1. Overview
The Dujiangyan Irrigation System (都江堰), constructed in 256 BC during China’s Warring States Period, is a 2,200-year-old hydraulic marvel designed by Li Bing, governor of Shu. Unlike traditional dams, it uses natural topography to divert the Minjiang River, combining flood control, irrigation, and sediment management. Recognized by UNESCO (2000), ICID (2018), and as a 5A-rated scenic area, it remains fully operational today.
2. Engineering Genius
The system comprises three core structures:
- Yuzui (Fish Mouth): A dividing dyke that splits the river into inner (60% water for irrigation) and outer (40% for flood discharge) channels.
- Feishayan (Flying Sand Weir): A spillway that removes 75% of sediment using centrifugal force.
- Baopingkou (Bottle-Neck Channel): A 20m-wide inlet carved through Yulei Mountain, regulating water flow to Chengdu Plain.
Key Innovations:
- "Low Weir, Deep Dredging": Maintains optimal water levels without dams.
- Seasonal Adaptation: Adjusts flow ratios automatically—60% to inner channel in dry seasons, reversing during floods.
3. Historical Impact
- Transformed Chengdu from a flood-prone basin to China’s most fertile region ("Tian Fu Zhi Guo").
- Enabled Shu Kingdom’s economic rise, aiding the Qin Dynasty’s unification of China.
- Inspired global irrigation systems, praised by German geologist Ferdinand von Richthofen as "unparalleled".
4. Modern Operations
- Irrigates 30+ counties (1.01 million hectares).
- Supplies 14.2 billion m³/year for industrial/domestic use in Chengdu.
- Integrated with Zipingpu Reservoir (2006) for enhanced flood control.
5. Visitor Experience
- Best Time to Visit: March–November (avoid summer floods).
- Must-See Spots:
- Erwang Temple: Honors Li Bing and his son.
- Anlan Suspension Bridge: Offers panoramic views.
- Tickets: ¥90 (free for seniors 60+).
Travel Tips:
- Combine with Mount Qingcheng (Taoist holy site).
- English audio guides available at the entrance.
Awards:
- UNESCO World Heritage (2000).
- ICID Heritage Irrigation Structure (2018).
For updates, visit Dujiangyan Official Site (Chinese) or Chengdu Tourism.
