In an increasingly uncertain world, the UK must safeguard its critical underwater infrastructure

It is no surprise there is a great deal of scrutiny on what happens in and around our waters and why, in a world that seems increasingly unstable, safeguarding these assets is a matter of national importance. By its very nature, the sea is unpredictable; we must be cognisant and alive to what might happen, be it within or outwith our control, and either accidentally or maliciously.

A recent report from the Joint Committee on the National Security Strategy highlighted the vulnerability of subsea cables and the potential for them to become a target. By extension the same can be said for the power cables that allow power generated by offshore wind turbines to be used in homes up and down the country.

The backbone of modern life

Whether you live five or 50 miles from the coast, subsea cables play a vital role in everyday life. Almost all (95 per cent) of the world’s data traffic, from multi-billion-dollar financial deals to the latest WhatsApp group chat meme, is transmitted through subsea data cables. Often these stretch tens of thousands of kilometres and occasionally they are little bigger than the diameter of a hosepipe.

The UK serves as a global crossroads for internet traffic, with its data links to the outside world carried almost entirely by subsea cables. Increasingly, a handful of high-capacity routes, driven by the demands of major technology companies, are expected to handle most of this traffic. The Joint Committee warns that this concentration is creating a small number of high-value targets.

Particular vulnerabilities exist around the UK’s outlying islands, military communications and the financial sector. While sabotage of individual links may not cripple the nation, it would still be “costly, provocative and difficult to prevent.”

More extensive attacks, however, could trigger catastrophic disruption - shutting down payment systems, fracturing supply chains, degrading communications, straining emergency responses, and unleashing cascading failures as vital online authentication services break down.

Power cables are larger, but even then - despite layers of armouring, protection and the added security of seabed burial – they are relatively exposed.

A suitable cable strategy should take two forms once installed. Continuous monitoring of the cable to detect possible failures or even movements around the cable allows a proactive approach to fixing problems or mitigate scenarios. Much of the time, this can utilise many of the fibre optics already present in the cable when managed by suitable diagnostic and sensing capabilities. Following this, in the event of a failure, a proactive intervention and repair strategy is required, ideally with suitable vessels and technicians ready to deploy at minimal notice.

‘Muscular deterrence’

The Joint Committee report recommended ‘muscular deterrence’ and consequences for malicious damage, which sits firmly within the reams of defence and the navy. It also raised the importance point of ensuring that damaged cables are brought back online quickly. In addition to redundancy - the practice of designing a failsafe able to re-route the flow of data or power through an alternate route - the ability to respond and repair is critical.

Rather than being an issue of intentional damage and disablement, it is a fact of life. Both subsea power and communications cables do fail, with the main cause being a natural or mechanical breakdown or due to inadvertent human activity. While we must be alive to malicious damage, it would be incorrect to assume that this is the root cause of every severed line.

Building on a near two-decade legacy, Global Underwater Hub (GUH) is the leading trade and industry body for the country’s £9 billion subsea sector. Earlier this year we urged the Ministry of Defence (MoD) to engage with our sector to ensure the country is prepared for a potentially existential attack on national subsea infrastructure.

Areas for immediate attention

The publication of the Committee’s study is a very welcome step in this regard and we support many of the recommendations, with four areas of particular importance.

Dedicated repair ships, investment in cable skills training, integrating monitoring and alert systems, and seabed planning are all key to the integrity of our subsea assets.

Taken together, these measures do more than protect critical infrastructure, also laying the foundation for creating high-value jobs and economic opportunity in communities across the UK.

The scale of this opportunity is significant. Developing the workforce needed to install, repair and maintain undersea cable networks will increase demand for highly skilled roles in engineering, technology and maritime services.

These are long-term careers, in areas where demand is growing rapidly worldwide, and by building and retaining these skills at home, the UK can export expertise to international markets and secure an enduring competitive advantage.

While our subsea infrastructure may be invisible to most, it is indispensable to all. It underpins our defence, our energy security, our economy, key components in the very fabric of modern life. The UK has the expertise, the technology, the supply chain and the willingness to lead the world in this mission - we must bring that strength to bear.

Steve Fernie is Strategy and Policy Director, Global Underwater Hub