China has initiated work on building the world’s largest water canal, which will carry a mammoth amount of water from the Three Gorges Dam all the way to Beijing as part of the nation’s South-to-North Water Diversion Project. 

The Yinjiangbuhan tunnel will connect the Three Gorges Dam and the Han River, before connecting to open canal heading north to Beijing. In total, the project will span 1,400 kilometers (870 miles) and cost an eye-watering $8.9 billion (£7.4 billion), but it will allow a constant water supply from the over-supplied eastern and southern China to areas of dryer conditions in the north.  

The announcement was reported by the South China Morning Post, which claims the massive tunneling project will provide a huge boost to food production in arid areas. 

Much of the tunnel will travel deep underground, reaching depths of 1,000 meters (3,300 feet) below the surface. Such an undertaking will likely utilize the latest tunneling equipment, as intense pressures 1 kilometer (0.6 miles) below the surface will make for slow progress – even with such equipment, the project is still expected to take around a decade. 

The South-to-North Water Diversion Project is the largest water diversion project ever undertaken. It was originally thought up around 50 years ago and work on it has only recently begun. The Yinjiangbuhan tunnel is just a small piece of the overarching puzzle that will make up the ambitious $62 billion project. Once complete (likely around 2050), all four of China’s major rivers – the Yangtze, Yellow River, Huaihe, and Haihe – will be linked and it will divert almost 45 billion cubic meters of water northwards each year. 

With the construction of the Yinjiangbuhan tunnel, food production could be boosted by as much as 540 million tonnes each year, as much as the whole of the US currently produces, reports Interesting Engineering. The resulting impacts should improve conditions in the northern and easterly parts of China, bringing improvements to people's quality of life and the economy.