Engineering Wonder: China to build world's longest underwater tunnel

New Delhi: China plans to build the world's longest underwater tunnel beneath the Bohai Sea by 2026, connecting the port cities of Dalian in Liaoning province and Yantai in Shandong province. The blueprint of the ambitious project is expected to be submitted to the State Council of the People's Republic of China in April, the China Daily reported on Friday. “Once approved, work could begin as early as 2015 or 2016,” Wang Mengshu, a tunnel and railway expert at the Chinese Academy of Engineering, who has worked on the plan since 2012. Wang said that the 123-km underwater tunnel will cost around 220 billion yuan ($36 billion). The length of the tunnel will be more than the combined length of the world's two longest underwater tunnels – Japan's Seikan Tunnel and the Channel Tunnel between Britain and France. Wang told the newspaper that journey time would be cut to 40 minutes. The tunnel follows the coastline to the west of Yantai, before veering north across the Bohai Sea. The tunnel would surpass the combined length of the world's two longest tunnels, Japan's Seikan Tunnel linking Honshu and Hokkaido and the Channel Tunnel between Britain and France. It would drastically cut the current travel time between the two cities, separated by a 1,400-km drive or about 8 hours by ferry. Three tunnels in total will be built at least 30 meters below the sea bed, two about 10 meters in diameter, and a third between them for maintenance and emergency vehicles, the China Daily added. The tunnel runs across two earthquake fault lines, and in 1976 the industrial city of Tangshan in Hebei province – between Shandong and Liaoning – was levelled by an earthquake with a magnitude of at least 7.5, although figures vary.