The Three Gorges Dam is located on the Yangtze River in the Hubei province of China. It is the largest power station in the world when looking at its installed capacity of 22,500 megawatts. It set a world record for generated terawatt-hours in 2014, just two years after becoming fully functional. The final phase of the project, the bypass locks for shipping, was completed in 2015.
The primary advantage of the Three Gorges Dam is that its design is intended to stabilize the river patterns in the region. Not only will it still support shipping along the Yangtze river, but flood storage space has also been provided so that downstream agricultural activities and riverside communities face lower annual risks of flooding during the rainy season.
The disadvantage of the Three Gorges Dam is that there are sedimentation and erosion hazards that are associated with the project. About 80% of the land area around the dam is experiencing problems with erosion, which produces over 40 million tons of sediment that is deposited into the river each year. Much of that sediment settles around the dam, placing more weight on the seismic fault the dam happens to sit on.
Here are more Three Gorges Dam pros and cons to take a closer look at as well.
List of Pros for the Three Gorges Dam
1. It has a positive environmental impact on emissions.
The National Development and Reform Commission of China reports that the Three Gorges Dam reduces coal consumption by up to 31 million tons annually. Assuming that it takes 366 grams of coal to produce 1 kilowatt-hour of electricity, the dam can avoid more than 100 million tons of emissions each year while maintaining current electricity levels. That includes 10,000 tons of carbon monoxide.
2. The Three Gorges Dam offers various ways to save energy.
Because the Three Gorges Dam creates high levels of hydropower, it reduces the need to transport and clean coal for energy production. By increasing barge capacities while reducing train and overland vehicle transportation, the energy savings reduced carbon dioxide emissions by up to 10 million tons and reduced utility operational costs within the region by up to 25%.
3. The dam has improved recreational access along the river.
The developing river cruise industry along the Yangtze has dramatically improved as the dam project has moved along. Since the installment of the ship locks and the ship lift with the dam, cruise ships have a natural tourism point that supports the stunning views that can be seen along the river corridor.
4. It has improved hundreds of kilometers of waterways.
The reservoir for the Three Gorges Dam reaches the metropolis of Chongqing in the southwest. It supports shipping fleets that originate in Shanghai and can reach Chongqing with much greater ease than before the placement of the dam. That means, in total, over 660 kilometers of river have been improved with the project, creating an increase in annual one-way navigation capacity of more than 40 million tons.
5. It offers a renewable power resource.
Hydropower is considered a renewable resource, though some may not classify it as such because of its impact on water flow and fisheries. Fueled by water, it is a clean fuel source. It is a sustainable form of power that supports localized irrigation where it may be needed along the Yangtze as well. That makes it a reliable future power resource for the region while offering new economic opportunities, such as swimming, boating, and fishing.
6. The Three Gorges Dam was an affordable project.
Even though it is 600 feet in height and over 7,600 feet long, the total cost of the Three Gorges Dam project was an estimated $26 billion. In return, China is able to have a power resource that could provide enough energy to power the cities of Washington, D.C., Boston, and New York City. It is so large, in fact, that research suggests it has slowed the Earth’s rotation by .06 milliseconds upon its completion.
List of Cons for the Three Gorges Dam
1. It has increased water pollution levels.
The erosion being experienced around the Three Gorges Dam has dramatically increased sediment. Though it is concentrated around the dam, there are downstream influences that can be seen with the higher sediment levels. The increased shipping levels experienced on the river have increased water pollution levels as well.
2. It has created a human migration problem.
Officials in China expect that the flood reservoir from the Three Gorges Dam will eventually inundate 2 cities, 140 towns, and over 1,300 villages. To fully accommodate the potential of the reservoir, the government will be forced to resettle over 1.1 million people. In total, nearly 24,000 hectares are expected to be inundated when the dam creates a reservoir which reaches its full capacity.
3. The Three Gorges Dam has changed the landscape.
Although the reservoir created by the dam project has improved shipping and offered new habitat options for local wildlife, it has taken away options as well. Plants and animals that called the river home have been devastated by the effects of the project. The surrounding landscape has shifted dramatically to the point where even the localized climate has been altered. Some wildlife and disappeared outright. Historic relics have been covered by the reservoir.
4. Local infrastructure struggles with the dam’s total capacity.
Even though it achieved a world record for output, the Three Gorges Dam is still an inefficient power facility. Local power distribution infrastructure is still catching up to the total production capacity. Much of the distribution is focused on urban centers as well, which means those in rural areas, which have borne most of the brunt of this project, see little of the rewards that are offered.
5. It has been known to trigger earthquakes.
The erosion that occurs within the reservoir of the Three Gorges Dam, along with the weight of rising water levels and the dam itself, has been known to trigger earthquakes. Major landslides have led to noticeable disturbances within the reservoir and have possibly contributed to the earthquakes being experienced as well. In just 4 months, there were nearly 100 significant landslides in the region. A 2011 study from the China Earthquake Administration noted more than 3,000 earthquakes in the region, directly attributed to the project.
These Three Gorges Dam pros and cons suggest that this hydropower project has a lot of potential to do good for China and the Yangtze. If the issues with erosion can be controlled to prevent future landslides, perhaps fewer earthquakes could be triggered. In return, more world records for power generation may be able to be achieved as the dam is able to reach its fully capacity.