Is Xiaowan (China)
the highest arch dam in the world?
Prof. Dr. Nguyen Van Le (Water Resources University) has just sent us a brief note that as the Xinhua News Agency, the Xiaowan Dam (Yunnan Province, China) on the Lancang River (Upstream Mekong River) was succeeded last year. The Xiaowan Dam with 292m height becomes the highest arch dam in the world, over the last “record” of the Inguri Dam (Gruzia) with 271.5m height.
Vietnam experts are doing their investigation for an arch dam (Nam Chien) with 136m height to generate power energy with 200MW capacity.
The Xinhua news file is followed:
China's Xiaowan hydroelectric power station succeeds
October 28, Xinhua News Agency
China's Xiaowan hydroelectric power station succeeds in damming river
China's top project for western development, the Xiaowan Hydroelectric
Power Station, has dammed the Lancang River a year ahead of schedule after
three years of all-out, arduous efforts.
The hydropower station, second in size in China only to the Three Gorges
Power Project, then announced to start the construction of a
292-meter-high, concrete hyperbolic arch dam, the highest of the world.
The Xiaowan Hydroelectric Power Station is an essential part of China's
strategy of transmitting electricity from resources- abundant western
areas to power-short Shanghai Municipality, Guangdong, Jiangsu and other
The hydropower station is being built on the middle reaches of the
turbulent Lancang River, the fifth longest in China. Xiaowan Station,
whose construction began in early 2002, will have six generating units
with a designed capacity of 4.2 million kilowatts.
The cost of the Xiaowan hydropower station is estimated at 32 billion yuan
(nearly 3.9 billion US dollars), the largest sum spent on a project of
this kind in Yunnan province in the past 50 years.
The first generating unit of the project is expected to go into operation
in late 2010, and the last one will be finished three years later. By
then, its annual power output will be 18.9 billion kwh, half of which will
be sent to Guangdong and other provinces in coastal areas.
The major feature of the hydropower station is a concrete hyperbolic arch
dam that towers 292 meters high, which is equivalent to the height of a
The dam, believed to be the highest dam on earth, will form a reservoir
with a storage capacity of 15 billion cubic meters after it is completed.
This is equal to the combined amount of all reservoirs in Yunnan. The
hydropower station will also perform other functions such as flood
control, irrigation, sand retention and navigation.
As the construction of Xiaowan station faces many knotty technical
problems, China launched cooperation schemes with prestigious experts from
the United States, Norway, Russia and France during the construction
China's hydroelectric experts said the establishment of the Xiaowan
station would turn the international Lancang-Mekong River into a "golden
watercourse" and benefit all countries along the river.
Lancang River, which rises in the Tanggula Mountains on the Qinghai-Tibet
Plateau, flows for a total of 4,500 kilometers from Tibet to Xishuang
Banna in Yunnan Province, joins the Mekong River, and then flows into
Laos, Myanmar, Thailand, Vietnam and other countries.
Currently, China is building six hydroelectric hydropower stations on the
middle and lower reaches of the Lancang River in addition to the Manwan
and Dachaoshan hydropower stations. The combined installed capacity of the
eight power stations will amount to 15.55 million kw, upon their
A Quick Guide to the World of Dams
· The World Commission on Dams estimated that there are as many as 48,000 dams over 15m high worldwide. About half of these are in China.
· The International Commission on Large Dams (ICOLD) defines a large dam as being over 15 m high. The definition also includes dams between 5-15 m high with a reservoir exceeding 3 million cubic meters.
· Dam building peaked in the '70s and declined globally after that. Nevertheless, dam building in China, Turkey, Brazil and India still continues on a large scale.
· On average one new dam is build every day and the average construction time is 4 years.
· The highest dam in the world is the Rogun Dam in Tajikistan which is 335 m high. The highest dam currently under construction is the 292 m high Xiaowan Dam on the Mekong in China which, when it is completed, will be the highest Arch dam in the world.
· Itaipu, shared between Brazil and Paraguay, has the highest installed capacity at the moment, with 12,600 MW. When the Three Gorges Dam is completed it will take over as the dam with the largest capacity, reaching 18,200 MW.
· The installation of 1 MW of hydropower capacity costs about $1 million.
· About 1500 dams are currently under construction worldwide.
· China has a total of 88 dams under construction and at least 36 more dams planned; Turkey has 60 dams under construction and 50 more planned.
· China and Turkey, together with Iran and Japan account for 67% of the total number of dams under construction worldwide in 2003.
· Hydropower currently provides 19% of the world's total electricity supply, and is used in over 150 countries with 24 of these countries depending on it for 90% of their supply.
· 30-40% of the 271 million hectares of agricultural land irrigated worldwide rely on dams.
· 60% of the world's 227 largest rivers are severely fragmented by dams, diversions, and canals - leading to the degradation of ecosystems.
· The World Commission on Dams (WCD) estimated that the annual expenditure on large dams during the 1990s was between $32 and $46 billion. Of the $22-31 billion invested in dams each year in developing countries, about four-fifths was financed by the public sector. The WCD calculated that throughout the twentieth century some $2 trillion had been spent on dams.
Reply: Thank you, Prof. Nguyen Van Le, for your information and do hope your further collaboration.Website Edit. Board