The solution, as Mao Zedong first said in 1952, is to “borrow a little water from the south.” Southern China is home to four-fifths of the country’s water sources, mostly around the Yangtze River Basin. It took another 50 years after Mao’s suggestion for China to start work on it. Finally, on Dec. 10, the first phase of the South-to-North Water Diversion Project (SNWDP) or Nanshuibeidiao, began operating.