Zhuhai City of south China's Guangdong Province, has been activating an emergency system in response to a crisis in water supply caused by advancing of a grave salt tide in the river's estuary.

Under the emergency system, an economized use of water is compulsory. And all water consuming facilities such as swimming pools, sprinkling landscapes in residential quarters, and services including car washing businesses and bath centers are temporarily suspended from water supplies, said Zhong Huiming, deputy director of the Water Affairs Bureau of Zhuhai, the nearest Chinese mainland city to Macao.

"We will guarantee a normal use of water for residents in Zhuhai and Macao at all costs," said Zhong.

The salt tide on the river began on Tuesday, threatening drinking water security of hundreds of thousands of residents living in Zhuhai and Macao. The chlorine content in drinking water sources in Zhuhai has kept rising abruptly.

But the adverse impact of the salt tide on drinking water in other cities in the densely populated Pearl River Delta, such as Zhongshan, Guangzhou, Dongguan, Shenzhen and Hong Kong, will be limited.

The salt tide, the worst of the 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.

Specialists with Guangdong Provincial Astronomers Society predict that the salt tide in the Pearl River will stay for some time because of the above mentioned factors.

Guangzhou, the provincial capital of Guangdong, and Zhongshan City, also in Guangdong, are joining Zhuhai to get well prepared for combating the salt tide.

In the meantime, Guangdong Province and Zhuhai City have been organizing experts to study details about diverting water from Beijiang, one of the Pearl River's tributaries, to drive back salt tide.

It is expected that the actual water diversion will begin mid-January next year.

The Pearl River, which originates in the Maxiong Mountain inside Quqing City, southwest China's Yunnan Province, runs southeastwardly and eventually empties itself into the South China Sea, is placed the second only after the Yangtze River, the country's longest, by surface runoff.

(Xinhua News Agency January 1, 2006)