China’s gigantic Three Gorges Dam of the Yiling District is well on its way to spectacular disaster.
Officially known as the Yangtze River Three Gorges Water Conservancy Project, this hydroelectric gravity dam was finished in 2015 after 17 years of painstaking construction and stands as the world’s biggest power station, scaling 185 metres in height and 2,309 metres wide.
As well as simultaneously improving the Yangtze River’s shipping potential and the country’s economy, the Three Gorges Dam is there to protect millions of Chinese citizens from flooding on the Yangtze Plain.
Despite being considered a source of national pride by the government, this monstrous feat of engineering has attracted criticism on both home and foreign soil, with over one million individuals being displaced by its creation.
There’s also the natural implications of the thing, which we’ll dive into right now.
A black swan event
What with China’s new record rainfall, the dam’s adjoining river is now above flood level according to the Ministry of Water Resources.
Officials working at the Ministry even claimed that ‘peripheral’ structures are deformed due to the crazy water pressure constantly lying on it, but what would happen if the Three Gorges was somehow overpowered and breached?
That is what you might call a ‘black swan event’, which unfolds as a surprise but would be unfairly rationalised with hindsight.
What would happen if the dam collapsed?
The failure of China’s megastructure, which consists of enough steel to build more than 60 Eiffel Towers, would mirror Chernobyl proportions.
Theoretically, an ensuing tsunami will desolate millions of acres of farmland, leading to a potential famine right before the autumn harvest.
Not only that, the densely-populated cities hugging the banks of the Yangtze are likely to be rendered uninhabitable, killing millions.
Nicole Metje, the Professor of Infrastructure Monitoring and Director of the National Buried Infrastructure Facility at the University of Birmingham, tells LADbible that there would be long lasting environmental damage if a flood was to happen.
Sedimentation washout
“There are very obvious things that happen. They clearly range from severe flooding downstream, and with the volume of water held back by the Three Gorges Dam, that will be significant. It will change the whole flora and fauna,” Professor Metje said.
“It’s not just something that’s going to flood. When the flood recedes, it’s all going to be fine and just grow again. There’s quite a lot of issues often with sedimentation washout.”
She adds: “You’re actually changing the nature of the material as well. You probably have a lot of sludge, a lot of sedimentation, which you then build up. So even when the water disappears, there’s probably still a lot of most likely unusable area in the short term, which is exactly what we’re seeing in Ukraine. That’s a risk to the area, but it’s clearly a risk to infrastructure, to people, so a threat to life.”
Upstream impact
Professor Metje notes that there would be ‘a significant impact upstream as well’.
“So not just downstream you’ve got the flood, but obviously the water will recede upstream very quickly,” she explains.
“That will again have issues on livelihoods and how people use the area because, when the dam was first built, there were a lot of villages in what is now flooded by the water.
“The water will recede and, therefore, the environment and the cultural setup will all change because you suddenly go from having several metres of water to having very little water.”
Threat to life and water supplies
“Finally, it has a significant impact on drinking water because it is actually a water reservoir, so people use it for drinking water. If you lose that, that has a significant impact,” she adds.
“There are some short-term impacts – the flooding, the risk to life, to infrastructure, to livestock and wildlife – that are immediate if it were to fail like this. Then there’s the long term, so it’s not just like a flood happened and then it dries.”
“We see this even if we have river flooding. Even when the water recedes and you dry out, you’ve got all the water in the buildings. It’s a long-term issue.”
Why a collapse is unlikely
The expert stressed that a catastrophic collapse is highly unlikely, explaining that the Three Gorges Dam is a modern concrete structure designed to withstand immense pressure and is continuously monitored for structural issues.
While no dam is entirely risk-free, she said failures are more commonly associated with earth dams than concrete dams of this type.
If problems were to develop, they would most likely stem from issues beneath the foundations, where seepage and erosion could undermine the structure, rather than the concrete wall itself failing naturally.
Slowing down the Earth’s rotation
Natural disasters are child’s play for the Three Gorges Dam, though, because this absolute beast is literally slowing down our planet’s rotation, too.
In 2005, NASA’s Dr. Benjamin Fong Chao calculated that, when full to capacity, the dam increases the length of an Earthbound day by 0.06 microseconds.
Chao also reckoned that the dam moves the two poles of the Earth by around two centimetres.
This is all down to a phenomenon known as the ‘moment of inertia’, with the Three Gorges resisting the Earth’s spin.
The Three Gorges Dam sits 185m above sea level at its highest point, so when its waters are teetering on bursting, both the local mass and the distance of that mass from our rotational line increases.
Moment of inertia goes up, creating a resistance (although extremely small) to Earth’s spin.
Additional words by Anish Vij.
