Two subsea cables off Perth's coast suffered faults over the weekend inside a designated protection zone, prompting urgent calls for a federal investigation and highlighting Australia's vulnerability to infrastructure disruption. The incidents occurred in close proximity and in rapid succession, raising questions about deliberate interference.
Bevan Slattery, chief executive of Subco, the company that owns the cables, wrote on LinkedIn that both faults happened "straight after each other and in close proximity to each other" within the Submarine Cable Protection Zone off Perth. He called the development concerning and urged the Australian Federal Police to investigate urgently. An AFP spokesperson confirmed the agency had received a report of crime in relation to the matter and said the report is currently being assessed based on the information provided.
Critical Infrastructure at Risk
Australia has 16 subsea cables that carry 99 per cent of the country's international communications, according to David Brewster, senior research fellow at the National Security College at the Australian National University. He told 102.5 ABC Perth that these cables are fundamental to the Australian economy and daily life. "If they were to be disrupted or cease, it would have a massive impact on our country," Dr Brewster said.
Most Australians don't realize the extent of their dependence on these cables. "Just about every app, every cloud-based application, every Google search, etc, depends on international communications in one way or another," Dr Brewster said. The cables lie on the ocean floor, are about the width of a garden hose, and can be easily cut by accident by ship's anchors. They can also be cut deliberately.
Foreign Threats and Precedents
Dr Brewster pointed to numerous incidents in Europe and around Taiwan over the last three or four years of cables being cut. "It's difficult to be absolutely certain of the reasons in some of these cases, but in a great number of cases, it's fairly obvious that they were done by state actors, Russia and China," he said.
The damaged cables were inside the Perth Cable Protection Zone, which extends 60 nautical miles off City Beach, to a depth of 2,000 metres and one nautical mile each side of the cables. Yet even within this designated zone, the infrastructure proved vulnerable. Dr Brewster said it's extremely difficult to stop a determined adversary from cutting the cables or launching cyber attacks on them.
Ownership and Governance Gaps
The cables are all privately owned and increasingly owned by US tech companies such as Meta, Google or Amazon. "That does create other risks as well, because it means that not only are these cables privately owned, but they're also privately owned by, in many cases, foreign companies," Dr Brewster said. The government has very limited power to actually influence what is being done into how these cables are operated or repaired.
No single government department or agency is responsible for the cables. Multiple departments have jurisdiction over some aspects of the subsea cable sector, creating confusion about accountability. "We need to nominate an agency to take responsibility for protecting the cables and any response," Dr Brewster said. "Who do you call when a cable is being cut or disrupted? For many private operators, it's really not clear to them who takes responsibility within government."
Dr Brewster said the best protection strategy would be to lay more cables. "The more cables you have, the less vulnerable you are, and Australia certainly needs a lot more cables than it currently has to mitigate the threat," he said. Mr Slattery was unavailable to be interviewed.
Why This Matters:
This incident exposes fundamental weaknesses in Australia's critical infrastructure governance. The fact that 99 per cent of international communications flow through just 16 privately owned cables—many controlled by foreign tech giants—represents a significant national security vulnerability. The government's limited authority over these essential assets raises serious questions about sovereignty and emergency response capability. With state actors like Russia and China demonstrating willingness to target undersea cables in other regions, Australia's fragmented regulatory approach and lack of designated oversight authority creates dangerous ambiguity. The private sector built this infrastructure, but the absence of clear government responsibility for protection and incident response leaves both operators and the nation exposed. Determining whether these Perth faults resulted from accident or deliberate action will be critical, but the broader issue is institutional: Australia needs consolidated authority, expanded redundancy, and clearer protocols to protect infrastructure that underpins the entire digital economy.