Could The Shetland Islands Be Connected By Undersea Tunnels?

For archipelago residents, transportation is a vital lifeline, but a reliable way to get from home to work and back is not necessarily a guarantee, particularly if ferry transportation is disrupted by environmental factors.

A commonly cited solution in many cases is an underwater tunnel connecting the islands, one that would not be affected by the weather or ageing infrastructure, that would last for potentially over a century with regular maintenance and would allow the islands to be much more closely connected.

This is why a £402m undersea tunnel connecting the Shetland Islands has been proposed, according to BBC News, with the estimate coming from an engineering consultancy firm and providing the biggest indicator to date of the project coming to fruition.

Given the high costs and the need for vast tunnel boring equipment and conveyor belts to move earth on the island, could a tunnel be the most viable option for securing the future of transportation between the Shetland Islands?

To answer this, it is important to explore the needs of the Shetlands, previous success stories involving underwater transport links, the potential complications of the proposed project and whether the £402m investment is ultimately worth it.

Why Do The Shetland Islands Need Tunnels?

The Shetland Islands are an archipelago consisting of over 100 islands, of which 16 were inhabited, which is roughly 100 miles north of John o’ Groats, the northernmost point of Great Britain.

Embedded deep within the North Sea, the Shetlands have a population of 23,000 people, but travel between the 16 inhabited islands is heavily dependent on an inter-island ferry network operated by the Shetland Islands Council.

These ferry services are heavily weather dependent and frequently prone to disruption, meaning that commuters from the Mainland to the other inhabited islands such as Yell are entirely reliant on the ferry to get from home to work and back.

Any disruption caused by a storm, a strike or the breakdown of a boat can leave someone stranded on another island, causing some employers to set up emergency accommodation for island-hopping employees.

The average age of the ferryboats themselves is over 30 years old, which means that breakdowns are increasingly common whilst parts are harder to source. This means that an issue that has been there since the 1990s has only gotten worse.

Compounding this is capacity; 750,000 passengers use 12 ferries, at a total cost of £23m per year. There is not much of a backup plan if there are any problems, and this unreliability is allegedly stymying the potential of the Shetlands to thrive.

The Shetlands have the most productive onshore windfarm in the UK, where the disruptive stormy winds that make ferries unsafe to cross help to generate more wind-derived electricity than anywhere else in the country.

As well as this, the Shetlands remain a thriving fishing port, which has been the backbone of the archipelago’s identity and economy since time immemorial.

By complete contrast, the island of Unst is home to the only licensed vertical spaceport in the UK, rather fittingly located at one of the northernmost inhabited points of Great Britain.

The Shetlands have considerable potential, but one aspect that has slowed the Islands down is its sensitive transport links, something that has caused people to move away from the northernmost islands in particular. Could this potentially be solved?

Could Underwater Tunnels Help The Shetland Islands?

One of the biggest potential solutions to the problems seen in the Shetlands is to link the islands together using a series of undersea tunnels.

This approach has been used to great success in the Faroe Islands, an archipelago with twice the population of the Shetlands but which has developed one of the most innovative undersea networks of tunnels ever.

The crowning achievement of this was the world’s first underwater roundabout, which helps to link together the 18 islands as part of a network of 23 tunnels, three more of which are also underwater.

The transformation of the Faroe Islands has been dramatic, leading not only to an increase in tourism and productivity but also to an increase in population, supported through a toll system that is better value than the previous ferry network.

This revitalisation has inspired several similar archipelagos to consider the construction of similar tunnels to solve very similar problems for commuters, businesses and tourists alike.

How Would The Proposed Shetland Tunnel Project Work?

This led to a £990,000 consultation on the feasibility of a tunnel project underneath the Shetland Islands, with a specific focus between the Mainland and the second-most populated island of Yell.

Shetland Island Council worked with two engineering consultancy firms, Stantec and COWI, in order to begin to see if a tunnel project was even possible, as well as a rough estimate of costs and an outline of what a potential tunnel project would look like.

The tunnel would be 4.2 miles long and 50m underneath the seabed, allowing it to be immune to the weather conditions that affect the ferries.

It would take eight years in total, including three years of planning and preparatory work and five years of active construction using a similar “drill and blast” process to that used for the Faroe Islands tunnels. Once excavated, a layer of sprayed concrete would provide the structure.

The total cost was estimated to be £402m, of which £327m was how much the tunnel was estimated to cost at current market rate, alongside £25m upfront and a contingency budget of £50m to take into account inflation, delays and other cost stresses.

This amount is significant, which makes funding the biggest factor separating a potentially region-altering project from being made or remaining a pipedream.

The Faroe Islands tunnels were funded through initial borrowing that was repaid through tolls, but alternative funding models include a grant from either the devolved Scottish Government or the central UK Government, private investment, or a public-private partnership.

The Scottish Government has broadly supported the concept, although a lot of work and negotiation will be needed to convert this enthusiasm into a final proposal, let alone a finished tunnel.

However, if the tunnel to Yell is completed and is a success, the concept could be replicated to connect the mainland to Whalsay, Unst and Bressay.