like causeways, bridges and tunnels, they experience repopulation, economic growth and a reduction in average age.” She added: “Doing nothing is not an option in Shetland.” COWI executive vice president Andy Sloan said the engineering challenge is relatively straightforward and argued that fixed links could help reverse depopulation, support services and economic growth.

The Faroe Islands have built 23 road tunnels since the 1960s, while Norway has more than 900 tunnels. Fixed-link investment there has been underpinned by substantial central-government support and, in the Faroes, helped create one of the world’s highest-income economies and reverse population decline. Councillor Moraig Lyall, who chairs the council’s environment and transport committee, said talks with the UK and Scottish governments were continuing.