Record-breaking project still bringing manifold benefits

The Three Gorges Project, as the world's largest water control and hydroelectric project, has delivered immense benefits in mitigating flooding, power generation, navigation and water regulation.

"Since its construction, the Three Gorges Reservoir has successfully controlled flooding on almost 70 occasions, with a total volume of intercepted floodwater exceeding 220 billion cubic meters," said Xu Changyi, Three Gorges Group's Party chief for the hub operation and management of the Yangtze River Basin.

At the junction of the upper and middle reaches of the Yangtze River, the Three Gorges project is located adjacent to the most severe flood-prone section of the Jingjiang River — an alternate name for a section of the Yangtze's middle reach that winds and twists. These characteristics make it challenging for efficient flood passage — and thus enable it to control over 95 percent of the floodwater in the Jingjiang River and about two-thirds of the floodwater above Wuhan, Hubei province, a populous city and an important industrial hub, according to Xu.

"The primary function of the Three Gorges Project is flood control, and the greatest benefit is also derived from flood control," Xu added.

During the flood season in 2020, the Three Gorges Dam successfully controlled five major flood events, with a peak storage capacity in the reservoir of 29.5 billion cubic meters.

The Three Gorges Dam demonstrated its remarkable flood control capability in the fifth major flood, the largest flood since its inception. It cut the maximum flood peak flow from 78,000 cubic meters per second to 49,400 cubic meters per second, reducing these flows by more than a third, effectively avoiding the evacuation of 600,000 people and the flooding over 32,670 hectares of farmland, according to Xu.

The floodwaters of the Yangtze River have not only been controlled but also converted into a massive amount of electric power.

In 2020, the Three Gorges Power Plant generated 111.8 billion kilowatt-hours of electricity, setting a world record for annual power generation volume, according to Cai Wei, deputy head of the Three Gorges Power Plant.

As of early October this year, the cumulative power generation of the Three Gorges Power Plant had reached 1.66 trillion kWh, equivalent to saving 528 million metric tons of standard coal and reducing carbon dioxide emissions by 1.43 billion tons, Cai added.

The Three Gorges Reservoir, with its large volume of water and excellent water distribution capability, has evolved into a critical strategic water regulator, said Xu.

The reservoir has replenished more than 360 billion cubic meters of water to meet the demand for water use in the middle and lower reaches of the Yangtze River for a cumulative 2,686 dry season days.

The shipping capacity of the Yangtze River has also been significantly enhanced, with the joint operation of the ship lock and the ship lift of the Three Gorges, enabling water traffic to pass smoothly.

The five-tier ship lock allows vessels of up to 15,264 metric tons to navigate past the dam, and the ship lift enables vessels of up to 3,000 tons to pass in about 40 minutes, according to its operator.

As of early October, the ship lock has opened its gates 207,000 times since its inauguration in 2003, facilitating the passage of 1.05 million vessels and a cargo volume exceeding 2.12 billion tons, according to Cheng Hang, deputy director of the Three Gorges Group's hub operation and management center for the Yangtze River Basin.

As of early October, the ship lift has transported 29,000 vessels, and carried 1.39 million passengers and 18.11 million tons of goods since its inauguration in September 2016, according to Cheng.