Just under four years after construction began, China has opened its longest underwater highway tunnel to traffic. The Taihu tunnel runs 6.65 miles under Lake Taihu, providing congestion relief and a shortcut between Shanghai and Nanjing, the capital of Jiangsu Province.
The six-lane tunnel contains more than 2 million cubic meters of concrete and is almost 60 feet wide. Xinhua news agency reported the builders used automatic steel processing equipment and AI that prevented the discharge of sewage and dust during construction. The tunnel is part of the 27-mile Changzhou-Wuxi Highway serving the cities near Lake Taihu, China’s third-largest freshwater lake. The tunnel’s ceiling features LED lights to keep drivers alert as they make their way through.
Construction of the Taihu tunnel cost around $1.56 billion, local government officials said. The lake is a water source for about 30 million people.