Man Vs Nature: Dujiangyan Irrigation System Case Study

Subject: Environment
Pages: 10
Words: 2826
Reading time:
10 min
Study level: PhD

Statement of the case

Few people even in the contemporary modern world enjoying the benefits of technology and scientific innovations have been able to surpass achievements by Shu’s Governor Li Bing. People of Shu State had suffered for many years from flooding along the Minjiang River. Minjiang is one of the tributaries of the Yangtze River in China. It was sheer determination and foresight that led the Governor and King Zhao to turn the disaster of flooding into an economic resource and a wonder that is still subject to scientific studies even to date, more than 2000 years later. Using mere bamboo sticks and natural stones, Li Bing and Zhao were able to control the floods. Instead of thinking of building a dam across Minjiang (Min) River to control flooding, the duo was compelled by the prevailing circumstances of war to take what was otherwise a difficult decision but one which earned them many pages in the annals of Chinese history (Wintle, 2002).

More telling was the input of Governor Li Bing who conceived the idea to control flooding through the construction of levees as opposed to building dams. While the infrastructure of an original basket of stones and tripods has been replaced with concrete and steel reinforcement, the design of the waterway gives a glimpse of Chinese scientific prowess. The state of Shu especially on the Chengdu agricultural plains had suffered flooding from the Minjiang River every summer. Many attributed this flooding to the work of the evil dragons that came to receive human sacrifice every time there was flooding (Cheng, 1995). However, one man was thinking differently: Governor Li Bing. He discovered flooding was being caused by the thawing of the ice caps of the local mountain accompanied by seasonal rainfall. The only solution available was to seek ways of building a water control system.

The volume of water flowing into the rivers increased causing flooding downstream. There were two options available: building dams across the river or more difficult, building levees along the river banks. However, the easier option of building dams was unlikely as the Minjiang River was instrumental in transporting troops and armaments to the lower parts. Therefore being the leader, Li Bing concluded that building dams could have only transformed the problem of flooding into a military transport crisis. Indeed it required a mind of a genius to think about the alternative: to build levees along the river. It was a plan chattered to divert some of the water into another course to control the flooding of the remaining volumes of water. However, another challenge stood in the way to redirect the water. There was a mountain: Mount Yulei. Beyond there were the Chengdu plains that were arable land with high agricultural potential but which was bedeviled by flooding (Zang and Changshu, 2006). Farmers in the area lost all their crops to floods.

Along the banks of the river, Governor Li Bing decided to build levees to stop flooding. It was not an easy task but through the resilience of the people and the wisdom of the Governor the project was completed and the problem of flooding was permanently solved. Building these barriers controlled the flow of the water, even as it remained the mode of transport. The area that was prone to flooding was converted into an irrigation system that feeds millions of people to date. Built-in 256 BC Dujiangyan irrigation system is one of the oldest Chinese wonders of technology developed by Governor Li Bing. Alongside the Zhengguo Canal in Shaanxi Province and the Lingqu Canal in Guangxi Province, the Dujiangyan system irrigates more than 5,300 square kilometers of land and is called ‘ The three great hydraulic engineering projects of the Qin Dynasty’ and provides water to more than 50 cities in the province (Huang and McBeath, 2008). After completion of this project flooding has never occurred in the area. It was an example of human resolve against the forces of nature.

Statement of the Dujiangyan irrigation project

According to Travel China Tour, the Dujiangyan irrigation project consisted of three major constructions that work together to control flooding along the river. These are Fish Mouth Levee (Yuzui), Flying Sand Weir (Feishayan Fence), and the Bottleneck Channel (Baopingkou). Fish Mouth Levee was a barrier constructed shaped like a fish head, to split the water into two streams: inner and outer streams. The inner stream ran through the Chengdu plains and provided water for irrigation while the outer stream controlled silting and sediments deposits in the river in the original course. During flooding seasons the inner canal carries 60 percent of the water while the outer stream carried 40 percent of the water.

The silt and sediments are carried in the outer stream. During the dry season, the outer stream carried 60 percent while the inner stream carried the remainder. The Bottle Neck Channel was dug out of the mountain and was used as the gate to control the water along the channel before the excess was released to the Flying Sand Fence (Wintle, 2002). The inner stream leads to the Bottle Neck Channel which leads to Chengdu plains. The channel is the entrance to the extensive irrigation system in Sichuan Province. The canal was dug out of Mount Yulei assumed a shape of a bottle and hence the name. It controlled the amount of water that flowed into the Sichuan irrigation plains. Flying Sand Fence connects the controls water from the inner canal joining the outer canal. The fence is beneficial during the flooding seasons where it helps to stem flooding controlling the water entering the outer canal. It provides natural swirling of the water forming whirlpools sweeping the sand and pebbles into the outer stream over the Flying Sand Fence. During the dry seasons as there are lower levels of water, the fence is of little purpose. The system forms a complex engineering and drainage network that works together to control flooding along the Minjiang River.

Li Bing designed this water control project and was implemented by the Chinese people who were yearning for a solution to the problem of flooding. It took the people of Sichuan Province twelve years to complete the entire project. Indeed digging a channel through a mountain was an ambitious plan but one that not only alleviated the problem of flooding but also provided a source of livelihood for the local people. Today the Dujiangyan irrigation system benefits across 33 counties to the West of Sichuan.

List of options for the Dujiangyan irrigation system

Li Bing had to deal with two major problems while maintaining the water flowing without obstructing it: flooding and silting. Li Bing investigated the problem and established that melted water from the mountains and sitting on the lower parts of the Minjiang River caused flooding and untold suffering for the people of the area. One of the possible solutions was to build dams along the Minjiang River to control flooding. However, the Minjiang River was important in transporting military personnel to the frontiers. Due to its importance as a mode of transport, the challenge was how to solve the problem without hindering the transport of soldiers down the river.

The alternative was a massive project of building levees and digging canals that took more than twelve years and tens of thousands of people using rudimentary tools and obsolete technology (Zang and Changshu, 2006). It took four years using ‘sausage like’ bamboo basket containing stones reinforced with wooden tripods to build the levees along the river and another eight years to dig 20 meter-wide canal through Mount Yulei. This system availed the water for irrigation in Chengdu plains and controlled flooding on the other tributary.

Digging the canals was difficult. At the time, there was no gunpowder or dynamite to explode the rocks and the king and his people used fire to heat the stones and water for sudden cooling to effectively crack the stones. The result was a canal that changed the course of part of the Minjiang River (Huang and McBeath, 2008). This infrastructure turned water that had naturally been a flooding disaster to a farming resource. The digging of canals through Mount Yulei and de-silting of the river meant that people of Qin Dynasty had not only solved a old age problem of flooding but had also provided a source of income through farming in Chengdu Plains.

With the level of technology of the time the project was created still fascinate many scientists to date. Today the project that took many years to complete is not only a farming resource but also an attraction to tourists into the area. It is a project that man used calamities for his own benefit. It is the ingenuity of Governor Li Bing and the resolve of the Chinese people to solve a problem that nearly converted the King into an idol of worship in the area. The benefit of this hard work was extensive development projects that feed millions of people to date.

After this development Sichuan Province become one of the most agriculturally productive areas in China. Today Dujiangyan irrigation system is a major scientific attraction in China. The site has drawn a lot interests from among other people archaeologists to geologists and farming experts studying the origin of and use of levees to control flooding unlike the use of dams to block the water. Li Bing used levees to direct the course of the river and completely solve the problem of flooding in the area. Indeed Dujiangyan was been named in 2000 by the United Nations Educational, Scientific and Cultural Organization (UNESCO) as a World Heritage Site. It is achievement that has converted Li Bing into being more than just mortal. Most of the temples in the province have his statues depicting the cardinal role that he played in developing the area.

Statement of other relevant facts and consequences of each option

People of Sichuan Province suffered the problem of flooding for many years. However, no one ever bothered to seek a lasting solution until the time of Governor Li Bing in 256 BC. Every time during summer, the ice caps from where the rivers originated, would thaw causing increased volumes of water in the river. This caused flooding in the lower plains of the Chengdu. Farmers in the area suffered losses every time when the rains fell or during summer (Toriyama, Heong and Hardy, 2005). Due to significance in water transport dams, could not be constructed across Minjiang River. And the problem persisted as people suffered more losses to floods. There were two alternatives but each had its consequences and shortcomings. One was to build a dam across the river while the other which was more difficult to design and implement was building levees along the river (Wintle, 2002). Building dams could have been easier to control flooding but the river was used as a mode of transport for the soldiers. This therefore prevented the leaders from opting to build dams and therefore choose the more difficult alternative to build levees and dig canals to control flooding.

According to Travel China Tour building levees did not only control the floods but also provided water for irrigation for the people of Sichuan province. Cement had not been discovered and Governor Li Bing decided to use bamboo baskets filled with stones to build levees to control the levels and speeds of water. The baskets were reinforced with large tripod sticks fastened with ropes. This was the system to control the flooding.

However the challenge was digging of the canal through a mountain at a time when there were no explosives. However hard work and resolve of the people paid up later after the completion of the oldest non-dam irrigation project. The project did not only control the flood waters but also provided the same for Dujiangyan irrigation system. The irrigation system today provides food and water for millions of people. The man behind this construction Li Bing has become an idol of worship with many temples in the area having his statue for worship. The awe with which the Sichuan people viewed Li Bing shows the kind of belief that probably they held about flooding. They believed it was work of gods to punish them and therefore never bothered to find a solution of the problem (Cheng, 1995).

Statement of relevant moral principles

As is with all ambitious and revolutionary projects, people sometimes become apprehensive. This was fate that awaited Li Bing ambitious plan to build the levees to control the flow of flood waters on Minjiang River (Huang and McBeath, 2008). While no resistance has been documented, the people believed the flooding was the work of evil dragons and may have been worried that controlling the floods could have backfired on them causing bad luck (Cheng, 1995). However the Governor Li Bing was thinking otherwise. He knew that by encouraging the people to build the levees he would have solved the problems once and for all. Military troops could use the water for transport and the excess water could be used for irrigation of the potential farmlands in Sichuan province. After the project was completed, Li Bing almost immediately became a hero who had overcome the adversities of nature and triumphed over the raging floods that caused the problem to the local people.

The story gives an insight of the benefits of resolve and focus based on knowledge. Most of the natural disasters that bedevil people can be turned into resources if the people are equipped with the right attitude and technology. Initially it was not easy to conceptualize the outcome of the project. It is only after it was completed that the locals were able to fathom the intelligence of their leader. They could now enjoy the benefits of the project in transport and irrigating their land. Gouging a canal through a mountain with bare hands was indeed a difficult task. But it was a task that Li Bing found though difficult was possible. He was able to actualize the results of the project before its inception. Needless to say that many people may have died before the project was completed but the leadership remained focused on the ultimate goal of solving the problem of flooding.

Statement of taking Dujiangyan irrigation for study case

Many places around the world suffer the problem of flooding. Flooding that causes suffering, death of people and destruction of property. Many people who have chosen to ignore the problem and opted to learn to live with it. Few who have thought about the solution have relied on building dams to control the flow of water (Toriyama, Heong and Hardy, 2005). But Li Bing was thinking differently probably not out of choice but lack of it. Yangtze River with its tributary Minjiang was an important mode of transport. The troops needed to use the rivers but at the same time there was need to control the flooding. According to Travel China Tour website these two problems could not be solved simultaneously through building of dams across the rivers. This led to many years of research and study and later the design of an alternative method of building levees and canals. The benefits of the projects became clear after the completion of the project after large tracts of land were availed for irrigation from the water harnessed from the river Minjiang. Water in the river was conveniently balanced so that the outer and inner streams could share the water and control flooding. This led to the Dujiangyan irrigation project.

Justification of choosing Dujiangyan irrigation system

In no uncertain terms the project was complex, at least with the then available resources and technology. While many people had resigned to work of the gods and forces of nature, only a few like Li Bing could think of solving the problem. The problem of flooding in the Sichuan Province had not developed overnight but has stayed with people and they had gotten used to it. The problem persisted and the result was designing a hydraulic drainage system that even today is a wonder. How this achievement was arrived at without the use mathematical theories and extensive research is mind boggling. But Li Bing achieved this feat with tenuous people of China. Dujiangyan irrigation system has been one of ancient examples of early civilization which has stood the test of time (Zang and Changshu, 2006).

Dujiangyan hydraulic system remains one of ancient wonders of technology. Using sticks and stones to build levees as well as using bare hands to dig large canals through a mountain is an effort that cost people their energy and time but it was the only way to solve a problem that had dogged the community of Sichuan province for a long time. Today concrete and steel reinforcement has replaced the old bamboo and stones architecture. But the design of the entire project still remains the same and continues to benefit the people.

References

Cheng M. (1995). The Origin of Chinese Deities. Beijing: Foreign Languages Press. pp. 170–180.

Dujiangyan Irrigation System.

Huang, J. and McBeath. (2008). Environmental Change and Food Security in China. Berlin springer.

Toriyama, K, Heong, L. and Hardy, B. (2005). Rice is Life: Scientific Perspectives for the 21str Century : proceedings of the World Rice Research Conference, Tsukuba. Manila: International rice research institute.

Wintle, J. (2002). The Rough Guide History of China. London: Rough Guides Ltd.. p. 78.

Zhang, K and Changshu, H. (2006). World Heritage in China. Guangzhou: The Press of South China University of Technology. pp. 95–103.