GUWAHATI, Dec 25 - The reports of formation of three artificial, landslide-induced dams on the Yarlung Tsangpo (Brahmaputra), containing an accumulated water of around one billion cubic metres, have raised alarm bells here. Experts here have called for immediate measures to channel out the waters of these dams. The dams were formed following the November 17, 2017 earthquake of 6.4 magnitude that shook the Nyingchi County of Tibet.The study of the December 10, 2017 satellite imagery captured by the European Space Agency’s Sentinel -2 undertaken by research scholars Chintan Sheth of the Bengaluru-based National Centre for Biological Research (NCBR) and Anirban Datta-Ray of the Ashoka Trust for Research in Ecology and the Environment (ATREE) has found that three dams were formed on the Yarlung Tsangpo in the Bayi district of Nyingchi county of Tibet.
The three dams, result of a massive landslide triggered by the November 17, 2017 earthquake of 6.4 magnitude, are also found to be responsible for the Brahmaputra water turning turbid, said the researchers.
Noted Brahmaputra expert Prof JN Sarma of Dibrugarh University said that the area where this development has taken place is in an inaccessible deep gorge. He reminded that on June 30, 2000, 30 people died and all the bridges were washed away in a vast area of Arunachal Pradesh and Pasighat town was under three metres of floodwater due to the breach in the landslide-induced dam in Yigong area of Tibet.
The Government of India should take up the matter with China in due earnest so that this accumulated water could be released in a controlled manner, much ahead of the arrival of the monsoon season, he said.
“There should also be a move to remove the debris that have blocked the river and the original course of the river is restored,” he said, adding, mutual understanding and cooperation should be there among the basin countries like China, India and Bangladesh having trans-boundary rivers.
Another leading Brahmaputra expert Prof Dulal Goswami of Gauhati University said Delhi should immediately take up the matter with the Chinese authorities for taking appropriate measures like breaching the dams to discharge the accumulated water in a controlled manner as early as possible before the dams emerge as real threats to the society, ecology and infrastructure in downstream areas.
“This should be done keeping in mind the lessons learnt from the catastrophe caused by the breach of similar landslide-induced structures in 2000 in the Yarlung Tsangpo, which caused extreme sufferings for the people in Arunachal Pradesh,” he said.
In case of trans-boundary rivers of the size of the Brahmaputra, leveraging them for political gains will be extremely unfortunate, he said. The sooner a suitable mechanism involving all the basin countries, including China, is set up to address such exigencies, the better it will be for all concerned, said Prof Goswami.
Former Secretary, Water Resources Department, Assam, Nomal Chandra Das said the Government of India should take up the issue with China to release the accumulated water of the three dams by excavating canals along the dams starting from downstream so that the accumulated water comes down without causing any havoc. The debris deposited by the landslides in the river should be excavated and the materials should be removed to safer places so that they do not find their way to the river again.
Delhi should join hands with the Chinese authorities in monitoring the health of the Brahmaputra river so that such incidents can never recur, he said, adding, it is high time that the government takes initiative to constitute an international committee involving the riparian countries for monitoring the trans-national river.
It is worth mentioning that under a similar situation, the Subansiri river caused a catastrophe, following breach of a landslide-induced dam in the 1970s. The river earlier caused a massive catastrophe following the 1950 earthquake under a similar condition. In 2004, a breach in a similar landslide-induced dam in Kurishu river in Bhutan changed the course of Manas river leading to devastating floods in the lower Assam areas.