Temblor Throws Shadow on Big Dam Ambitions

Antoaneta Bezlova
Wednesday, June 25, 2008

Originally published in the Inter Press Service News Agency

DUJIANGYAN, Jun 25 (IPS) - China's deadly earthquake last month
appears to have shifted more than just tectonic plates in the
country's picturesque Sichuan province. The May 12 temblor has given a
boost to China's green lobby that has been calling for a review of
Beijing's zealous dam-building programme and may tilt the balance of
public opinion in favour of such appeals.

When the quake struck, it came in an area famous for ancient
hydrological works. Sichuan is the homeland of Da Yu, the legendary
Chinese emperor who won his right to the throne in 21st century BC by
controlling the floods. Instead of building dikes as others before him
did, Yu dredged out river channels to release the torrential waters.
He then directed the water to irrigate distant farm lands.

Twenty centuries later, Yu's flood controlling technique was
immortalised in the hydraulic project of Dujiangyan. The ancient
system -- operational now for the past 2,000 years -- has made the
city of the same name a magnet for tourists and has won it recognition
as a UNESCO World Heritage Site.

While the city of Dujiangyan was almost entirely destroyed by the
magnitude eight earthquake, the old hydraulic system located only 10
km from the epicentre, survived the temblor with little damage. The
same cannot be said about the cluster of 6,000 reservoirs and dams
that local experts estimate have been built on the rivers of Sichuan.

"Such a strong earthquake would have an enormous influence on the dams
in the whole area," says David Simpson, a U.S. seismologist with the
Incorporated Research Institutions for Seismology (IRIS). "You are
certain to have concerns if you build many dams in mountainous areas
as is the case in Sichuan".

In the wake of the quake, which has claimed nearly 70,000 lives, the
rush and struggle to assess the damage done to Sichuan's hydropower
works were featured less prominently by the media than the frenzy of
rescue operations. But as provincial authorities brace for the surge
of seasonal floods, the danger of dams bursting and creating a much
bigger havoc than the earthquake has prompted Chinese experts and
activists to raise their voices.

An open letter issued by a group of 40 academics and environmentalists
on Jun. 19 warned of more devastation if environmental and geological
risks of damaged dams are disregarded. "The quake has highlighted the
urgency to make a thorough investigation of damage to the dams, which
would embrace another severe test of imminent floods,'' the petition

An official survey by the Ministry of Water Resources last month
revealed that 2,380 reservoirs and dams all over the country sustained
damage from the quake. Some 69 were assessed to be on the verge of
collapse. But experts say this is only the tip of the iceberg.

Modern China did not follow the path of its ancient sages in using
rivers' natural flows to control flooding and irrigate the land. The
late communist chairman Mao Zedong decreed that China's new socialist
man must conquer nature. In less than 60 years since the founding of
communist China, the country managed to build some 87,000 reservoirs
and dams.

Over 20,000 of these are significantly high to be considered large
dams. Whether in terms of numbers or grandness of dam works, China now
is the world's ultimate leader. It is home to the Three Gorges Dam --
a mammoth hydroelectric power project on the Yangtze River -- which in
the course of construction displaced more than one million people.

The country's leadership though is not stopping here. There are more
than 30 large dams on the drawing boards of Chinese engineers awaiting
approval and completion as the country scrambles to feed its
energy-starved economy.

Initial official statements after the quake indicated little waver
from Beijing's determination to press on with intensive hydropower
development in the area.

"There will be risk assessments of future projects in China's
southwest but I don't think the quake would lead to great changes in
current plans," Liu Ning, chief engineer with the Ministry of Water
Resources, told the press soon after the earthquake.

Having harnessed major rivers and tributaries in the country's central
and eastern parts, the attention of Chinese planners is now focused on
developing the abundant water resources of western and southern
provinces. But that water cache comes with a snag -¨C the southwestern
part of China is one of the most earthquake-prone zones in the

Three major fault lines traverse Sichuan, making it geologically
unstable. Nevertheless many big dams had already been built in the
area, such as those on the Min, Dadu, Jinsha and Yalu River. The Min
river, a tributary of the Yangtze that runs right through the
earthquake zone, has not less than 29 reservoirs and dams.

What is more, Zipingpu -¨C Min river's largest dam -- sits only 5.5 km
from the epicentre of the earthquake. Fan Xiao, a geologist based in
Sichuan, believes the construction of Zipingpu has contributed to the
severity of the latest earthquake.

"There has never been such a strong earthquake in this area before,"
Fan says. "Our records show four earthquakes in the past of magnitude
above six but never one stronger than this latest one. Zipingpu is the
biggest dam on the Longmenshan fault line and it was filled sometime
ago - in the end of 2006. We need to investigate the possibility that
the dam was among the triggers of the quake."

Sichuan Seismological Bureau, which from the very beginning opposed
the construction of the dam because of its proximity to the
Longmenshan fault line, is now investigating the likelihood that the
dam could have exacerbated the severity of the tremor. "We hope the
results of the investigation would be made public," says Fan.

Four major earthquakes in the past are acknowledged to have been
triggered by dams in their vicinities -¨C in Koyna, India (1967),
Kremasta, Greece (1965), in Kariba, Zimbabwe-Zambia (1961) and in
Xinfengjiang, China (1962). China's quake measured 6.1 and damaged the
Xinfengjiang power station in Guangdong to such extent that it led to
its closure.

While Zipingpu in Sichuan was built to the highest quake-resistant
standards, many other Chinese dams, particularly those designed and
constructed during the Great Leap Forward (1958-1961) and in the 1960s
are not. They are often referred to by experts here as "time bombs". A
history of China's half-century of dam building, compiled by academic
Pan Jiazheng, estimates there are 30,000 of these poorly built and
obsolete structures all over the country.

The May 12 tremor caused the quake-proof Zipingpu Dam to sustain
severe cracks and fractures on the sides but the damage done to other
older and less quake-resistant dams is anybody's guess.

The open letter issued by China's green lobby appeals not just for
thorough investigation into the quake damage but also for risk
assessments of all hydropower projects planned for earthquake-prone
Sichuan and Yunnan provinces. A series of 13 dams -- many of them
taller than the 150 metre- high Zipingpu -- are projected to be built
on the Nu River, in proximity to another major fault line near China's
border with Burma and Laos.