(Bloomberg) -- China plans to expand the world’s largest water-diversion project, aiming to double the amount of water it can transfer from the flood-prone south to its dry northern cities, government officials said Thursday.

The first phase has transferred a total of 30 billion cubic meters of water to northern China in the past five years since it was completed, benefiting 120 million people in 40 cities and helping boost local economies and employment, Jiang Xuguang, vice minister of the Ministry of Water Resources, told a press conference in Beijing.

World’s Largest Water Diversion Plan Won’t Slake China’s Thirst

The second phase of the South-to-North Water Diversion project will cover both the eastern and middle routes. The eastern route will raise annual delivery capacity from 8.77 billion cubic meters to 16.5 billion cubic meters, and will supply water to Shandong and Anhui provinces and increase supplies in Tianjin, Beijing and Hebei, said Shi Chunxian, head of the ministry’s planning department. A new 1,785 kilometer-long water channel will be built with 25 pump stations.

For the middle route, several reservoirs will be built to store water to ensure there is continuous supply and connect the Han and Yangtze rivers, Shi said.

Shi played down the ecological impact on the Yangtze River of the expansion of the project and said China transfers less than 2% of the river’s flow. The ministry didn’t give any costs for the second-phase expansion or when the construction would be completed, and said the western route of the project is still being studied.

The western section, which would divert water from three tributaries of the Yangtze River to help replenish the Yellow River, is the most controversial part of the project.

To contact Bloomberg News staff for this story: Niu Shuping in Beijing at nshuping@bloomberg.net

To contact the editors responsible for this story: Anna Kitanaka at akitanaka@bloomberg.net, James Mayger, Nicholas Larkin

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