The Three Gorges area, a place of mystical beauty and profound significance on China's Yangtze River, has long been the focus of a national dream. From initial conception to scientific validation, and from official commencement to full operation, the Three Gorges Project represents a century-long endeavor for the Chinese nation.
Officially launched on December 14, 1994, the project saw its main dam completed on May 20, 2006. By October 2008, construction was largely finished, and on November 1, 2020, the project passed its final overall acceptance, marking the successful realization of a dream pursued for a hundred years.
Over its 30-year construction and operational history, the Three Gorges Project has demonstrated its role as a "national landmark," delivering immense comprehensive benefits in flood control, power generation, navigation, water supply, and ecological protection. It stands as the most prominent new landmark on the Yangtze River.
President Xi Jinping, during an inspection on April 24, 2018, emphasized that the Three Gorges Project is a "critical national asset" and a testament to China's ability to undertake massive projects, the wisdom and creativity of its people, and the nation's growing prosperity.
Viewed from Tanziling Ridge on the left bank, the massive concrete and steel structure calmly restrains the mighty river, creating a serene "high gorges, flat lake" landscape. The vast reservoir stretches to the horizon, a haven for countless birds.
The journey began on April 3, 1992, when the Resolution to Build the Three Gorges Project was passed by the National People's Congress—the only construction project ever approved by a full NPC session.
After decades of dreaming, debate, and meticulous planning, the decision was made. It was a choice by the Chinese people, a pivotal moment heralding a new chapter in the nation's water management history.
Construction commenced on December 14, 1994, at the project site. Adopting a "single-stage development, one-time completion, phased impoundment, continuous resettlement" strategy, the project was divided into three phases over 17 years.
Phase I (1993-1997): Focused on preparatory works and the crucial river closure in 1997, diverting the river through a newly constructed channel.
Phase II (1998-2003): Aimed at building the left-bank dam sections, power plant, and the permanent shiplock, achieving initial power generation and navigation.
Phase III (2004-2009): Involved completing the right-bank structures and installing all generating units, leading to the project's full operational capacity.
The construction broke world records for concrete placement, with annual pours reaching 5.4 million cubic meters in 2000. A key achievement was solving the problem of thermal cracking in mass concrete, resulting in the right-bank dam being built without a single crack—a first in the history of large dam construction.
Technological Innovation: The Backbone of Success
In January 2020, the Three Gorges Project was awarded the National Special Prize for Scientific and Technological Progress, recognizing the immense intellectual contribution of thousands of engineers.
The project's design, led by the Changjiang Water Resources Commission, involved overcoming unprecedented technical challenges. Key innovations included:
- •River Closure: The 1997 main river closure and the 2002 diversion channel closure were feats of engineering, dealing with record water depths and flows. The "pre-placed cushion" technique was a groundbreaking solution.
- •Concrete Technology: The development of "secondary air-cooling of aggregates" and comprehensive temperature control methods enabled high-speed construction without cracks.
- •Turbine Generators: Through international cooperation and technology transfer, China mastered the manufacture of 700-megawatt turbine-generators, some of the largest and most complex in the world at the time, adapted to the Yangtze's unique conditions.
- •Shiplock and Ship Lift: The permanent five-stage shiplock, built into a deep rock cut, is the world's largest. Its innovative fully-lined design is a landmark in navigation structure engineering. The ship lift, commissioned in 2016, is the largest of its kind, allowing smaller vessels to "ride the elevator" over the dam.
Delivering Multifaceted BenefitsThe Three Gorges Project began demonstrating its value early. Initial impoundment to 135 meters in June 2003 marked the start of its core functions. By 2010, the reservoir reached its full capacity of 175 meters.
- •Flood Control: The project's primary function. Its reservoir has a flood control capacity of 22.15 billion cubic meters. It has successfully mitigated numerous major floods, including a record inflow of 75,000 cubic meters per second in 2020, significantly reducing downstream flood risk.
- •Power Generation: As the world's largest hydropower station, with a total capacity of 22,500 MW, it has generated over 1.7 trillion kWh of clean electricity since the first unit started in 2003. It plays a vital role in powering central, eastern, and southern China.
- •Navigation: The project has transformed the treacherous upper Yangtze into a golden waterway. It raised the water level, submerged dangerous shoals, and created a deep-water channel, allowing larger vessels and increasing cargo throughput dramatically. The annual lock transit volume exceeded 100 million tons in 2011, far ahead of projections.
- •Water Supply and Ecology: The massive reservoir acts as a strategic freshwater resource. It releases water during the dry season to supplement downstream flows, helping to combat saltwater intrusion in the Yangtze Estuary near Shanghai and meeting ecological and water supply needs.
The Three Gorges Dam stands not just as a concrete structure but as a symbol of human ingenuity and a testament to China's engineering prowess, delivering vast economic, social, and environmental benefits to the region and the nation.
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