China’s humongous Three Gorges Dam is making days longer
The reservoir can hold 42 billion tons of water when the dam is fully operational
The Three Gorges Dam in China, called for the three gorges it spans, is the world’s largest hydroelectric dam and the reservoir of the dam is capable of holding so much water that it is said to change the Earth’s rotation, making days marginally longer
This huge dam is located among three adjacent gorges — Outang, Wu and Xiling.
The steel and concrete dam is 7,661 feet long and about 600 feet high. The huge dam required 510,000 tons of steel for construction. In comparison, the same resources might be used to construct 60 distinct Eiffel Towers.
There have been even claims that the dam is viewable from the space, but this is not true as it has not been proven so far.
Sun Yat-Sen proposed the idea of Three Gorges Dam
Sun Yat-Sen, also called the father of modern China, originally proposed the idea of Three Gorges Dam way back in early 1919. He advocated the dam in an article as a way to develop China’s manufacturing industries.
Sun Yat-Sen suggested the idea of building a dam to assist control flooding on the Yangtze River while also symbolizing China’s “new might” in an article titled “A Plan to Development Industry.”
Pertinently, the Yangtze River is the longest river in Asia and the longest river in a country in the whole world, which, as per some estimates, contributes over 20% of China’s Gross Domestic Product (GDP).
Dam became a reality after decades of delays
Since its announcement in 1944, the Three Gorges Dam has been mired in controversy and delays. The Three Gorges Dam was not considered until 1944 after Sun Yat-sen proposed it in 1919. The Republic of China secured a contract with the United States Bureau of Reclamation to design the project in 1946. However, due to the Chinese civil conflict that followed World War II, this initiative was quickly abandoned.
Also, the project was originally slated to complete in 2008 but spiralling costs (total cost of the dam have ranged from $25 billion and soared as high as $37 billion by some counts), environmental concern, Chinese political corruption, and resettlement issues caused the project’s progress to slow and at times, came to a complete halt.
Serves three major purposes in China
The dam is hugely beneficial for China as it has contributed in multiple ways — be it avoiding floods, generating power or improving navigation.
Floods, which were a huge problem for the country and claimed the lives of 4 million people in 1931, have been mitigated to a large extent since the reservoir started to become operational.
It kept the river at bay during the flooding season, helping protect millions of homes and lives downstream as well as important Chinese cities that sit adjacent to the Yangtze river like Wuhan, Nanjing, and Shanghai.
Manufacturing and industry in the country also required a huge supply of electricity and the dam became one of China’s key hydroelectric power production assets.
Three Gorges Dam even defeats the gigantic Hoover Dam, which generates around 4 billion kilowatt-hours of hydroelectric electricity per year and enough to supply 1.3 million people. The Chinese dam generates 11 times more power, comparatively. The amount of electricity generated is so huge that the Three Gorges Dam is thought to be able to power the entire nation of China.
Besides, the improvement in navigation is a significant bonus for the East Asian country.
Negative impact on environment
Given the benefits of the dam, there are some bitter facts about it that have become a cause of worry for the people in China. Certain estimates state that 70% of China’s fresh water is polluted and the dam could be making it a lot worse.
In the region surrounding the Three Gorges Dam, it is home to 6400 plant species, 3400 insect species, 300 fish species and more than 500 terrestrial vertebrate species. These species are also said to have been affected to some extent.
In fact, the erosion of the reservoir has triggered landslides and has even threatened the world’s biggest fisheries in the East China Sea.
Three Gorges Dam slowed Earth’s rotation
The National Aeronautics and Space Administration (NASA) has confirmed that the dam has been responsible for slowing the rotation of the planet Earth and the secret behind this phenomenon is inertia.
When the dam is at its maximum, the reservoir holds about 42 billion tons of water which makes the Earth lose a bit of momentum when rotating. A shift in mass of that size does affect Earth, increasing the length of a day by 0.06 microseconds.
Even though this rotation of Earth is actually slowed down quite often due to other factors also such as the moon’s position, earthquakes and climate change-induced movement of the North Pole.
What is even more interesting is that the rotation of the Earth also affects time. Every five years or so, the day is made longer by one millisecond. NASA has calculated that the dam only slows the rotation by 0.06 microseconds, which is six-hundredths of a millionth of a second.