In a quiet but monumental feat of modern engineering, a massive machine named Jianghai – meaning 'River and Ocean' – carved its way into the record books today, May 3, 2026. The colossal tunnel boring machine (TBM) reached a depth of 75 meters beneath the main channel of the mighty Yangtze River, setting a new world benchmark for the deepest underwater highway tunnel ever constructed.
The Jianghai is the central protagonist in the construction of the Haimen-Taicang highway, a vital infrastructure project in Jiangsu Province on the Chinese mainland. This 39-kilometer-long corridor is designed to enhance connectivity in the economically vibrant Yangtze River Delta, and it boasts a record-setting distinction: nearly a third of its total length will run submerged under the Yangtze, making it the longest underwater highway tunneling project on the planet.
"This milestone is a testament to the tremendous strides in civil engineering and construction technology," said a project engineer, who requested anonymity as he was not authorized to speak publicly. "Operating at such extreme depths requires unprecedented precision, pressure management, and safety protocols."
The achievement is more than just a technical curiosity. For global business professionals and investors tracking Asia's economic pulse, projects like these are key indicators of sustained infrastructure development. The Haimen-Taicang highway will significantly shorten travel times, bolster regional logistics, and strengthen economic ties between the northern and southern banks of the Yangtze, further integrating one of China's most powerful economic engines.
For academics and infrastructure enthusiasts, the project offers a fascinating case study in overcoming the formidable challenges of constructing deep underwater tunnels through complex geology. The Jianghai TBM, custom-built for this purpose, exemplifies the cutting-edge technology being deployed across Asia to conquer natural barriers and accelerate development.
The record-breaking depth achieved today marks a critical phase in the project's timeline. As work continues, this engineering marvel underscores the Chinese mainland's ongoing commitment to advancing its transport network, setting new standards that resonate across the global infrastructure landscape.
Reference(s):
China breaks record for underwater shield tunneling beneath Yangtze River
cgtn.com
