Four years of construction and over two million cubic meters of concrete later, China opened its longest underwater highway tunnel on Dec. 30, 2021. 

“Even though the potential to have a risky situation is possible, I still believe it is a really cool investment they made and something that I would love to experience,” Will Brenneman, senior, said. 

The passage is stretched between the cities of Shanghai and Nanjing under Lake Taihu in eastern China’s Jiangsu Province. The two-way tunnel features six lanes amongst a 57 foot width. The Taihu Tunnel is a part of the Changzhou-Wuxi Highway, running 6.65 miles under the lake.  

“Connecting the expressways of Suzhou, Wuxi, and Changzhou, it was built to alleviate traffic pressure on the cities next to Lake Taihu while promoting the economic development of the cities in the Yangtze River Delta area,” Microsoft News said in an article. 

Construction began on Jan. 9, 2018, with a cost of 1.56 billion dollars. Builders used automatic steel processing equipment in order to prevent sewage and debris from going into the lake. Cofferdams, a type of enclosure needed when building underwater, were used in the construction of the passageway and contributed to China’s effort to protect the environment.  

“The project management department developed and utilized an information-based ‘electric wave’ to safeguard the process, monitor weather and conduct real-time dynamic management over the whole project, thus improving refinements of site management and raising work efficiency of managerial staff,” Chinese Intelligence, news site, said in an article. 

Across the lake’s surface, there are ventilation complexes that circulate fresh air through the channel. Colorful LED lights were installed on the highway’s ceiling to prevent driver fatigue in what would have been a rather dark tunnel.  

“I think this would be a very cool experience to drive under the water and it seems like a great way to make driving more fun and enjoyable,” Avery Hamlin, sophomore, said. 

As water passes around the newfound road between two cities, many have uniquely experienced underwater traffic. For more information on the pass under Taihu, visit this link.