Backgrounder: The South-to-North water diversion project's middle route

China's south-to-north water diversion project, the world's largest, is designed to take water from the country's longest river, the Yangtze, through eastern, middle and western routes to feed dry areas in the north, including capital city Beijing.

The project, with an estimated cost of 500 billion yuan (about 81.4 billion US dollars), started with the construction of the eastern route in 2002 and the middle route in 2003, while the western route in its pre-construction stage.

Upon completion, the project is expected to divert up to 44.8 billion cubic meters of water per year to more than 10 provinces and cities, benefiting nearly 100 million people. Up to 600,000 jobs are also estimated to be created.

The major parts of the eastern route are located in the provinces of Jiangsu and Shandong.

The middle route, the most attention-grabbing of the three routes due to its role in feeding water to the national capital, started supplying water Friday as part of the project's first phase.

The main canal of the middle route is 1,432 km in length, featuring a 1,196.36-km-long open channel.

The first phase project will see a massive 9.5 billion cubic meters of water per year pumped through canals and pipes from the Danjiangkou reservoir in central China's Hubei Province to the northern provinces of Henan and Hebei and to Beijing.

After completion of the second phase of the route, up to 13 billion cubic meters of water will flow north each year.

As of September, a total of 210.18 billion yuan had been invested in the first phase project of the middle route.

TIMELINE

-- In October 1952, the idea of diverting water from the resource-abundant south to the north was first envisioned by China's late chairman Mao Zedong.

-- On June 5, 2000, after decades of research and discussion, the South-to-North water diversion project was set to include three routes -- the eastern, the middle and the western -- to take water from the Yangtze River.

-- On Dec 23, 2002, the South-to-North water diversion project was officially approved by the State Council.

-- On Dec 27, 2002, construction of the world's largest water diversion project started from the eastern route in Shandong and Jiangsu.

-- On Dec 30, 2003, construction of the first phase project of the middle route began.

-- On Sept 26, 2005, a project began to heighten the dams of the Danjiangkou Reservoir, so as to expand the storage capacity of the water source of the middle route.

-- On Feb 26, 2009, major work on the middle route involving seven provinces started.

-- On March 31, 2010, all 54 dams of Danjiangkou Reservoir were raised to their highest level, from 14.6 meters to 176.6 meters, to shore up to 29 billion cubic meters of water from rivers including the Hanjiang River, a major tributary of the Yangtze River.

-- In September 2012, relocation of residents near the Danjiangkou reservoir area was completed.

-- On Dec 25, 2013, the main work of the middle route of the South-to-North Water Diversion Project was completed.