China formally began construction of a massive dam on the Brahmaputra river close to the border with Arunachal Pradesh at a ceremony that was attended by Premier Li Qiang last week, Xinhua reported.The $167.8 billion hydropower project, which will be the world’s largest when it is completed, has been talked about for long, and has raised concerns in India and Bangladesh about the impact it may have on the flow of the river.Concerns in ArunachalThe dam on the Yarlung Zangbo (or Tsangpo), as the Brahmaputra is known in Tibet, is being built at the “Great Bend”, where the river makes a U-turn in Medog county before entering India at Gelling in Arunachal Pradesh. The river is called Siang in Arunachal Pradesh.Ritesh KumarThe dam, which China announced in 2021, will have a generation capacity of 60,000 MW, three times that of the Three Gorges Dam on the Yangtze, which is currently the world’s biggest hydropower station.In an interview given to PTI about a week before the dam’s groundbreaking ceremony on July 19, the Chief Minister of Arunachal Pradesh, Pema Khandu, described it as a potential “water bomb” and an “existential threat”.“Setting aside the military threat from China, it seems to me that this is a far bigger issue than anything else. It is going to cause an existential threat to our tribes and our livelihoods. It is quite serious because China could even use this as a sort of water bomb,” Khandu said.The Chief Minister said “no one knows what [China] might do”, and if “they suddenly release water, our entire Siang belt would be destroyed”. He expressed apprehension that “in the long run…our Siang and Brahmaputra rivers could dry up considerably”.Story continues below this adOther experts too have flagged the risk of flooding due to the intentional or unintentional operation of reservoirs in Tibet, as well as unforeseen events such as dam failure, landslides, or earthquakes.Tibet is a seismically active zone where the Indian tectonic plate collides with the Eurasian plate, and the region where the dam is coming up is considered to be earthquake-prone and ecologically extremely fragile.The view from AssamThe Brahmaputra is the lifeline of Assam, fundamental to its economy, and central to its history, culture, and ecology. Any significant disruption in the flow of the river in the state will have far-reaching consequences.On July 21, Assam Chief Minister Himanta Biswa Sarma sought to alleviate concerns, pointing out that the Brahmaputra grows into a mighty stream only in Assam, fed by numerous tributaries and bountiful monsoon rain.Story continues below this adAlso Read | Why China is building the world’s largest dam on the Tsangpo, how India may be impacted“I am not immediately worried because Brahmaputra is a mighty river and it is not dependent on a single source [of water],” Sarma said. “Brahmaputra gets most of its waters from Bhutan, Arunachal Pradesh, and the rainwater and other forms of water from our state itself,” he said.Earlier on June 2, the Chief Minister had posted on X that “the Brahmaputra is not a river India depends on upstream”, and that “China contributes only ~30-35% of the Brahmaputra’s total flow — mostly through glacial melt and limited Tibetan rainfall”.But even in the unlikely event of China reducing water flow, “it may actually help India mitigate the annual floods in Assam, which displace lakhs and destroy livelihoods every year”, he had said.On July 21, however, Sarma said there were different theories on the potential impact of the dam, and he believed that the Centre “must already be having a discussion with China, or will have a discussion [on this issue].”The Indian responseStory continues below this adIndia issued no official reaction after the July 19 ceremony. But New Delhi has said it is monitoring Chinese infrastructure interventions on the river.In January, Ministry of External Affairs spokesperson Randhir Jaiswal had said: “As a lower riparian state with established user rights to the waters of the river, we have consistently expressed…our views and concerns to the Chinese side over mega projects on rivers in their territory.“These have been reiterated, along with the need for transparency and consultation with downstream countries, following the latest report [on the Medog county project]. The Chinese side has been urged to ensure that the interests of downstream states of the Brahmaputra are not harmed by activities in upstream areas.”China Tracker | China This Week | Limited results from EU-China summit, India’s visa resumption, and the Chinese mega damOn July 23, Guo Jiakin, spokesperson for the Chinese Foreign Ministry, told reporters that the project was “fully within China’s sovereignty”.Story continues below this ad“China is engaged in cooperation with downstream countries on sharing hydrological data, flood prevention and disaster reduction,” he said, adding that Beijing has had the “necessary communication” with both India and Bangladesh.Ashok Kantha, a former Indian Ambassador to China, had told The Indian Express earlier that the project, with its “very large reservoir, in a very difficult area” was “very risky, dangerous, and irresponsible”. India, Kantha had said, needed to raise its concerns with China “forcefully”.India is currently engaged with China in a series of confidence-building measures after Foreign Secretary Vikram Misri announced last October that the two sides had reached an agreement “on patrolling arrangements along the Line of Actual Control, leading to disengagement and a resolution of the issues that had arisen in these areas in 2020”.During talks held in Beijing in March, the two sides “exchanged views on early resumption of cross-border cooperation and exchanges, including on trans-border rivers”, an official statement said.Story continues below this adOn July 23, India said that it would resume issuing tourist visas to Chinese nationals after a gap of five years. The annual Kailash Mansarovar Yatra, which had been on hold for the last five years, resumed on June 30.Mitigation measuresAt the heart of India’s concerns, as articulated by Chief Minister Khandu, lies the fear that China may seek to weaponise the dam project at some stage, perhaps to build pressure on behalf of Pakistan after India suspended the Indus Waters Treaty in the aftermath of the terror attack in Pahalgam in April.“There may not be reasons to be phobic about China’s move, even as India should be concerned,” Uttam Sinha, Senior Fellow at the Manohar Parrikar Institute for Defence Studies and Analyses in New Delhi, said.Express View | India, China and the Brahmaputra frontSinha said India should make scientific calculations about the Chinese dam project, and build its own capability and capacity to preempt any deliberate actions in the future.Story continues below this adWater experts Naresh K Mathur and Debarshee Dasgupta had written in The Indian Express earlier that as a mitigation strategy, India could plan storage on rivers of the Brahmaputra system to absorb potential variations in flows (periods of flooding and reduced flows).The Upper Siang project in Arunachal Pradesh, with its 300-metre-high dam, is seen as important not just for its formidable hydropower potential, but also as a strategic imperative in view of the Chinese projects in Tibet. The dam’s storage can serve as a buffer against variations in the flow of the river.However, progress on the project has been slowed by local resistance against the potential adverse environmental impact of the dam.Sinha said there is a need to build more inland channels to carry the flow of excess water in the future. The National Water Development Authority has proposed two links to connect the Brahmaputra and its tributaries to the Ganga basin with the aim of transferring surplus water to water-scarce regions.Story continues below this adExperts have also stressed on the need to utilise diplomatic channels to seek detailed hydrological and project-related data from China in order to assess downstream impacts on a continuous basis.India should also have conversations with other low riparian neighbours — Bhutan, Bangladesh and even Myanmar — on developing a coordinated protocol for advance warning and disaster preparedness.