About 2300 years ago, the area around Chengdu had bad floods (洪水) in spring every year. Flood water from the mountains flowed (流动) down the Minjiang River and covered the land. Luckily, the Qin governor (太守), Li Bing, was a water engineer. The king of Qin provided the money and asked the governor to solve the problem.
The usual method to avoid flooding is to build a wall across the river, called a dam. Special openings in the dam allow the flow of water to be controlled. However, the king had also asked Li Bing to make sure that ships could still use the river. This was necessary because the king needed to send food to his army. So Li Bing studied the situation and came up with a plan—a plan that still works today!
Helped by his son, and tens of thousands of workers from the area, Li Bing built a man-made island in the middle of the river. This island was shaped like a fish and it divided the water into an inner and an outer river. The inner river was deeper than but not as wide as the outer river. It took four years to build the island.
Li Bing also cut a new channel (运河) through Mount Yulei. This channel would take water away to irrigate (灌溉) the land in the flat farmland below. The rock of the mountain was very hard and difficult to cut. Li Bing used fire to heat the rock and then water to cool it quickly. This made the rock break into smaller pieces which could be carried away more easily. Cutting the channel took eight years!
After Li Bing's work was finished, there were no more floods, and the Dujiangyan irrigation system (灌溉系统) allowed the farmers to grow more and more food. The river flowed naturally, and because there was no dam, ships and fish could pass freely. Sichuan became the most productive area in China, as it still is today. Today, scientists and visitors from all over the world come to look at this wonderful example of engineering. This work and the name of Li Bing live on.
