Shetland's tunnels must be connected from day one
Tom Sime is Chief Executive of Exchange Communications, a UK specialist in smart building and cellular connectivity infrastructure. Exchange Communications has delivered key mobile connectivity projects across major locations in the UK, including the Mersey Tunnels, and is currently involved in the development of cellular connectivity infrastructure for the Clyde Tunnel.
“The proposed subsea tunnels linking Shetland’s islands could transform how people live, work and travel. They could provide reliable connectivity between communities, support economic growth and help tackle the long-term challenges created by an ageing and increasingly expensive ferry network.
“But if Scotland is serious about building infrastructure for the next 50 or 100 years, we must ensure we are not designing tomorrow’s tunnels around yesterday’s technology.
“Mobile connectivity must be treated as essential tunnel infrastructure from the outset, not an optional extra to be retrofitted once the concrete is in place.
“That is not simply a question of convenience. It is about safety, resilience and ensuring these tunnels work properly for the people who will depend on them every day.
“The case for fixed links in Shetland is gathering momentum. Shetland Islands Council has identified subsea tunnels as potential alternatives to parts of its ageing ferry network, with the Yell Sound crossing being used as a test case. Recent work by COWI and Stantec has concluded that the tunnels are technically buildable and potentially investable. The proposed Yell tunnel alone is estimated at around £402 million and could take eight years to deliver.
“That is a major infrastructure investment. So the question should be: what does Scotland need these tunnels to do when they open?
“They need to be safe, resilient, digitally connected and capable of supporting technology that will emerge over their lifetime.
“Our recent work on the Mersey Tunnels in Liverpool involved installing a multi-operator 4G Distributed Antenna System across the tunnel network, with more than 7.5 kilometres of cable installed during a six-month programme of tightly constrained engineering windows. The system provides mobile coverage for motorists while also supporting emergency-service communications and public information systems.
“A driver who breaks down, is involved in a collision or sees an incident should not suddenly discover that their mobile phone is useless because they have entered a tunnel.
“Being able to call emergency services, send information or receive instructions can make a real difference. Reliable wireless infrastructure can also support tunnel operators, emergency responders and connected operational systems.
“The UK’s Emergency Services Network also recognises the importance of coverage in critical locations, giving first responders access to voice, video and data communications.
“Connectivity is therefore becoming part of the safety architecture of critical infrastructure.
“Our Mersey Tunnels experience demonstrated this principle, supporting both emergency services and future technologies.
“That is the mindset that should be brought to Shetland.
“And there is another important lesson: retrofitting tunnel connectivity is considerably harder than designing it in from the beginning.
“Anyone who has worked inside a live tunnel understands the logistical challenge: confined environments, restricted access, ventilation, safety requirements, traffic management and limited engineering windows.
“In Liverpool, we worked around a tunnel system carrying around 30 million motorists a year, with limited periods available for installation. It was achievable, but complex.
“Why create that problem in Shetland?
“If we know today that a new subsea tunnel will need communications infrastructure, the logical time to design cable routes, antenna locations, power requirements, equipment spaces and network architecture is before construction begins.
“Not five years later. Not when the first mobile operator asks why there is no signal. And certainly not after the tunnel has opened and engineers are trying to install infrastructure in a live environment.
“The same principle is already being recognised in Glasgow. Exchange Communications is bringing its cellular connectivity expertise to the Clyde Tunnel, alongside wider planned communications and safety upgrades.
“A modern tunnel is no longer simply a hole through rock. It is a connected piece of critical infrastructure.
“That should be reflected in the specification for Shetland from the very beginning.
“The infrastructure should be designed as a multi-operator digital platform, capable of supporting different mobile network operators and future generations of technology.
“That means thinking about 4G and 5G today, but also what comes next, connected vehicles, intelligent traffic management, sensors, environmental monitoring, predictive maintenance and emergency response technologies.
“A tunnel planned today could operate for many decades. We should build its digital foundations alongside the physical ones.
“The whole ambition behind these fixed links is to make island communities less isolated, economically, socially and physically. The Council has highlighted their potential to support population growth, economic development and better access to jobs and services.
“Digital connectivity should be part of that ambition.
“If Scotland is going to invest hundreds of millions of pounds in subsea infrastructure, we have an opportunity to create something genuinely fit for the future, infrastructure that supports not just how people travel today, but how they will live, work, communicate and access services for decades to come.
“That means bringing communications engineers, mobile network specialists and emergency-service users into the conversation from the earliest stages. If the right infrastructure is planned from the outset, it can be integrated more efficiently, delivered more cost-effectively and designed with future technology in mind.
“The Shetland tunnels could become a landmark piece of Scottish infrastructure, not simply because of the physical connection they will create, but because they can demonstrate what a truly modern rural infrastructure project looks like.
“When these tunnels eventually open, they should represent more than a new way of getting from one island to another. They should represent a long-term investment in a better connected Shetland, physically, digitally and economically.”