South China Sea: Underwater 'observation station' planned by Beijing

This May 2015 photo, shows land reclamation of Mischief Reef in the Spratly Islands by China. Photo/AP

Beijing is building an underwater observation system across the disputed East and South China seas in a move which could heighten tensions across the region.

According to State broadcaster CCTV, the "networks will also serve as a platform to provide long-term observation data and support experiments in the research of the maritime environments of the two seas."

The $400 million project has already sparked some concerns that it could be used detect the movement of foreign ships and feed information back to China.

The emergence of the network, which is expected to take five years to build, also comes as one expert warned Australia needs to be better prepared for China's "undersea military robots".

Beijing said the network, which will be built in the East China Sea and South China Sea, will "conduct around-the-clock, real-time, high-definition, multiple interface, and three-dimensional observations.

According to Greg Austin, a Professor in the Australian Centre for Cyber Security at the University of New South Wales (Canberra), Australia shouldn't feel any sense of imminent threat from China's undersea surveillance systems.China could also use the system as a form of surveillance on shipping movements and traffic which could impede the movement of US submarines across the sea.

However Prof Austin, an expert with 34 years of experience in China affairs, said we did need to be prepared in other areas.

"Australia needs to be prepared for China's undersea military robots, and will have to be better prepared for its undersea surveillance system," he said.

Prof Austin also pointed out that the United States already has a very powerful undersea surveillance system, called SOSUS, which has been in place for the past 50 years and in the South China Sea for almost as long.

"Since China is looking to become a major military power, it will develop similar capabilities, though not with the global reach of the US system," he said.

"The main difference now both for SOSUS and any new technologies for undersea surveillance is that they are supported by highly advanced information technologies giving real time correlation between SOSUS data and other forms of surveillance, especially space-based military satellites."

Prof Austin also said it was important to remember that the US Navy is far superior to the capability of the Chinese Navy and on current projections will remain so for decades.

He did however acknowledge there are potential downsides to this system.

"Like all forms of military surveillance and reconnaissance, while they have a potential negative effect on combat operations in wartime, in peacetime (as today) they do offer the sponsoring country added security that they know what other countries, potential adversaries are doing," he said.

A photo released last month shows Chinese structures and an airstrip on the man-made Subi Reef at the Spratly group of islands in the South China Sea. Photo/AP

'China an ocean power'

Jian Zhimin, dean of School of Marine and Earth Sciences, Tongji University told CCTV, the underwater observation system was a big step forwards for China.

"The devices will be placed down on the seabed through optical cables, in other words, build a laboratory undersea to collect and send data back to us," he said.

"China is an ocean power; it should have done more in oceanic studies in the past. An ocean power must be able to go to the high seas and go global."

University Professor Zhou Huaiyang said the system had benefits other than scientific research and could be used for mining, mapping or ocean rights protection.

Carl Thayer, a regional security analyst and emeritus professor at the University of New South Wales told CNN the China could use the network to lay sensors designed to detect warships and submarines.

"This would be of direct concern to the United States and other regional states that operate submarines," he said.

Dispute grows

The emergence of the observation system is the latest concern to be raised surrounding China's dominance in the South China Sea.

China has ongoing territorial disputes in both the East and South China Sea.

Just last month the controversy over disputed territory in the South China Sea heated up after a new report warned China has almost completed construction of three mysterious man-made islands.

The Washington-based Center for Strategic and International Studies (CSIS) analysed recent satellite photos and revealed runways, aircraft hangers, radar sites and hardened surface-to-air missile shelters have either been finished or are close to it.

The strategic bases will give China the ability to deploy combat aircraft and other military assets across the disputed region.

The islands - Subi, Mischief and Fiery Cross reefs - are part of the Spratly chain, which is claimed in whole or in part by China, the Philippines, Vietnam, Malaysia, Taiwan and Brunei.

The emergence of Beijing's man-made islands have sparked criticism from other nations including the US, who have accused China of further militarising the region.

According to the Lowy Institute, the South China Sea is a critical commercial gateway for a significant portion of the world's merchant shipping and an "important economic and strategic subregion of the Indo-Pacific" and the site of ongoing disputes.

It also contains rich fishing grounds as well as significant reserves of undiscovered oil and gas.