A 10-day silt clearance campaign for the middle and lower reaches
of the Yellow River is set to begin at 8:30 this morning at
Xiaolangdi
Reservoir in Central China's Henan Province. The campaign aims
to clear long-deposited silt in Henan, Shanxi and Shandong
provinces, with powerful water flow sent out from the Xiaolangdi
Reservoir.
The water flow will blast along the river at a controlled speed of
2,600 cubic meters per second, and the whole process is expected to
last 10 days, said Li Guoying, director of the Yellow River Water
Conservancy Committee.
Li
said the planned trial is the world's largest silt-clearing
campaign to date, and the committee is optimistic about the
results.
The middle and lower reaches of the Yellow River have long been
plagued by expanding silt deposits. The high river banks
established to resist silt in many places have surpassed the
altitude of urban regions, which is a great danger to local
populations.
Li
said the committee expects the powerful water flow to flush away
much of riverbed silt and reduce the pressure caused by silt
expansion.
Though well prepared, Li said they were still not sure if the
2,600-cubic-meters-per-second volume of water is enough to rush the
long-deposited silt away. The committee will send water in various
intensities over the 10 days, and monitor the clearance conditions
closely throughout the three provinces involved.
Li
believes this trial will collect useful data for the committee's
future silt-clearing efforts.
On
the down side, the artificial powerful water flow will cause some
small-scale flooding in the provinces through which it passes,
especially along some narrow riverways.
The water conservancy departments in the three provinces have been
alerted about a possible deluge. They were all ordered to monitor
the water flow around the clock, and have prepared enough rescue
materials for the worst case scenario.
The Xiaolangdi Reservoir is one of the most important water
management tools along the Yellow River, China's second largest
river. Besides providing industrial and agricultural water for
nearby cities, the reservoir also helps adjust water volume flowing
to the lower reaches in different seasons.
Construction on the reservoir began on August 20, 1998, and it was
put into operation in October. The total expenditure was 126
million yuan (US$15 million).
The water conservancy committee sources said the successful
operation of the water reservoir so far has proved it can be used
effectively for the silt-clearing test.
With data gathered in this trial, the sources said, they will
launch more water-clearing campaigns along the lower reaches. The
precondition is that such efforts do not endanger the cities along
the river.
(China
Daily July 4, 2002)