Thursday, August 25, 2011

Dams gone wrong: Is danger lurking in China’s dams?

Probe International's recently translated an article by Southern Weekend
(Nanfang zhoumo) on July 07, 2011. Southern Weekend is one of China's
preeminent investigative news agencies. In this article, they liken
China's dams to "ticking time bombs," beset by disaster, flaws, poor
construction, neglect, and fraud.

The original article was published on July 7, 2011:

Dams gone wrong: Is danger lurking in China�s dams?
August 24, 2011
By Lu Zongshu and Shen Nianzu

China has built over 87,000 hydro dams, more than any other country in
the world. Hydro dams and reservoirs perform many functions including
flood control, power generation, irrigation, and water supply and so
forth, but the issue of dam safety has always been treated as a
sensitive subject. Now, incidents at a number of dams and reservoirs
have cast doubt on the quality of these projects, but they are rarely
reported to the general public.

Shocking dam incidents

A nation-wide survey focusing on key dams and reservoirs in China will
be carried out, but the authorities have yet to disclose details. Given
the recent debates about whether dams and reservoirs have caused
droughts and floods, this idea is interesting and significant.

The announcement that the survey will be carried out was made at the
2011 Annual Conference of the Chinese National Committee on Large Dams
(CNCLD). Zhang Rushi, Deputy Director of the Work Safety Department of
the Ministry of Water Resources made the announcement and stated that,
through surveys and field investigations, the study aims to discover the
true situation with China's hydro dams.

On June 18, 2011, about three hundred leading experts in China's water
resources and hydropower industry gathered in Yichang, Hubei Province,
to attend the Annual Conference held by the CNCLD. The participants
included Wang Shucheng, former Minister of Water Resources and current
chairman of the CNCLD, and Lu Youmei, member of the Chinese Academy of
Engineering and former general manager of the Three Gorges Corporation.

"Dam safety" was among the most oft-mentioned words by the experts at
the conference. "Safety comes first," insisted Wang Shucheng. "Dam
safety should always be put first in the construction of hydro dams. We
should not be the people who are condemned by history, feeling ashamed
and regretful for what we have done to the motherland and to our people."

During his presentation at the CNCLD meeting, Zhou Jianping, chief
engineer of the China Hydropower Engineering Consulting Group, showed
the audience about ten photos of different dam accidents. These images,
never before disclosed, shocked the general audience, but especially
reporters from the media. Afterwards, reporters from Southern Weekend
did a great deal of research, but could find little detail about the
incidents on the Internet.

The first picture was about the Ertan Hydropower Station built on the
Yalong River (a tributary of the Yangtze, in Sichuan Province), whose
spillway tunnel was completely destroyed by flood waters. For the
general, non-technical audience, like us, it was especially difficult to
imagine how such a solid reinforced concrete structure could be washed
away and broken into pieces like a heap of loose sand. As the speaker,
Zhou Jianping said, it was very fortunate that they found the problem in
time and fixed it, or the Ertan dam would have been seriously threatened.

Another photo caused a buzz in the audience: the flood spillway of the
Sanbanxi dam in Jinping County, in southeast Guizhou Province, was
totally destroyed on July 26, 2007, after only 13 hours of operation.
Apparently, there was a problem with the quality of construction,
causing as much as 13,000 cubic meters of concrete and rock to wash
away, leaving a pit as deep as 11 meters, or the equivalent of a
three-story high building. According to Zhou Jianping, the consequences
could have been disastrous if floods had occurred at the same time and
the operators were unable to close the sluice gates.

At the Jinghong dam, built on the Lancang-Mekong River and lauded as one
of the most important hydro dams in Yunnan Province, the flood discharge
channel twice suffered serious damage from floods, once in 2008 and then
again in 2009. As the picture illustrated, the channel was torn open
like a big mouth as if blown up by a bomb, with steel bars hanging
around like withered plants.

Another of the incidents resulted in casualties: as Zhou Jianping
explained, the road leading to the site of the Jishixia dam on the
Yellow River in Qinghai Province suddenly collapsed one evening as a
result of silt being discharged. Drivers of two vehicles unknowingly
drove along the damaged road, crashing into the Yellow River. At least
eight people are still missing.

In his speech to the conference, Zhou Jianping concluded that the
accidents were the result of low standards, including inadequately
prepared surveys, unscientific design and construction plans, mismanaged
construction, absence of quality control and supervision, and even fraud
in building materials. All of these factors have contributed to the poor
quality of dam projects and compromised the safety of dams.

Regulations lag behind reality

Pan Jiazheng, one of the founders of China's hydropower industry and an
expert in water resources, often warned that any errors and oversights
in dam design and construction would compromise the quality of the
projects. Dealing with the aftermath of these problems would be more
costly, he said, including the loss of innocent lives.

For example, on August 27, 1993, the dyke in the Gouhou reservoir in
Qinghai Province burst, killing 288 people (the dam's height is 71 m).
Back in August 1975, two large reservoirs, Banqiao and Shimantan,
together with two other medium reservoirs and 58 small reservoirs in the
Zhumadian area of Henan Province, collapsed one after another, in just a
few hours.[i] Ten counties and towns in Zhumadian were flooded by as
much as 5.7 billion cubic meters of water, and 26,000 people died as a

Dams under construction are also encountering problems. The Xiluodu
hydropower station, for instance, China's second largest hydropower dam
on the Jinsha River, has been experiencing construction problems going
back to 2010. Engineers and workers on the construction site found that,
after pouring hundreds of cubic meters of concrete, the template was
incorrectly positioned. A person familiar with the situation said that
the financial cost of the mistake was not big, but the time lost to
removing the concrete (which had already solidified), and re-pouring it,
seriously affected the project's schedule.

According to a 2009 report by the Sinohydro Engineering Bureau 3 Company
Limited, entitled, "A summary report on technological research dealing
with problems at hydraulic structures," problems have occurred at a
number of dams: cracks were discovered in section 6 of the Danjiangkou
dam (on the Han River, a tributary of the Yangtze [ii]; leaks occurred
in the Shiban hydrodam structure in Fuling (formerly in Sichuan Province
and currently a District of Chongqing Municipality[iii]; leaks also
occurred in the Tianshengqiao tunnel of the Erlangba hydrodam in Shaanxi
Province; and concrete defects have been found in the shiplock of the
Three Gorges dam project. In fact, according to a 2006 survey of Three
Gorges, 733 cracks, with a total length of 4,688 meters, on both the
eastbound and westbound channels of the shiplock, have leaked water.
But, the survey said, these cracks were subsequently repaired in order
to meet the design requirements "through professional treatment."

As the Chinese media put it ironically, China's hydropower construction
has entered a "Great Leap Forward," with the giant power companies
divvying up watersheds and rushing to construct hydropower projects.
According to recent news, the Three Gorges Group is accelerating its
construction of four giant hydro dams on the Jinsha River that will
generate twice the power output of Three Gorges if all the projects go
into operation.

This situation worries the older generation of hydropower experts. As
Wang Shucheng explained, it used to take years to prepare surveys and
investigations before construction of a dam began. Now the job is
usually done in a hurry, he added. Especially worrying, many large
projects are being built in southwest China where the geological
conditions are complicated and the area is seismically active. For that
reason, it will be particularly dangerous to build dams without a sound
plan and without implementing it stringently, Mr. Wang warned.

According to information provided by CNCLD, as of 2009, China had built
and was constructing 5,443 hydro dams with a height greater than 30
meters. Thirteen of those are higher than 200 meters. But the "Dam
Safety Regulations," which are meant to govern dam construction in
China, were issued in 1991 and apply only to dams up to a maximum height
of 200 meters.

"The problem is that the regulations lag behind the reality," Zhang
Rushi, Deputy Director of the Work Safety Department of the Ministry of
Water Resources told the 2011 CNCLD conference. Because the regulations
are inadequate when it comes to meeting current needs for dam safety, it
is a high priority that they be revised.

China's poorly constructed dams and those that have become dangerous
after years of neglect are like ticking time bombs. According to an
earlier report about dam incidents entitled "Statistics and Preliminary
Analysis of Incidents with Dams and Reservoirs in China," more than half
of China's reservoirs were built between 1950 and 1980, most under
conditions known as "building while investigating, and building while
designing." These circumstances led to low standards and poor quality
construction. To make matters worse, most are today in a dangerous state
of ill-repair after decades of operation (see charts below).

Note: The data in Chart 2 comes from statistics gathered between 1954
and 2003. Dams in Chongqing Municipality are included in Sichuan
Province's statistics because Chongqing Municipality did not exist at
the time, but came under the jurisdiction of Sichuan Province. Source:
"Statistics and Preliminary Analysis of Incidents with Dams and
Reservoirs in China," by He Xiaoyan, Wang Zhaoyin and Huang Jinchi, and
Ding Liuqian. (Charts by Li Bogen).

Based on the statistics provided by He Xiaoyan (one of the authors of
"Statistics and Preliminary Analysis of Incidents with Dams and
Reservoirs in China," who is now working in the Department of
Flood-Control and Disaster Reduction of the China Institute for Water
Resources and Hydropower Research), there were a total of 3,481 dam
collapse incidents in the 50 years from 1954 to 2003 (excluding Taiwan).
He Xiaoyan points out that:

"Inadequate flood-discharging capacity and problems with project quality
were the main causes of dam failure and collapse; 96.4% of the
reservoirs where these incidents occurred were small ones."

China has become increasingly concerned about dam safety and has
repaired and reinforced 9,225 poorly constructed and dangerous
reservoirs in the past ten years. In the last three years alone, 64.5
billion yuan RMB has been spent. In the next five years, 41,000
reservoirs are set to be repaired, requiring large financial commitments
from state budgets.

As Zhang Rushi said, the preparatory work for the nationwide survey of
big dams and reservoirs has already been done. The investigation will
now be carried out by the Ministry of Water Resources, together with the
State Administration of Work Safety, the State Electricity Regulatory
Commission, and the Ministry of Agriculture.

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