Overview of the Three Gorges Dam
The Three Gorges Dam, located in the Yangtze River valley in central China, is the world’s largest hydroelectric dam. It is a colossal project that has changed the river’s ecology and demographics, created a reservoir of epic scale, and generated vast amounts of electricity. The dam stands 202 meters high and is 2,335 meters long. It impounds a reservoir that runs for 660 kilometres and has displaced over one million people, making it the largest displacement of humans ever recorded.
Construction and Operation of Three Gorges Dam
Construction of the Three Gorges Dam began in 1993 and it officially began to generate electricity and power nearby cities in July 2003. In 2012, the dam’s generating capacity was 26.5 gigawatts — enough to power 80 million people. The operation of the dam is part of a two-tier system in which a narrow, limited-flow impoundment sits above a maximum-flow impoundment. This two-tier system allows for improved water supply and weather protection for flooding. The dam contains a series of ship locks, allowing ships to move up and down the river — and the locks accommodate some of the largest vessels on the Yangtze River.
Environmental and Social Changes of Three Gorges Dam
The effects of construction and operation of the Three Gorges Dam have been both positive and negative. The dam has created vast amounts of clean energy, protected nearby cities from floods, and allowed navigation and commerce up and down the Yangtze River. On the other hand, it has caused drastic changes in the Yangtze’s environment, with devastating effects on biodiversity, including the destruction of entire fish species, the destruction of ecosystems, and the destruction of cultural sites. Additionally, the displacement of over one million people due to the creation of the reservoir has been a cause for concern among human rights advocates, who worry about potential health effects on those forced to leave their homes.
Costs of Three Gorges Dam
The cost of building the Three Gorges Dam was estimated to be $30 to $45 billion US dollars. The majority of this cost was paid by the Chinese government, and the remainder was funded by public subscription. In addition to the upfront cost of construction, the operating costs of the dam are estimated to be several hundred million dollars per year, mostly due to evaporation from the reservoir.
Geological Changes Due to Three Gorges Dam
The construction and operation of the Three Gorges Dam has also caused measurable geological changes. The impoundment of the reservoir has caused seepage of the water into the ground and contributed to the loss of 40-70% of the sediment entering the reservoir, causing the bed of the Yangtze River to become steeper and leading to more rapid erosion. Additionally, the reservoir has caused seismic activity in the region due to the increase in weight of the rock and soil below the reservoir.
Potential Economic Benefits of the Three Gorges Dam
The potential economic benefits of the Three Gorges Dam are difficult to estimate due to the long-term nature of the project and its effects on the environment and economy of the region. Proponents of the dam argue that the project will bring economic opportunities in the form of increased trade and tourism. In addition, the dam is expected to generate roughly $400 million per year in energy profits and create job opportunities in the region. However, opponents of the dam point out that the long-term effects of the project, particularly on the environment, could outweigh any potential economic benefits.
The Three Gorges Dam has improved navigation along the Yangtze River by providing a series of 5-tier locks that allow large ships to travel further upriver. This has made the river much more accessible and has opened it up to commercial shipping, reducing the price of goods in the region. In addition, the dam’s hydropower has been used to increase the depth of some of the main ports in the region, including the port of Shanghai, allowing bigger ships to access the port and increasing the number of goods that can be transported.
Conclusion of Three Gorges Dam’s Impact
The Three Gorges Dam is one of the greatest engineering marvels of the 21st century and has fundamentally changed the landscape of the Yangtze River valley. While it has undoubtedly provided economic and energy benefits, it has also caused irreparable damage to the environment and has displaced over one million people. Despite its immense size and power, the Three Gorges Dam is still perceived to be a controversial project — as its long-term impacts remain uncertain.
