Sanya's 1st underwater tunnel to begin operating in 2026

An aerial view of Sanya River Estuary Passage Project's construction site. [Photo/WeChat account: syrbgfwx]

The Sanya River Estuary Passage Project, a key provincial initiative and also Sanya's first underwater tunnel project, is expected to be around 50 percent complete by the end of this year and open to traffic in June 2026.

The tunnel has a total investment of 2.68 billion yuan ($371.74 million) and length of 3.12 kilometers. It includes one main line, three ramps, and eight entrances and exits.

It will connect the west bank area with the Nanbianhai area, reducing the distance for residents and tourists by 5 km and saving 15 minutes in commuting time.

The tunnel is the first in the country to adopt a construction technique using a pipe umbrella structure and freezing method, as well as a three-pipe bite-in top-down construction technique.

 
This method ensures that the construction will not affect the entry and exit of yachts and ships at the port and will not compromise the integrity of Sanya's coastal cityscape.