BEIJING - China's water resources imbalances between the North and South may worsen due to global climate changes and economic activities, said Vice-minister of Water Resources Hu Siyi.

Typically, China's north is dry while its south has abundant water supplies.

HK prepares for global yuan Related readings:  Water diversion investment to top $20b  More resettled for S-N water diversion project  Water diversion project moves tide of people  Pollution still hinders water diversion in E China

China will face unprecedented challenges in saving water in the next five-year plan from 2011 to 2015, said Hu at a national water-saving meeting in Zhengzhou, capital of central China's Henan Province, late September.

Compared with the 1956-1979 period, rainfall in the Yellow River, Huaihe River, Haihe River and Liaohe River vallies in the 1980-2000 period had dropped six percent on average and river and lake water resources decreased 17 percent in these areas, according to figures from the Ministry of Water Resources.

China's accelerated urbanization has pushed up demand for water.

If the population in Beijing keeps on climbing, the water brought by the near completed South-to-North Water Diversion Project would not be enough, Hu said.

China's water-saving targets during the 12th five-year plan from 2011 to 2015 include a 30-percent cut in water use for every 10,000 yuan ($1,490) of gross industrial output, Hu said.