The Three Gorges Dam is currently the largest hydropower complex built worldwide, its main objective was to generate electric power and manage the floods of the Yangtze River. However, as construction work commenced in 1994, some of the targets set for the dam have already been realized. Nevertheless, it has been contentious and faced challenges experienced by many projects such as ineffective flooding control.
Three Gorges Dam of China: A technological wonder but with little impact on flooding
Constructed in the year, the 2006 181 m high and 2,335 m long dam on the Yangtze River has a hydropower plant that has been operational since 2012 with a generating capacity of 22,500 megawatts, which makes it among the largest in the world.
At the beginning, the purpose of the dam was to reduce the damaging effects of floods, which was recurrent problem in the valleys of the Yangtze River, millions of people and properties were lost due to rare but great flooding.
It was anticipated that by constructing the barrier, downstream settlements would be spared from an overdue flooding of once in a hundred years. This expectation however has not been fulfilled completely. The storage capacity of the dam reservoir is approximately 22 billion cubic meters, which is not commensurate with the amount of water that is required during the extreme season of flooding.
To illustrate, a typical one in hundred years flood for the countless Chongquing designs would aim a flow of around 244 billion cumec at the Yangze, which is beyond the capability of the dam. According to some experts on rocks and earths, only 9% of such flood volume can be accommodated, thus making the dam less useful for flood fighting efforts.
2020 inundations revealed boundaries to the extent to which the Three Gorges Dam can manage the Yangtze River
In addition, the flood control season of 2020 drew attention to the weak points of the dam in terms of controlling floods. Areas affected by heavy rainfall experienced rising water levels which broke records causing geographical, economic and social disruption, forceful dislocation of people and even death.
Under such situations, the dam was referred to as the most important factor in reducing the levels of floods by the authorities but even that turned out to be wrong since it was flooded record levels of water even at the places behind the dam.
There are many who maintain that it is not only overly optimistic, but entirely bizarre, to hope for the regulation of the outflow of one of the largest rivers on the planet, the Yangtze, by a single structure. The dam however has had adverse effects not only on flood control, but on social as well as environmental issues.
Approximately 1.4 million inhabitants were forced to undergo displacement, and this entailed the abandonment of their homes, farms and villages. Several people who were relocated from the declared area noted that after the resettlement their earnings diminished and even there have been cases considering misappropriation of relocation’s funds.
The studies have revealed a connection between landslides and the potential for increased seismic activity in the vicinity of the Three Gorges Dam
Negative impacts on the environment are associated with the dam due to the rise and fall of the water level in the reservoir leading to the erosion of riverbank and consequently landslides as well as the pressure of the dam being associated with the rise in earthquakes.
Research projects have indicated an increase in earthquake occurrences due to the issue of water seeping into the fault lines within the area that is active tectonically. Even political manipulations did not save the project; the Chinese leadership took a long term strategic decision to build dams on Yangtze River but for quite some time there was social and political resistance to it.
After the violent 1989 Tiananmen protests, the regime sought to have it approved by the National People’s Congress despite stiff opposition from the public. Finally, the Three Gorges Dam is epitome of engineering might in China but also exposes the difficulties in curbing one’s technological dreams to embrace nature. Although it has increased the energy generation capacity.
The limited flood mitigation benefits and environmental implications of such projects are more complex than what mega-projects at such great scale seem to imply, and the Chinese government is in the process of grappling with mitigating them.
