For the first time in 12 years, the sluice gates at Wangjiaba on the Huaihe River, one of China's major rivers, were opened early Thursday morning to divert floodwater generated by heavy rainfall in the river valleys.

The decision was made by the State Flood Control and Drought Relief Headquarters at 6 p.m. Wednesday, when the water level at Wangjiaba, in Funan County of east China's Anhui Province, reached the warning line of 28.66 meters.

The Huaihe River runs about 1,000 km between the Yellow and Yangtze rivers, through Henan, Anhui, Jiangsu and Shandong provinces. Its drainage areas cover some 270,000 sq. km. and is home to a population of 165 million.

With an average of over 600 residents per square kilometer, the Huaihe River valleys boast the highest population density of any Chinese river.

With a history rich in ancient culture, the Huaihe River valleys were reduced to a disaster area in the 12th century.

After the founding of New China in 1949, Chairman Mao Zedong proposed that the river be harnessed as an energy source, and the Huaihe River thus became China's first river to undergo comprehensive and systematic realignment under the Chinese government.

The most recent flooding occurred in 1991, claiming 500 lives and generating 30 billion yuan (US$3.6 billion) in property losses.

The Huaihe River valleys play an important role in China's economic and social development by contributing one-sixth of the country's grain, one-fourth of its cotton and edible oil, and one-eighth of the national coal output.

Four major railway lines, namely the Beijing-Guangzhou, the Beijing-Kowloon, the Beijing-Shanghai and the Lianyungang-Lanzhourun through the Huanhe River valleys.

Since the 1950s, more than 20 emergency floodwater storage reservoirs, with a combined storage capacity of 28 billion cubic meters of water, have been built in lakes and depressions along the middle reaches of the river.

The Mengwa floodwater storage project, designated as the storage area this time, was one of the first to be built for this purpose, and the sluice gates at Wangjiaba divert floodwaters to the Mengwa area.

During the 38 years following the dam's completion in 1953, the Wangjiaba sluice gates had been opened 12 times in ten years. In 1991, the sluice gates were opened twice to divert floodwaters, submerging the Mengwa area for the entire summer and autumn.

It is estimated that some 12,000 hectares of farmland will be submerged this time, and, in preparation, all 150,000 residents of the Mengwa area have been evacuated together with some fertilizer and poisonous pesticides.

(Xinhua News Agency July 3, 2003)