China is developing a record-breaking dredger 50 per cent more powerful than its existing "super island builder", the project's chief engineer said.

The new self-propelled suction dredger being developed will feature a 10,000kW reamer, the first in the world, according to Qin Bin, chief engineer of the Tianjin Waterway Bureau, a subsidiary of the state-owned China Communications Construction Company (CCCC).

In comparison, its predecessor the Tian Jing - the main vessel involved in building China's controversial artificial islands in the South China Sea in 2013 and 2014 - has a reamer power of 4,400kW and the Tian Kun, a vessel commissioned in 2019 as the most powerful of its kind in Asia, has 6,600kW in power.

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Both Tian Jing and Tian Kun are owned and operated by the Tianjin Waterway Bureau Co, which has the most powerful dredger fleet in the world.

"The development of the new vessel is not just a simple enlargement in terms of reamer power, hull size etc, but a qualitative leap forward," Qin, also a member of the Chinese People's Political Consultative Conference, said on the sidelines of the CPPCC annual session.

A dredger is a vessel that can blast through the rock on the bed of a river or the sea with its reamer, suck up rocks and sand and pump them through a pipe over a distance. They are used to clear navigation waterways or to build artificial islands.

China has invested heavily in its dredging industry and has built about 200 vessels since 2006 to become one of the world's biggest dredger manufacturers.

Qin said China's dredger industry must strengthen its self-sufficiency in core technology development to become the industrial leader of the world.

The Tian Jing, or "Celestial Whale", was jointly designed by Shanghai Jiao Tong University and Germany's Vosta LMG, and commissioned in 2010. It can excavate 4,500 cubic metres (159,000 cubic feet) of sand per hour, and its powerful pump can send the sand up to 6km (3.7 miles) away.

This unique instrument can reclaim land faster, dredging in one spot and refilling in another without the need to transport landfill material from elsewhere.

The ship reportedly spent 193 days moving among five reefs in the Spratly Islands between September 2013 and June 2014. Its team broke the underwater coral reefs and sucked and stacked them to construct the submerged atolls - Fiery Cross, Mischief and Subi - into the largest land features in the South China Sea and featuring airports, radar arrays and missile positions.

After the "Great Wall of Sand" was completed in the disputed waters, the Tian Jing Project won the highest prize in China's National Science and Technology Progress Award in 2019.

The domestically designed Tian Kun vessel, completed in 2017, upgrades the capacity to 6,000 cubic metres per hour, with an ability to send material 15km and dig 35 metres under the sea floor.

This article originally appeared in the South China Morning Post (SCMP), the most authoritative voice reporting on China and Asia for more than a century. For more SCMP stories, please explore the SCMP app or visit the SCMP's Facebook and Twitter pages. Copyright © 2023 South China Morning Post Publishers Ltd. All rights reserved.

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