2025 in review: Private investments supercharge subsea cable buildouts

　　The world's largest hyperscalers remain the largest investors in new submarine cable systems in 2025 as they race to ensure they have the essential infrastructure in place to support their growing networks of data centers and cloud regions.

　　Google Cloud announced in late November its plan to construct TalayLink, a new subsea cable connecting Australia and Thailand. The cable will create a new, diverse route to Thailand via the Indian Ocean, west of the Sunda Strait. Many existing subsea cables currently pass through this area. Google Cloud also announced plans for new connectivity hubs in Mandurah, Western Australia, and southern Thailand.

　　The Google Cloud announcement came a week after Meta completed its 45,000-kilometer 2Africa subsea cable, the largest subsea cable network. The cable currently runs across 33 countries, forming a continuous system that connects East and West Africa and links Africa to the middle East and South Asia.

　　Meta's next submarine cable project, dubbed Project Waterworth, will span five continents and stretch 50,000 kilometers, making it the longest yet. It will be Meta's first cable system. Although specific details have not been disclosed, reports estimate the project's cost at $10 billion.

　　"AI is increasing the need that we have for subsea infrastructure," Alex Aime, Meta's vice president of network investments, told CNBC in a recent interview. "Oftentimes, when people think about AI, they think about data centers, they think about compute, they think about data. But the reality is, without the connectivity that connects those data centers, what you have are really expensive warehouses."

　　Other hyperscalers are also working on subsea cable projects. In early November, AWS announced its first independently undertaken subsea cable project. Called Fastnet, the project will connect Maryland's Eastern Shore to county Cork, Ireland, and is expected to be operational by 2028.

　　Microsoft announced two separate deals in May with Hibernia and Aqua Comms, investing undisclosed sums in subsea cables with each company. These projects aim to connect Microsoft's data center infrastructure in North America with Ireland and the United Kingdom.

　　According to the latest figures from TeleGeography, investment in new subsea cable projects is expected to reach approximately $13 billion between 2025 and 2027. This is nearly double the amount invested between 2022 and 2024. To date, the telecommunications data provider has mapped 597 cable systems and 1,712 landings, all of which are currently active or under construction.

　　Added capacity along intra-Asian routes

　　Overall, 2025 was a transformative year for the submarine cable industry, characterized by unprecedented private investment, AI-driven infrastructure demands, technological innovation and heightened security considerations. The industry is rapidly evolving from traditional telecom-led consortia to tech giant-dominated private networks supporting the global digital economy.

　　Several consortium-led submarine cable projects have launched in the past 12 months, providing data-intensive regions, such as the Asia-Pacific, with a much-needed boost in IT capacity.

　　Various sections of the 10,000km Asia Direct Cable (ADC) system became operational in the first half of the year, following its launch in November 2024. The 10,500km Southeast Asia-Japan Cable 2 (SJC2) became operational in July, connecting Singapore, Hong Kong, China and Japan. And the Southeast Asia-Hainan-Hong Kong (SEA-H2X) cable project, led by China Mobile, is expected to be fully completed by the end of 2025.

　　Most of the newly launched cable systems include Singapore in their main trunk, highlighting the city-state's role as a major connectivity hub. This year alone, the city-state has seen at least five subsea cable projects come into operation, including the 20,000-kilometer Bifrost Cable System and the 17,000-kilometer Echo Cable System.

　　Four months ago, a Singtel-led consortium announced the Asia United Gateway East (AUG East) submarine cable system, an 8,900km system that will increase capacity in East Asia.

　　Geopolitical tension in the Taiwan Strait

　　Tensions between China and Taiwan escalated earlier this year when a civilian cargo ship was suspected of completely severing the Taiwan-Penghu No. 3 submarine cable beneath the waters off Taiwan's southwestern coast near the Penghu Islands.

　　Experts describe this incident as an example of China's "gray zone tactics" against Taiwan. These tactics involve using civilian vessels to conduct activities that fall below the threshold of conventional warfare but still cause significant disruption.

　　Between January and February 2025, Taiwan experienced four separate incidents of submarine cable disruptions, prompting the government to allocate additional funds to subsidize operators, such as Chunghwa Telecom, to build new international submarine cable landing stations and backup facilities. The country's Ministry of Digital Affairs is also pushing for diversified communication systems as a backup in case of submarine cable failure. These backup systems will consist of microwave communication and satellite systems.

　　In October, the Taiwanese legislature moved to amend seven laws governing submarine cables to better protect critical infrastructure. The proposed amendments, which have passed a preliminary review, aim to impose the same penalties for damaging submarine cables as for damaging water and natural gas pipelines.

　　Suspected sabotage of submarine cables in Taiwan and the Baltic Sea has prompted the US Federal Communications Commission (FCC) to adopt comprehensive new rules that will transform the country's submarine cable infrastructure regulations. FCC Chair Brendan Carr told CNBC that the FCC is taking steps to ensure that the hardware itself is not compromised by prohibiting the use of Huawei, ZTE and other questionable "spy gear" in undersea cables.

　　$3B price tag to upgrade aging cable repair fleet

　　A report commissioned by the SubOptic Association predicted that 47% of the vessels in the global cable fleet will have reached the end of their 40-year service lifespans by 2040. The report also estimated that 1.6 million kilometers of new cable systems will be installed between now and 2040, which is roughly twice the amount being taken out of service.

　　The forecast predicts a 48% growth in the volume of deployed cable kilometers over the period, while annual repairs are expected to increase by 36%. The report authors, consultancy firms TeleGeography and Infra-Analytics, caution that this disconnect increases the potential for cable faults, particularly in areas such as the southwest and northwest Pacific, which require a disproportionate number of repairs.

　　"Meeting the challenges of the rapidly expanding submarine cable ecosystem and an aging cable ship fleet will require an investment of roughly $3 billion to sustain current service levels and avoid repair delays. This would entail the acquisition of 15 replacement ships and five additional ships to serve the global subsea internet infrastructure," the report said.

　　Recognizing the untapped potential of the subsea cable repair sector, Singapore-based Keppel acquired a 100% stake in Global Marine Group (GMG), which provides maintenance, emergency repairs and fiber-optic cable installation worldwide. GMG is one of the world's largest independent providers of subsea cable solutions with a fleet of six vessels and a strong track record of contract renewals with telcos, hyperscalers and global equipment suppliers.