The Banqiao Reservoir Dam () is a

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use ...

on the River Ru (), a tributary of the Hong River in

Zhumadian Zhumadian (; postal: Chumatien) is a prefecture-level city in southern Henan province, China. It borders Xinyang to the south, Nanyang to the west, Pingdingshan to the northwest, Luohe to the north, Zhoukou to the northeast, and the province of An ...

City,

Henan Henan (; or ; ; alternatively Honan) is a landlocked province of China, in the central part of the country. Henan is often referred to as Zhongyuan or Zhongzhou (), which literally means "central plain" or "midland", although the name is al ...

province, China. The Banqiao dam and Shimantan Reservoir Dam () are among 62

s in

that failed catastrophically in 1975 during Typhoon Nina. The dam was subsequently rebuilt.

History

Construction

Construction of the Banqiao dam began in April 1951 on the Ru River with the help of Soviet consultants as part of a project to control

flood A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrol ...

ing and provide electrical power generation. The construction was a response to severe flooding in the

Huai River The Huai River (), formerly romanized as the Hwai, is a major river in China. It is located about midway between the Yellow River and Yangtze, the two longest rivers and largest drainage basins in China, and like them runs from west to ea ...

Basin in 1949 and 1950. The dam was completed in . Because of the absence of hydrology data, the design standard was lower than usual. After the 1954

great flood, the upstream reservoirs including Banqiao were extended, constructed, and consolidated. Banqiao Dam was increased in height by . The dam crest level was above sea level and the crest level of the wave protection wall was above sea level. The total capacity of the reservoir was 492 million m³ (398,000 acre feet), with 375 million m³ (304,000 acre feet) reserved for

storage. The dam was made of

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay par ...

and was high. The maximum discharge of the reservoir was per second. Cracks in the

and

sluice gates Sluice ( ) is a word for a channel controlled at its head by a movable gate which is called a sluice gate. A sluice gate is traditionally a wood or metal barrier sliding in grooves that are set in the sides of the waterway and can be considered ...

appeared after completion due to construction and engineering errors. They were repaired with the advice from

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nation ...

engineers and the new design, dubbed ''the iron dam'', was considered unbreakable.

Whistle-blower

Chen Xing (), one of China's foremost

hydrologist Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is calle ...

s, was involved in the design of the dam but he was also a vocal critic of the government's dam building policy which involved many dams in the basin. He had recommended 12

sluice gate Sluice ( ) is a word for a channel controlled at its head by a movable gate which is called a sluice gate. A sluice gate is traditionally a wood or metal barrier sliding in grooves that are set in the sides of the waterway and can be considered ...

s for the Banqiao Dam but this was criticized as being excessive and the number was reduced to five. Other dams in the project, including the Shimantan Dam, had a similar reduction of safety features and Chen was removed from the project. In 1961, after problems with the water system were revealed, Chen was brought back to help. He continued to be an outspoken critic of the system and was again removed from the project.

1975 Banqiao Dam failure

In August 1975, the Banqiao dam collapsed, creating the third-largest flood in history which affected a total population of 10.15 million and inundated around 30 cities and counties of 12,000 square kilometers (or 3 million acres), with an estimated death toll ranging from tens of thousands to 240,000.

Reconstruction

Within eleven years of the dam failure, the lower reach of the River Ru, esp.

City, experienced several more disastrous floods. After many feasibility studies, the new Banqiao Reservoir reconstruction was listed as a key national project of The Seventh Five-Year Plan of China. The project owner was

Huai River Water Resources Commission Huai River Water Resources Commission (HRWC) is a government agency of Ministry of Water Resources of the People's Republic of China. HRWC takes responsibility of water administration of the Huai River basin which covers some parts of Henan, A ...

. The construction contractor was Changjiang Gezhouba Engineering Bureau. By the end of 1986, the rebuilding project commenced. On June 5, 1993, the project was certified by the Chinese government. The reconstructed Banqiao Reservoir controls a catchment area of . The maximum reserve capacity is 675 million m³ (178 billion gallons), a capacity increase of 34% above the capacity of the failed dam. The effective storage is 256 million m³ (67.6 billion gallons) and the corresponding normal high water level is above sea level. The flood control storage is 457 million m³ (121 billion gallons). The dam is made of

and is long and high. The dam crest level is above sea level. The maximum discharge of the reservoir is per second.

Legacy

After the disaster of the Banqiao dam failure, the Chinese government became very focused on surveillance, repair, and consolidation of reservoir dams. China has 87,000 reservoirs across the country; most of which were built in the 1950s–1970s using low construction standards. Most of these reservoirs are in serious disrepair, posing challenges to the prevention and control of flood-triggered geological disasters in areas with a population of 130 million or more. China's medium and small rivers are considered to be the Achilles' heel in the country's river control systems. According to a report from 2010, by the Ministry of Water Resources, China has invested () since the

1998 Yangtze River floods The 1998 China floods (1998年中国洪水) lasted from middle of June to the beginning of September 1998 in China at the Yangtze RiverChinanews.com.cn.Chinanews.com.cn" ''98年特大洪水.'' Retrieved on 2009-08-01. as well as the Nen River, Son ...

in repairing and consolidating the country's 9,197 degraded reservoirs, of which 2,397 are large or medium-sized, and 6,800 are key small reservoirs.

References

External links

Human Rights Watch report Excerpt from ''Silenced Rivers: The Ecology and Politics of Large Dams'', by Patrick McCullyA Procedure for Estimating Loss of Life Caused by Dam Failure
(PDF)
Flood and Drought in the History, Hydrology Department of Henan (Simplified Chinese)
([https://translate.googleusercontent.com/translate_c?depth=1&nv=1&pto=aue&rurl=translate.google.com&sl=auto&sp=nmt4&tl=en&u=http://news.163.com/41124/6/15VFF9QE00011249.html&usg=ALkJrhhroQX_mQrmLJGgESwogWxTMB20oQ Translated])
Typhoon Nina TrackThe River Dragon Has Come!: The Three Gorges Dam and the Fate of China's Yangtze River and Its Peopletranscript:four-episode documentary film: Remember the Flood in August 1975
{{Portal bar, China, Engineering, Environment Buildings and structures in Henan Dams in China Dams completed in 1993