An upriver reservoir began to discharge fresh water Tuesday into the Pearl River, which has suffered from a salt tide for two weeks, in a bid to increase drinking water supply to the densely populated river delta in south China.

Under the instruction of the State Flood Control and Drought Relief Headquarters, the Yantan Reservoir in south China's Guangxi Zhuang Autonomous Region took the lead in discharging fresh water at a speed of 1,350 cubic meters per second into the watercourses of the Pearl River Delta to alleviate the adverse impact of salt tide.

According to the emergency scheme, which was launched Tuesday, a number of reservoirs in Guangxi and its neighboring Guangdong Province will jointly discharge more than 400 million cubic meters of fresh water between January 10 and 17.

The salt tide on the river began on December 27 last year, menacing the drinking water security of hundreds of thousands of residents living in the cities of Zhuhai and Zhongshan and also Macao. The chlorine content in some drinking watercourses has kept rising abruptly.

The salt tide, the worst of its kind in the past five years, was caused by factors including less rainfall in the river's drainage area and a powerful tidal wave produced by an astronomical phenomenon that the sun, the earth and the moon will be in a line on Saturday.

The Pearl River, which originates in southwestern Yunnan Province and eventually empties into the South China Sea, is second only to the Yangtze River in surface runoff.

With a drainage area of 453,690 square kilometers, it mostly distributes in Yunnan, Guizhou, Guangxi, Guangdong, Hunan and Jiangxi provinces.

(Xinhua News Agency January 11, 2006)