The silt deposits in the lower reaches of the Yellow River still pose a threat to the lives and property of people living in the river valley, according to experts.
The conclusion appeared in a report published Sunday about China's first ever experiment to readjust the water and silt in the country's second-longest river.
The river's principal problem has always been the silt deposits caused by exceptionally high levels of sediment.
The river bed in the lower reaches rose to a level above that of the surrounding fields, leading to the Yellow River being described as a "hanging river."
But things have got even worse. A substantial amount of sediment left behind has contributed to the silting of the river channel. This has significantly raised the river bed and built up another "hanging river" on the base of the first one.
The 17-day experiment conducted last July and August showed that the speed of the current flow in the lower reaches of the river is less than 3,000 cubic meters per second.
In the 1980s and 1990s, the water flow in the river's lower reaches was 5,000 cubic meters per second.
The second "hanging river" extends about 900 kilometers from Jiahetan hydrological station in the city of Kaifeng, in Central China's Henan Province, to the river's estuary in the Bohai Sea.
In one 80-kilometre section, considered the most seriously affected part, the river bed is four meters higher than the surrounding beach.
A China Central Television news report quoted Yellow River Water Conservation Committee sources as saying that the river bed in the lower reaches is growing higher and higher, greatly increasing the risk of flooding and the breaching of dykes. The consequences are potentially disastrous, the sources said.
Experts attributed the phenomenon to chronic dry weather and the rising amount of industrial and agricultural intake from the river.
(China Daily January 20, 2003)
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