7.3 Magnitude Earthquake Strikes Three Gorges Dam, Left 1,543 Houses Severely Da.mp4

7.3 Magnitude Earthquake Strikes Three Gorges Dam, Left 1,543 Houses Severely Damaged
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True Around World
Published on 20 Jul 2021
Strong 7.3 magnitude earthquake strikes Three Gorges Dam region. A 7.3 -magnitude earthquake struck a mountainous and populous area of China’s Hubei Province today, 100 kilometres from the Three Gorges Dam site. Officials have been quick to reassure the public that the dam has remained intact and is operating normally after the event, which occurred at 1:04 p.m. in Enshi Tujia and Miao Autonomous Prefecture, Badong County. Aftershocks and quake-triggered landslides are expected. A strangely well-timed report entitled “Experts hail Three Gorges project, deny link to disasters,” published two days before today’s earthquake by China’s state-run Xinhua news agency, strived at length to counter concerns the country’s Three Gorges Dam might be the cause of alarming impacts, such as earthquakes, as a result of its operations; an article likely prompted by growing fears regarding large dams in seismic-prone areas, which has generated a fair amount of media interest in China this year. Emphasizing the successful operation of the controversial Three Gorges Dam for the past decade, Xinhua News quotes Gao Anze*, a former chief engineer with the Ministry of Water Resources, who says, “it is normal to have different views on such a massive project,” and that accusations of the project’s negative environmental and climate impact, and its role as a trigger for geological disasters and even earthquakes, did “not have scientific basis and will not help nurture objective evaluations on the impacts of the Three Gorges project.” But fears are justified and, contrary to Gao Anze’s claim, they do have a scientific basis. A 2021 Chinese study by seismologists at the China Earthquake Administration, a government agency, found that the massive Three Gorges Dam — which sits atop two major fault lines, the Jiuwanxi and the Zigui-Badong — had triggered around 3,000 earthquakes and numerous landslides in the dam’s reservoir (in the six years after inundation began in 2003), representing a 30-fold increase over pre-dam seismic activity in the area. The study concluded that the Three Gorges Dam on the Yangtze River had “significantly increased” seismic activity along the dam’s reservoir and also helped to explain a spate of landslides that have caused havoc in the region. Man-made dam reservoirs, particularly large reservoirs built on fault lines where a vast amount of water would add substantial pressure to any existing fractures, prompted alarm in China’s southwestern Sichuan Province earlier this year in April when a magnitude-7 earthquake struck Lushan County in Ya’an City. Some experts believe the April quake may have been an aftershock of Sichuan’s major 2008 earthquake disaster, which they argue may have been triggered by the Zipingpu Dam reservoir – due to a phenomenon known as “Reservoir-induced Seismicity (RIS).” Scientists have observed that reservoir impoundment (the filling of the reservoir) may not only increase the risk of strong earthquakes, especially in areas already vulnerable to high-intensity seismic activity, but may represent a more pronounced risk in the first few years after a dam is filled. [See also Did the Zipingpu Dam Trigger China’s 2008 Earthquake? The Scientific Case].