A glacial lake formed by a landslide on the Yarlung Zangbo River in Tibet is proving to be an obstacle for China’s mission to build a major hydropower plant on the river’s lower reaches close to the border with the Indian state of Arunachal Pradesh.
Last month, the central government in China had given its go-ahead to the construction of a dam and hydropower plant on the lower reaches of the river in the Tibet Autonomous Region (TAR). The mission had been included in the country’s 14th five-year plan.
The hydropower project is expected to have an electricity generation capacity of 70 gigawatts, which is nearly three times that of the Three Gorges Dam on the Yangtze River.
Rising in Tibet, the Yarlung Zangbo flows into Arunachal Pradesh as Siang, and then as Brahmaputra in Assam before flowing into Bangladesh.
The project has run into a recently-formed and unstable mountain lake with some 600 million cubic metres of water, the Hong Kong-based South China Morning Post (SCMP) reported on Wednesday.
The lake was formed in 2018 following a landslide caused by a melting glacier in the Sedongpu Basin in eastern TAR’s Milin County.
“With the river spilling over the top at present, the dam could collapse at any time,” the SCMP report said. The lake in the Sedongpu Basin “sits just a few dozen kilometres upstream from the planned construction site of the super hydropower plant. With so much water hanging overhead, no construction workers can move in to clear the ground”.
“The situation is very difficult. There is not any immediate solution yet,” said Xing Aiguo, a professor of civil engineering at Shanghai Jiao Tong University who was involved in one of the studies to look into possible solutions.
The climate crisis makes the region prone to similar disasters.
“The development and utilisation of natural resources and energy in the Yarlung Tsangpo River must fully consider the situation of avalanches and debris flows in the Sedongpu valley,” Liu Chuanzheng, a government researcher with the Consultative Centre of Geohazard Mitigation under the natural resources ministry in Beijing, wrote in an official report on the landslide published in the journal Geology in China, 2019.
At present, scientists and experts are trying to find a solution to the problem.
With Arunachal Pradesh being a lower riparian state and with the possibility of the project’s impact on water security in India’s northeastern states, New Delhi would be closely following the developments around the hydropower plant.