It is the rainy season. The water level in the rivers is rising. In such a situation, the importance of dams increases. If there are no dams, water enters residential areas. Dams are beneficial in preventing floods. In generating electricity. But there is one dam which is controversial. This is the world’s largest dam.
You will be surprised to know about the damage caused by China’s Three Gorges Dam. This dam has slowed down the speed of the Earth’s rotation. The world’s largest dam is in China, named ‘Three Gorges Dam’. This is a hydroelectric gravity dam.
It is built on the Yangtze River in Hubei province of China. Yangtze is the third longest river in the world. The length of this river is more than six thousand kilometers. History is witness to the heavy floods in the Yangtze River. Its banks used to overflow once every ten years. During the 20th century alone, about 3 lakh people were killed due to floods in it.
Size, height, cost… everything is insane
This dam was built to control floods and save 1.5 crore people and lakhs of acres of agricultural land. Made of steel and concrete, this dam is 2.3 km long, 115 meters wide and 185 meters high. It is the world’s largest dam, so obviously it will be the most expensive too. The cost of construction of this dam has been estimated to be more than Rs 2.5 lakh crore. It took almost two decades to complete. Its construction started in the year 1994. It was completed in 2012.
Thousands of tons of steel were used
Four lakh sixty three thousand tons of steel has been used to build the Three Gorges Dam. 60 Eiffel Towers can be built with this much steel. This dam is producing so much electricity that many small countries can be illuminated with it. It has the capacity to generate 22,400 megawatts of energy.
Why is this dam controversial?
Although China claims to have been successful in preventing flood waters, the Three Gorges Dam is surrounded by controversies regarding water pollution and environmental hazards. Even today, China is facing heavy rains and severe floods. This raises questions about the efficiency of the dam.
Impact of landslides and floods
When the plan to build the dam began in 1992, many scientists had warned that the dam would increase pressure on the surrounding islands. This could lead to landslides. Biodiversity would be at risk. In 2003, 700 million cubic feet of rock fell into the Qinggan River, 2 km from the Yangtze. 14 people lost their lives in this.
Despite this, the China Yangtze Three Gorges Development Corporation raised the water level in its reservoir from 445 feet to 512 feet. This caused dozens of landslides. In 2020 too, the dam gates were opened due to flood waves. It was a flash flood. Since then, the Yangtze River has been battling floods.
Hundreds of people have lost their lives in many parts of China due to floods. More than 14 lakh people have been displaced. Their houses have been destroyed. Hundreds of acres of agricultural land have been submerged in the floods. Two cities and more than 100 towns and 1600 villages situated on the banks of the Yangtze River have been submerged.
The weight of the water destroyed important parts of the Yangtze River’s banks. This has raised questions about the dam’s efficiency. Experts say it can withstand small floods, but not large ones.
Dam has caused many losses
This dam is built on two major fault lines. That is why earthquakes occur here. In 2003, a large part of a mountain broke and fell into the river, killing 24 people. Once, cracks also appeared on the dam wall, which increased the risk of leakage.
There are 6400 plant species, 3400 insect species, 300 species of fish and more than 500 terrestrial vertebrate species found in the area around the Three Gorges Dam in China. These species have come under threat because of this dam. Drought and diseases have also increased due to the Three Gorges dam.
Particularly in 2008, the Yangtze River’s water level was the lowest in 142 years. Many homes have
been affected due to the reduction in water flow. Fresh water has become contaminated. It is
estimated that 70% of China’s fresh water is polluted. The dam is making it even worse. This dam is
built on top of old waste facilities and mining operations. 265 million gallons of sewage accumulates
in the Yangtze River every year.
the speed of rotation of the earth has decreased
The biggest impact of this dam is on the earth. NASA scientists calculated in 2005 that the speed of the earth’s rotation has slowed down due to the Three Gorges Dam. There are many things that affect the earth’s rotation. Such as winds, earthquakes, climate change and even the position of the moon. The dam’s reservoir has 42 billion tons of water, due to which the earth loses its momentum while rotating.
Due to the change in mass, the time of one day has increased by 0.06 microseconds. That is, because of this dam, the day has become a little longer. According to NASA, because of the construction of this dam, the North and South Poles have also shifted 2-2 centimeters from their respective places, while the Earth has become a little flat on the other poles..
Discussion about this post