The Dujiangyan irrigation system, located in the western part of the Chengdu Plain in southwest China, is an ecological engineering feat originally constructed around 256 BC.

As the only remaining grand water conservancy project in the world, it has withstood natural disasters such as floods and earthquakes, and is still in use today.

Characterized by dam-free water diversion, it has tamed floods, nourished farmlands, and sustained the prosperity of Sichuan province for over 2,000 years.

The system comprises two parts: the Weir Works, located at an altitude of 726 meters, the highest point of the Chengdu Plain, and the irrigated area.

Thanks to digital and intelligent transformation of the Dujiangyan irrigation system, such as digital twin reality modeling and automated water metering facilities, the management of the irrigated area has entered a new phase of "intelligent-driven and precise decision-making."

"The irrigated area of the Dujiangyan irrigation system is continuously expanding," Li Yanfu, deputy secretary of the Party committee of the Sichuan Dujiangyan Water Conservancy Development Center, said.

Its effective irrigated area has increased from 2.86 million mu (1 mu equals 666.7 m²) in the early years of the People's Republic of China to 11.65 million mu in 2025, serving a population of more than 30 million across eight cities and 41 counties (county-level cities, districts) in Sichuan, according to Li.

Zizhong, a county in the central Sichuan Basin, is one of the beneficiaries of such an increase. Agriculture in the county's towns such as Falun and Qiuxi was long dependent on rainfall. But the arrival of water from the Minjiang River changed the situation.

In October 2025, the nearly 30-kilometer-long Sanhuang branch canal officially started operation, delivering water from the Minjiang River via the Dujiangyan irrigation system to the Dongfeng reservoir in Zizhong. This injects vital hydraulic power for developing high-quality grain, oil, fruit and vegetable industries in the area.

"Now that water is easily accessible, I feel much more confident about a bumper harvest!" Lv Desheng, a farmer from Qiuxi town, said.

At present, the annual water supply of the irrigated area is stabilized at over seven billion cubic meters.

"The irrigated area is a veritable grain barn and wealth reservoir," Li said. "With less than one-twentieth of Sichuan province's land area, it now produces nearly one-quarter of the province's grain output and contributes almost half of its regional GDP."