Dujiangyan Irrigation Project of China

The astounding longevity of Chinese civilization has been strengthened by numerous scientific, engineering, and infrastructural masterpieces that have been created throughout the course of history.  Completed in the year 256 BC, the Dujiangyan Irrigation Project has endured as the world’s oldest and only remaining water conversancy system that functions without a dam.  The project occupies the western portion of Dujiangyan City, just outside of Chengdu.
The project was proposed as a solution to frequent flooding due to the Minjiang River, a tributary of the Yangtze that threatened the city.  Signifying a critical development in Chinese science, the project was the result of lengthly research and ingenuity on behalf of Li Bing, a local Sichuan Official, and the local people involved in the construction process.  The project is composed of three main elements; the Yuzi Watershed that creates a division in the Dujiang River resulting in an Inner and Outer River, the Feisha Spillway that functions to shift sand and stones from the Inner to Outer River, and the Baopingkou that regulates water flow because of its bottle neck design.  The three components work together to form a highly effective system of water conservancy.  The project has directly aided in the transformation of dry land into fertile fields by capitalizing on the region’s geological conditions, designing irrigation paths that use altitude and water flow to reach farmlands without the implementation of a dam.  The Dujiangyan Irrigation Project continues to be renovated, repaired, and expanded so that it can continue to benefit the region for generations to come.  It was enlisted in 2000 as a UNESCO World Heritage Site, and remains to this day one of China’s greatest engineering marvels.