Chinese geological experts have reassured the public that water
filling of the Three Gorges reservoir will be safe and reliable
amid fears of possible geological disasters such as catastrophic
earthquakes.
"The 135-meter-deep reservoir won't cause major geological
disasters that would endanger the dam's safety, hamper navigation
or incur great losses," said Liu Guangrun, chief scientist of
geological disasters prevention at the Three Gorges.
The reservoir's sluice gate was closed on Sunday and the water
level is expected to rapidly rise to 135 meters within two
weeks.
"China has established its largest-ever system to prevent and
control probable geological disasters at Three Gorges area," said
Liu, who is also an academician of the Chinese Academy of
Engineering.
Liu said the sites where minor geological disasters had been
discovered or were at risk were closely monitored or
controlled.
Geological disasters like landslides, collapses and muck-rock flows
were very common before the construction of the Three Gorges
Project, sparking fears about possible calamities after the water
storage.
"We are capable of handling geological disasters, given our current
engineering technologies," Liu said.
Lin Wenliang, a senior official with the Three Gorges Project
Bureau of the Yangtze River Water Resources Committee, agreed that
the filling of the Three Gorges reservoir was unlikely to lead to
catastrophic earthquakes.
"There is a small possibility the reservoir causing earthquakes
because it is belt-shaped, extending 660 km, and in such a big
area, the per unit pressure caused by 35 billion cubic meters of
water will be insignificant," Lin explained.
Moreover, Lin went on, the Three Gorges Project was built on a
complete solid granite structure where no rupture had been recorded
for thousands of years, so even if there was an earthquake caused
by the reservoir, the intensity would be no bigger than six degrees
on the Richter scale, the strongest recorded earthquake in the
Three Gorges Area.
"The nearest previous earthquake rupture zone is 39 km from the
site of the Three Gorges Dam, but the Three Gorges Project is
designed to withstand earthquakes measuring seven degrees on the
Richter scale," Lin added.
During the past two years, China has invested four billion yuan
(US$482 million) in the prevention and control project of
geological disasters in the Three Gorges area.
A
geological disasters monitoring and early warning system had also
been set up in the Three Gorges reservoir area, said Hu Xuqing, an
official in charge of the geological calamities prevention office
of the reservoir area, Chongqing, western China's biggest
municipality.
"We have launched 24-hour monitoring of the geological situation in
the reservoir area and will issue early warnings if necessary," Hu
said.
Advanced technologies like satellite remote sensing had also been
used in monitoring the geological situation in the reservoir
area.
The construction of the Three Gorges Project, the world's biggest
hydro-electric project, began in 1993 and is expected to be
completed in 2009.
(Xinhua News Agency June 3, 2003)