Answer: The Dujiangyan system consists of the headworks (the Fish Mouth Levee, Flying Sand Weir, and Bottle-Neck Channel) and an extensive irrigation network. The Fish Mouth Levee divides the Min River into an outer and an inner channel, achieving the principle of "diverting 60% of the flow for irrigation and 40% for flood discharge to balance water in both floods and droughts". In dry seasons, 60% of the river’s flow is directed into the inner channel for irrigation, while during floods, 60% is diverted to the outer channel to prevent flooding. This remarkable design showcases the ancient Chinese wisdom of dam-free, eco-friendly water management.

Image: Tuchong