The Dujiangyan () is an ancient

irrigation Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has bee ...

system in

Dujiangyan City Dujiangyan () is a county-level city of Sichuan Province, Southwest China, it is under the administration of the prefecture-level city of Chengdu. Its north-west region forms a border with southern Ngawa Tibetan and Qiang Autonomous Prefecture. ...

Sichuan Sichuan is a province in Southwestern China, occupying the Sichuan Basin and Tibetan Plateau—between the Jinsha River to the west, the Daba Mountains to the north, and the Yunnan–Guizhou Plateau to the south. Its capital city is Cheng ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

. Originally constructed around 256 BC by the State of Qin as an irrigation and flood control project, it is still in use today. The system's infrastructure develops on the Min River (Minjiang), the longest tributary of the

Yangtze The Yangtze or Yangzi ( or ) is the longest river in Eurasia and the third-longest in the world. It rises at Jari Hill in the Tanggula Mountains of the Tibetan Plateau and flows including Dam Qu River the longest source of the Yangtze, i ...

. The area is in the west part of the

Chengdu Chengdu; Sichuanese dialects, Sichuanese pronunciation: , Standard Chinese pronunciation: ; Chinese postal romanization, previously Romanization of Chinese, romanized as Chengtu. is the capital city of the Chinese province of Sichuan. With a ...

Plain, between the

Sichuan Basin The Sichuan Basin (), formerly transliterated as the Szechwan Basin, sometimes called the Red Basin, is a lowland region in southwestern China. It is surrounded by mountains on all sides and is drained by the upper Yangtze River and its tributar ...

and the

Tibetan Plateau The Tibetan Plateau, also known as the Qinghai–Tibet Plateau or Qingzang Plateau, is a vast elevated plateau located at the intersection of Central Asia, Central, South Asia, South, and East Asia. Geographically, it is located to the north of H ...

. Originally, the Min would rush down from the

Min Mountains Min Mountains or Minshan () are a mountain range in central China. It runs in the general north-south direction through northern Sichuan (the eastern part of the Ngawa Tibetan and Qiang Autonomous Prefecture and adjacent areas of Mianyang Prefec ...

and slow down abruptly after reaching the Chengdu Plain, filling the watercourse with silt, thus making the nearby areas extremely prone to floods.

King Zhao of Qin King Zhaoxiang of Qin (; 325–251 BC), also abbreviated as King Zhao of Qin (秦昭王), born Ying Ji (嬴稷), was a king of the state of Qin during the Eastern Zhou dynasty, reigning from 306 BC to 251 BC. He was the son of King Huiwen and t ...

commissioned the project, and the construction of the Dujiangyan harnessed the river using a new method of channeling and dividing the water rather than simply damming it. The water management scheme is still in use today to irrigate over of land in the region and has produced comprehensive benefits in flood control, irrigation, water transport and general water consumption. Begun over 2,250 years ago, it now irrigates 668,700 hectares of farmland. The Dujiangyan, the

Zhengguo Canal The Zhengguo Canal, Zhengguoqu or Chengkuo Canal (), named after its designer, Zheng Guo, is a large canal located in Shaanxi province, China. The canal irrigates the Guanzhong plain, north of Xi'an. Together with the Dujiangyan Irrigation Sys ...

Shaanxi Shaanxi is a Provinces of China, province in north Northwestern China. It borders the province-level divisions of Inner Mongolia to the north; Shanxi and Henan to the east; Hubei, Chongqing, and Sichuan to the south; and Gansu and Ningxia to t ...

and the

Lingqu Canal The Lingqu () is a canal in Xing'an County, near Guilin, in the northwestern corner of Guangxi, China. It connects the Xiang River (which flows north into the Yangtze) with the Li River (Guangxi), Li River (which flows south into the Gui ...

Guangxi Guangxi,; officially the Guangxi Zhuang Autonomous Region, is an Autonomous regions of China, autonomous region of the China, People's Republic of China, located in South China and bordering Vietnam (Hà Giang Province, Hà Giang, Cao Bằn ...

are collectively known as the "three great hydraulic engineering projects of the Qin". Dujiangyan Irrigation System was inscribed on the

World Heritage List World Heritage Sites are landmarks and areas with legal protection under an international treaty administered by UNESCO for having cultural, historical, or scientific significance. The sites are judged to contain "cultural and natural heritag ...

in 2000. It has also been declared a State Priority Protected Site, among the first batch of National Scenic Areas and Historical Sites, and a National ISO14000 Demonstration Area.

History

Planning

During the

Warring States period The Warring States period in history of China, Chinese history (221 BC) comprises the final two and a half centuries of the Zhou dynasty (256 BC), which were characterized by frequent warfare, bureaucratic and military reforms, and ...

, people who lived in the area of the Min River were plagued by annual flooding. Qin hydrologist Li Bing investigated the problem and discovered that the river was swelled by fast flowing spring melt-water from the local mountains that burst the banks when it reached the slow moving and heavily silted stretch below. One solution would have been to build 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, aqua ...

, but the Qin wanted to keep the waterway open for military vessels to supply troops on the frontier, so instead an artificial

levee A levee ( or ), dike (American English), dyke (British English; see American and British English spelling differences#Miscellaneous spelling differences, spelling differences), embankment, floodbank, or stop bank is an elevated ridge, natural ...

was constructed to redirect a portion of the river's flow and then to cut a channel through Mount Yulei to discharge the excess water upon the dry

Chengdu Plain The Chengdu Plain ( zh, t=成都平原, s=成都平原, p=Chéngdū Píngyuán), referred to in Sichuanese as the Western Sichuan Plain ( zh, s=川西坝子, first=t; Sichuanese Pinyin: ''Cuanxi Bazi''), is an alluvial plain located in the wes ...

beyond.

Construction

allocated 100,000

tael Tael ( ),"Tael" entry
at the

bamboo Bamboos are a diverse group of mostly evergreen perennial plant, perennial flowering plants making up the subfamily (biology), subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family, in th ...

filled with stones known as Zhulong held in place by wooden tripods known as Macha. The construction of a water-diversion levee resembling a fish's mouth took four years to complete. Cutting the channel proved to be a far greater problem, as the hand tools available at the time, prior to the invention of gunpowder, would have taken decades to cut through the mountain. Li Bing devised an ingenious method of using fire and water to rapidly heat and cool the rocks, causing them to crack and allowing them to be easily removed. After eight years of work, a channel wide had been gouged through the mountain.

Legacy

After the system was finished, no more floods occurred. The irrigation made

the most productive agricultural region in

for a time. The construction is also credited with giving the people of the region a laid-back attitude to life; by eliminating disaster and ensuring a regular and bountiful harvest, it left them with plenty of free time. Turmoil surrounding the conquering of Chengdu by peasant rebel leader

Zhang Xianzhong Zhang Xianzhong (張獻忠 or Chang Hsien-chung; 18 September 1606 – 2 January 1647), courtesy name Bingwu (秉吾), art name Jingxuan (敬軒), was a Chinese peasant leader who led a peasant rebellion from Yan'an wei, Shaanxi (today Yulin, ...

in 1644, and the

Ming-Qing transition The transition from Ming to Qing (or simply the Ming-Qing transition) or the Manchu conquest of China from 1618 to 1683 saw the transition between two major dynasties in Chinese history. It was a decades-long conflict between the emerging Qin ...

more generally, led to depopulation and the deterioration of the Dujiangyan irrigation system to the point where rice cultivation was set back for decades. The original Dujiangyan irrigation system was destroyed by the

1933 Diexi earthquake The 1933 Diexi earthquake occurred in Diexi, Mao County, Sichuan, Republic of China on August 25 with a moment magnitude of 7.3 and a maximum Mercalli intensity of X (''Extreme''). With up to 9,300 killed, this was the deadliest earthquake in 1 ...

. The current Dujiangyan irrigation system was rebuilt after the Diexi earthquake in 1933 by Zhang Yuan (张沅) and his sons, including Zhang Shiling (张世龄). In 2000, Dujiangyan became a

UNESCO World Heritage Site World Heritage Sites are landmarks and areas with legal protection under an treaty, international treaty administered by UNESCO for having cultural, historical, or scientific significance. The sites are judged to contain "cultural and natural ...

. Today it has become a major tourist attraction.

2008 Sichuan earthquake

On May 12, 2008, a massive earthquake struck a vast portion of west Sichuan, including the Dujiangyan area. Initial reports indicated that the Yuzui Levee was cracked but not severely damaged. Diversion of flow could still be seen as the river turns. Panorama of Inner Stream of Dujiangyan Irrigation System

Panorama of Inner Stream of Dujiangyan Irrigation System

Engineering constructions

Dujiangyan-Irrigation-System-TOUR-Map104

Irrigation head

The irrigation system consists of three main constructions that work in harmony with one another to ensure against flooding and keep the fields well supplied with water: The Yuzui or Fish Mouth Levee (

Chinese Chinese may refer to: * Something related to China * Chinese people, people identified with China, through nationality, citizenship, and/or ethnicity **Han Chinese, East Asian ethnic group native to China. **'' Zhonghua minzu'', the supra-ethnic ...

:鱼嘴), named for its conical head that is said to resemble the mouth of a fish, is the key part of the construction. It is an artificial

that divides the water into inner and outer streams. The inner stream is deep and narrow, while the outer stream is relatively shallow but wide. This special structure ensures that the inner stream carries approximately 60% of the river's flow into the irrigation system during dry season. While during flood, this amount decreases to 40% to protect the people from flooding. The outer stream drains away the rest, flushing out much of the silt and sediment. The Feishayan or Flying Sand Weir (

:飞沙堰) has a -wide opening that connects the inner and outer streams. This ensures against flooding by allowing the natural swirling flow of the water to drain out excess water from the inner to the outer stream. The swirl also drains out silt and sediment that failed to go into the outer stream. A modern reinforced

concrete Concrete is a composite material composed of aggregate bound together with a fluid cement that cures to a solid over time. It is the second-most-used substance (after water), the most–widely used building material, and the most-manufactur ...

weir A weir or low-head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the water level. Weirs are also used to control the flow of water for outlets of l ...

has replaced the original weighted bamboo baskets. The Baopingkou or Bottle-Neck Channel (

:宝瓶口), which was gouged through the mountain, is the final part of the system. The channel distributes the water to the farmlands in the Chengdu Plain, whilst the narrow entrance, that gives it its name, works as a check gate, creating the whirlpool flow that carries away the excess water over Flying Sand Fence, to ensure against flooding.

Anlan Suspension Bridge

Anlan or Couple's Bridge spans the full width of the river connecting the artificial island to both banks and is known as one of the ''Five Ancient Bridges of China''. The original Zhupu Bridge only spanned the inner stream connecting the levee to the foot of Mount Yulei. This was replaced in the

Song dynasty The Song dynasty ( ) was an Dynasties of China, imperial dynasty of China that ruled from 960 to 1279. The dynasty was founded by Emperor Taizu of Song, who usurped the throne of the Later Zhou dynasty and went on to conquer the rest of the Fiv ...

by Pingshi Bridge which burned down during the wars that marked the end of the

Ming dynasty The Ming dynasty, officially the Great Ming, was an Dynasties of China, imperial dynasty of China that ruled from 1368 to 1644, following the collapse of the Mongol Empire, Mongol-led Yuan dynasty. The Ming was the last imperial dynasty of ...

. In 1803 during the

Qing dynasty The Qing dynasty ( ), officially the Great Qing, was a Manchu-led Dynasties of China, imperial dynasty of China and an early modern empire in East Asia. The last imperial dynasty in Chinese history, the Qing dynasty was preceded by the ...

a local man named He Xiande and his wife proposed the construction of a replacement, made of wooden plates and bamboo handrails, to span both streams and this was nicknamed Couple's Bridge in their honour. This was demolished in the 1970s and replaced by a modern bridge.

Geography

Location

The Dujiangyan irrigation system is located in the western portion of the Chengdu flatlands, at the junction between the Sichuan basin and the Qinghai-Tibet plateau.

Geology

The Dujiangyan irrigation system is located at the turning point of the two topographic steps of the western plateau mountains and the

. It is the southwest extension of the

Longmen Mountains The Longmen Mountains (), also tautologically referred to in English-language publications as the Longmenshan Mountains, are a mountain range in Sichuan province in southwestern China. Geography The range runs in a roughly northeast to southwest ...

and the area through which the Longmen Mountain Fault Zone passes.

Topography and geomorphology

The Dujiangyan irrigation system is higher in the northwest and lower in the southeast. The west belongs to the southern section of Longmen Mountains, with the mountain elevation below 3000 meters. The east is Chengdu Plain, with an altitude of 720 meters.

Hydrology

The Dujiangyan irrigation system was built at the entrance of Minjiang River, with an average annual inflow of 15.082 billion cubic meters. There are two hydrological stations in the upper reaches of the Minjiang River. One is the

Zipingpu Dam Zipingpu Dam (紫坪铺水利枢纽) is an embankment dam on the Min River near the city of Dujiangyan, Sichuan Province in southwest China. It consists of four generators with a total generating capacity of 760 MW. Construction began in 2001 ...

at the mouth of the main stream. The water catchment area of the control survey is 22664 square kilometers, accounting for 98.38% of the total water catchment area of the upper reaches of the Minjiang River. The other is Yangliuping Dam at the outlet of Baisha River, with a controlled catchment area of 363 square kilometers, accounting for 1.58% of the total catchment area. There is a catchment area of 10 square kilometers from Estuary of Baisha River to Dujiangyan irrigation system, accounting for 0.04% of the total catchment area.

Temple sites

Two Kings Temple

Erwang or Two Kings Temple is on the bank of the river at the foot of Mount Yulei. The original Wangdi Temple built in memory of an ancient Shu king was moved, so locals renamed the temple here. The 10,072 m²

wooden complex conforms to the traditional standard of temple design except that it does not follow a north–south axis. The main hall, which contains a modern statue of Li Bing, opens up onto a courtyard facing an opera stage. On Li Bing's traditional birthday, 24th day of the 7th month of the lunar calendar, local operas were performed for the public, and on

Tomb Sweeping Day The Qingming Festival or Ching Ming Festival, also known as Tomb-Sweeping Day in English (sometimes also called Chinese Memorial Day, Ancestors' Day, the Clear Brightness Festival, or the Pure Brightness Festival), is a traditional Chines ...

a Water Throwing Festival is held. The rear hall contains a modern statue of the god

Erlang Shen Erlang Shen, or simply Erlang, is a god in Chinese folk religion and Daoism, associated with water (flood control), justice, warriorhood, hunting, and demon subdual. He is commonly depicted as a young man with a third, truth-seeing eye in the mi ...

. Because it would be a problem if a family had no offspring in Chinese feudal society, locals regarded this Erlang as Li Bing's son. Guanlantin Pavilion stands above the complex and is inscribed with wise words from Li Bing such as, ''When the river flows in zigzags, cut a straight channel; when the riverbed is wide and shallow, dig it deeper.''

Dragon-Taming Temple

Fulongguan or Dragon-Taming Temple in Lidui Park was founded in the third century in honour of

Fan Changsheng Fan Changsheng ( Fàn Chángshēng) (died 318) was a Taoist priest and leader who was instrumental in the establishment of the Cheng-Han state during the Sixteen Kingdoms era in China. He led a Taoist community of over one thousand families on Moun ...

. Following Li Bing's death a hall was established here in his honour and the temple was renamed to commemorate the dragon fighting legends that surrounded him. It is here that

, the legendary son of Li Bing, is said to have chained the dragon that he and his seven sworn brothers had captured in an ambush at the River God Temple when it came to collect a human sacrifice. This action is said to have protected the region from floods ever since. During the East Han dynasty a statue of Li Bing was placed in the river to monitor the water flow, with the level rising above his shoulders to indicate flood and falling beneath his calves to indicate drought. Recovered from the river in 1974 and placed on display in the main hall, this is the oldest known stone statue of a human in China.

References

{{authority control AAAAA-rated tourist attractions Canals in China Chinese architectural history Chinese inventions Irrigation in China Irrigation projects Major National Historical and Cultural Sites in Sichuan National parks of China Qin (state) Tourist attractions in Chengdu World Heritage Sites in China Qin dynasty architecture he:הר צ'ינגצ'נג ומערכת ההשקיה של דוג'יאנגין#מערכת ההשקיה של דוּגְ'יָאנְגְיֵן