Stalking the Seabed: How Russia Targets Critical Undersea Infrastructure

Deepwater danger: a Russian Kilo-class submarine pictured transiting the English Channel in 2018. Image: LA(Phot) Guy Pool / Defence Imagery / OGL v1.0

With attention increasingly focusing on Russian activity against Western critical infrastructure at sea, what is the nature of the threat and how can it be countered?

The recent disclosure of Russian naval activity in the vicinity of key maritime infrastructure in the North Sea including cables, windfarms and pipelines should not necessarily come as a surprise. Russia has spent a considerable amount of effort investing in capabilities that would allow it to pose a threat to European critical infrastructure, and has viewed this as an imperative since the Soviet era. An emphasis on demonstrating the ability to target economically vital assets can be found in Russian thinking on escalation management, which presumes – correctly or otherwise – that the ability to inflict economic harm represents a means of containing local conflicts on Russia’s periphery by deterring external intervention. In a conflict with NATO, damage to infrastructure at sea along with the targeting of infrastructure ashore would be a key part of Russia’s overall war effort, aimed at gradually eroding popular support in the West. This article will examine some of the tools at Russia’s disposal for the prosecution of a campaign against European infrastructure at sea, the organisational structures that manage them, and the ways in which the threats they pose can be mitigated.

Russian Seabed Warfare: An Intelligence Function, not a Naval One

The task of maritime special operations is spread across different organisations within the Russian system, including the Russian Navy and the Main Directorate for Deep Sea Research (GUGI). These organisations field somewhat different capabilities and likely own different aspects of the function of maritime sabotage. Notably, however, although the Russian Navy plays a key operational role, the Ministry of Defence (MoD) and the GRU – Russia’s foreign military intelligence agency – appear to control activity in organisational terms, both through the GUGI and the Russian Naval Staff’s Intelligence Directorate.

The GUGI represents a particularly interesting and specialised body. Founded within the navy in 1965 and given its present organisational status in 1975, the organisation exists independent of naval command and has the status of a directorate within the Russian MoD. While independent of the navy, it draws personnel from the 29th Separate Submarine division, a formation based at Olenya Guba which exists to operate platforms for the GUGI. The body operates a number of specialised submarines including the Paltus, X-Ray, Kashalot and Losharik (which is currently undergoing repairs). These submarines share the characteristic of being titanium-hulled, enabling them to sustain the pressure of operating at extreme depths. In the case of the Losharik, the submarine also has a unique internal arrangement, with its hull comprised of seven joined spherical chambers which distribute pressure, enabling it to operate at depths of up to 2,500 metres. The submarines have typically been equipped with manipulator arms, and in the case of the X-Ray, a diver lock-out. Though nuclear-powered, these submarines are relatively small, making the sustainment of crews for extended periods difficult – something experienced by the US Navy with analogous vessels such as the NR-1. As such, they need to be supported by motherships on longer voyages. For this role, the Soviets and then the Russians have typically used stretched versions of retired nuclear-powered ballistic missile submarines (SSBNs) such as the Yankee class and nuclear-powered cruise missile submarines (SSGNs) such as the Oscar class. The GUGI’s two current motherships, the Belgorod and the BS-64 Podmoskovye, are respectively a stretched Oscar-class SSGN and a Delta-class SSBN.

In addition, the GUGI operates surface vessels that nominally act as research vessels to gather intelligence. These include the Yantar, which received attention for activity around sensitive cables near the UK in 2019. The vessel is equipped with a variety of sensors and appears capable of acting as a host vessel for the Pr18610 – a three-man deep-diving submersible capable of operating at depths of 20,000 feet. In addition, the vessel likely hosts a range of remotely operated and autonomous underwater vehicles.

While understandable attention has been paid to the GUGI’s likely role in damaging critical infrastructure in the event of an escalating conflict, it is important not to assume that this is its only function. The organisation is tasked with the emplacement of sensors associated with Russia’s Harmony network, surveillance of foreign assets in Russian waters, and the removal of foreign surveillance assets, including taps on wires. In addition, the Belgorod will apparently host a part of the Russian nuclear arsenal in the form of the Poseidon nuclear torpedo.

In a conflict with NATO, damage to infrastructure at sea would be a key part of Russia’s overall war effort, aimed at gradually eroding popular support in the West

The time that naval personnel spend within the GUGI sees them paid considerable salaries without breaking the relationship between rank and pay, by treating their effective salaries as a deployment bonus related to the time they spend at extreme depths. As a result, in 2012, GUGI personnel were earning 600,000 roubles a month (around $20,000 at the time). The reason for this level of compensation is that the organisation is an extremely specialised one. During the Soviet era, in order to qualify, an individual had to be an officer and have served for five years within the submarine service, and would then have to go through a gruelling course based on the training of Soviet cosmonauts. The list of individuals killed in the 2019 fire which broke out on the GUGI deep-diving submarine Losharik – all officers – suggests the force remains a highly specialised one.

The GUGI does not own the entirety of the task of maritime sabotage, however. A key role is also played by the Intelligence Directorate of the Main Staff of the Russian Navy. Since 1977, the director of Russian Naval Intelligence has also typically been the deputy director of the GRU, and the Intelligence Directorate was made subordinate to the fifth directorate of the GRU, which reflected the subordination of naval intelligence to the latter – a process which accelerated under the tenure of Admiral Vladimir Chernavin.

Notably, the Russian vessel most recently spotted near European infrastructure – the Akademik Vladimirsky – belongs to the Russian Navy and not to the GUGI. Though the precise suite of sensors on board the ship are unknown, in a 2012 research expedition to the South Pole it deployed a proton magnetometer, which could also be used to discover metallic objects on the seabed such as pipelines. During the Cold War, the Soviet Navy also maintained a number of auxiliary surveillance vessels based on common trawlers, which were tasked with a range of intelligence gathering functions, and regional fleets controlled Spetsnaz units with an explicit sabotage role. Moreover, the Navy was charged with managing relations with Soviet fishing fleets, which could be co-opted into both intelligence gathering and sabotage functions. The recently revealed use of civilian vessels to survey wind farms in the North Sea suggests that this practice has been continued and is likely a task of the Navy rather than the GUGI. The Spetsnaz units controlled by regional fleets can be inserted into theatre using a range of mechanisms such as swimmer delivery vehicles, and can be used for both surveillance and covert operations against military and civilian targets. The Northern Fleet’s Spetsnaz have trained for operations against SOSUS, and those of the Baltic Fleet have allegedly been involved in covert sabotage. Like all Spetsnaz, these units are under the ultimate control of the GRU.

The bifurcation of responsibilities between naval intelligence, which answers to the GRU, and the GUGI – which apparently sits as a directorate within the Russian MoD – would seem to create an artificial divide between assets performing similar functions. There is nothing entirely unusual about an intelligence agency controlling assets that are especially sensitive; the CIA, for example, directly controlled the U-2 spy plane and directed many of the operations of spy submarines like the NR-1. However, leaving some assets with the Russian Navy (albeit under ultimate control of the GRU) while conferring others on the GUGI is an interesting organisational choice.

One possibility is that sensitivity is the primary consideration, although given the likely involvement of the GRU in highly sensitive unconventional operations including both sabotage and assassinations, this seems unlikely to be the case. Another possibility is that because the fifth directorate is responsible for operational intelligence, its responsibilities include more strictly military tasks such as trailing Western naval assets, whereas the GUGI retains control over those assets needed for activities that are more strategic. A final reason why these assets were removed from the navy’s control may have been the reassertion of control by the Russian General Staff over the Soviet Navy under the tenure of Marshal Nikolai Ogarkov and then-Soviet Defence Minister Dmitri Ustinov.

Navies will likely need to have the organisational structures to coordinate with a broader range of actors in order to meet the challenge of maritime sabotage

In any case, the GUGI appears capable of organising its assets along with naval capabilities on a task-specific basis. For example, one investigation of the Nord Stream blasts alleged that elements of both Unit 45707 and the 313th Special-Purpose Detachment for Combating Underwater Sabotage of the Baltic Fleet were involved. As such, it would appear that the GUGI can draw on assets from the wider fleet as needed.

Challenges to Critical National Infrastructure

The different components of Russia’s overall maritime sabotage capability pose different challenges to the critical infrastructure of European countries, which encompasses undersea cables, gas pipelines and windfarms, among other things.

Deep-diving submarines can sever cables at depths which make repairs extremely difficult. They can also tap sensitive undersea cables. However, these capabilities are limited in number and operated by only a few very specialised individuals. The GUGI, moreover, has a number of additional operational obligations, such as maintaining Russia’s undersea sensor networks and conducting surveillance near its maritime bastions. Additionally, the motherships on which deep-diving submarines depend for longer transits, such as the Belgorod, are likely to be detectable by NATO anti-submarine warfare assets to roughly the same degree as the submarines on which they are based were. A more pressing challenge than detecting capabilities is establishing rules of engagement, particularly in peacetime. In territorial waters, countries can prosecute foreign submarines they detect aggressively – something the Soviets frequently did with US submarines during the Cold War, and vice versa. In international waters, however, this is likely to be more of a challenge. That said, Western navies can complicate the activity of Russian special purpose submarines in other ways. For example, activity at or near the sensor networks for which the GUGI is responsible can force it to allocate scarce resources to more defensive functions. Alternatively, civil-military partnerships can be used to remove deniability. To use an example, the Italian Navy recently struck an agreement with the country’s largest internet provider to share data. Many private-sector actors operate sensors, including unmanned underwater vehicles and pressure detectors, to monitor damage. If claims made by a navy regarding the activity of a submarine in the vicinity of undersea cables can be verified through a private partner, this could raise the risk of attribution and set the conditions for other policy instruments such as sanctions to be used.

The challenge posed by a combination of auxiliaries and surface vessels operated by the Russian Navy is a somewhat different one. These vessels cannot necessarily damage infrastructure such as undersea cables at depths that would make repairs especially difficult, but by virtue of being inconspicuous they are harder to track and identify. As the ambiguity around the Nord Stream blasts illustrates, this can pose a substantial challenge for attribution. That being said, there are also methods of interdiction against surface vessels that do not exist for subsurface assets. The 1884 Cable Convention, to which Russia is a signatory, allows navies to board and search ships in international waters if they believe them to be tampering with undersea cables – a right the US has exercised. Similarly, the UN Convention on the Law of the Sea (UNCLOS) allows countries to constrain the activities of civilian vessels conducting surveillance relevant to economic exploitation within their exclusive economic zones (EEZs) – and most of these activities overlap substantially with the sort of surveillance a ship would need to do to survey infrastructure. In the Baltic and North Seas, which are almost entirely straddled by Western EEZs, this could be a basis for significantly limiting the freedom of action of Russian auxiliary ships while remaining within international law. To be sure, UNCLOS allows military vessels the right of surveillance within EEZs, but such vessels are readily identifiable in both peacetime and conflict, enabling attribution in peacetime and interdiction above the threshold of war.

The challenge with regards to auxiliary ships is primarily one of classification. This challenge is in some ways not dissimilar to constabulary activities such as counter-smuggling or counterpiracy: it requires a suspect vessel to be identified in the midst of a large number of ships conducting normal economic activity. A number of measures could make this more robust. For example, we might consider recent work on the use of machine learning as well as more traditional algorithmic tools to identify irregular patterns of activity by a vessel. That said, to build the body of data needed to support these processes, Western navies will need presence in key theatres and greater levels of situational awareness than naval assets alone can provide. As the efforts of CTF-151 in the context of counterpiracy have illustrated, the sheer number of vessels needed for this level of presence means such efforts must necessarily be multinational. Given that NATO’s standing maritime groups typically do not control the assets needed for these functions in peacetime (though this may be changing), such functions could be achieved on a regional basis through framework nation constructs. In addition, the tasks of both surveillance and attribution would likely be made considerably easier if assets from across and beyond militaries could be used to both achieve domain awareness and attribute malign activity. Recent efforts by countries such as Italy to build relationships between its navy and the private sector stand out as examples. Similarly, the decision by France to make seabed security a national strategic concern coordinated across government may represent a step towards achieving this imperative. While naval assets will remain crucial for tasks from surveillance to interdiction, navies will likely need to have the organisational structures to coordinate with a broader range of actors in order to meet the challenge of maritime sabotage.

This article is part of the Russia Military Report series.

The views expressed in this Commentary are the author’s, and do not represent those of RUSI or any other institution.

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Dr Sidharth Kaushal

Senior Research Fellow, Sea Power

Military Sciences

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