Decision Context
| Scenario | Agricultural irrigation and flood control |
| Infrastructure | Gravity-fed irrigation network with natural water diversion |
| Hazard | Flooding, seismic activity |
| Monitoring | None (physical engineering principles only) |
| Regulation | UNESCO World Heritage protection |
| Decision Pattern | Flood barriers (natural levee), floodplain restoration |
| Use Case | Water supply security, flood risk management |
Knowledge Framework
Use Cases
- Operate flood defences during events — Decide when to close barriers, activate pumps, open sluices, or divert floodwater through emergen...
Decision Patterns
- Integrated flood systems — Combine infrastructure and monitoring
Overview
The 2,300-year-old Dujiangyan system is a brilliant application of fluid dynamics and environmental harmony. By dividing the river, utilizing spillways for overflow and de-silting, and controlling the final intake, it automatically manages water distribution and sediment control without any moving parts. It still irrigates vast tracts of farmland today.
Unlike modern dams that block a river, Dujiangyan’s genius lies in working with the natural forces of the Min River to control flooding and divert water for irrigation. Its enduring success is based on three construction principles: (1) Guiding, Not Confronting the River; (2) Three Core Components working in harmony; (3) Annual Maintenance with the “Deep Trenches, Low Weirs” principle.
Timeline & Location
256 BC: Construction under Li Bing and his son. 1933: Destroyed by Diexi earthquake, rebuilt same year. 2002: Renovation project costing 30 million yuan (USD 3.6 million). Located in Dujiangyan City, Chengdu, Sichuan, China.
Stakeholders
World Heritage Site status. Original builder: Li Bing (governor of Shu) and his son. Modern maintenance by Chinese government authorities.
The Three Core Components
The system operates through three ingeniously designed main structures that work in harmony:
Li Bing established the annual maintenance rule of “Deepen the channel, low the weir”. Each year during the dry season, sediment was dredged from the Inner River, while the Feishayan spillway was kept deliberately low for efficient overflow and sediment ejection.
Digitalisation & Data
None. The system operates entirely through physical engineering principles without any digital monitoring or data systems.
Hazards
Exogenous Hazards
Seismic activity, rainfall variations.
Endogenous Hazards
None identified — the simple architecture creates high resilience.
Cost & Benefit
Cost: 2002 renovation project costing 30 million yuan (USD 3.6 million) for maintaining and dredging, designed to allow the system to operate for another 2,000 years.
Benefit: Communities are not flooded. Farmers have fresh mountain water for irrigation. System operates without moving parts or energy input.
Resilience Principles Assessment
Assessment of meeting Principles of Resilient Infrastructure
Proactively Protected (P2)
Unlike dams which risk uncontrolled water release due to structural collapse, foundation instability, or overtopping, the design strategy of working with the natural environment strengthens its resilience.
Environmentally Integrated (P3)
In 2003, controversy surrounding threats to the Dujiangyan weirs from a proposed 1,200m Yangliuhu dam highlighted the linkage between natural and cultural heritage. In January 2004, China launched a movement to combat illegal destructive activities at national scenic and historic sites.
Socially Engaged (P4)
In 2003, Sichuan provincial authorities halted the Yangliuhu project, noting “this is the first time in China that the general public has had a say in a decision on an important project.”
More Information
Further reading on the Dujiangyan Irrigation System:
- UNESCO World Heritage — Mount Qingcheng and the Dujiangyan Irrigation System — official World Heritage listing and description.
- Dujiangyan Irrigation System — a world cultural heritage corresponding to concepts of modern hydraulic science — peer-reviewed paper in the Journal of Hydro-environment Research.
- Wikipedia — Dujiangyan — comprehensive overview of the system’s history, engineering, and preservation.
Futures
The original Dujiangyan irrigation system was destroyed in 1933 by the Diexi earthquake and was rebuilt in the same year. Although susceptible to seismic hazards, its simple architecture creates high resilience. The 2002 renovation was designed to allow the system to operate for another 2,000 years.