The TBM broke through on the final tunnel on Daling Mountain in Dongguan, Guangdong province last weekend.

The Y35.4bn (US$4.8bn) scheme, one of China’s 172 major water resource projects, stretches 113km and features 48 tunnels at depths of 40m to 60m.

It will divert more than 1.7 billion m3 of water a year from the Xijiang River water in the west of Guangdong to the Dongjiang basin to alleviate water shortages in the cities of Guangzhou, Shenzhen and Dongguan. It will also provide an emergency water supply for Hong Kong.

Construction started in 2019 and the scheme is expected to be operational by the end of next year.