BEIJING: A 510MW Chinese hydroelectric dam became operational on the Brahmaputra on Tuesday. Official Xinhua news agency said electricity from all units of the Zangmu Hydropower Project in Tibet, regarded as the highest in the world and just 550km from the Indian border, had been connected to China's national power grid.While an Indian official said the government wasn't concerned as China has assured India it was a run-of-the-river project, visiting Indian ministers and officials have repeatedly expressed unease over dams on the Brahmaputra. India's discomfort emanates from the possible impact on Upper Siang and Lower Subansiri projects in Arunachal Pradesh if the dam in Tibet reduces the Brahmaputra water flow.Also, while Indian officials said China has assured this dam will have little impact on environment or water flow downstream, the project has turned out to be massive: the dam, 390m long and 116m high in Gyaca County of Shannan Prefecture in Tibet, will generate 2,500MW once it is completed."As if to underscore the contrast between an autocracy and a democracy, China's announcement that Tibet's largest dam project is fully operational coincided with protesters stalling Lower Subansiri, India's sole large dam project under construction," said Brahma Chellaney, professor of strategic studies at the New Delhi-based Centre for Policy Research."China is now racing to complete five other dam projects on the Brahmaputra. China's frenzied dam building on the Brahmaputra and other Tibetan rivers flowing to India is a reminder that Tibet remains the core issue in Sino-Indian relations," Chellaney said.Observers believe Zangmu Hydropower Project's completion reflects India's failure to persuade China to reduce its size in view of flooding dangers it poses to downstream areas. "India needs to be very vigilant about Chinese interventions on (the Tsangpo/Brahmaputra),'' former water resources secretary Ramaswamy R Iyer had told TOI in 2014, adding, "Run-of-the-river projects are slowly being recognized as a seriously harmful set of interventions.''He had also said adjustment of river flows to the intermittently operational turbines creates huge variations on a daily basis in downstream flows, which could have a devastating impact on aquatic life and displace riparian populations.An Indian inter-ministerial expert group (IMEG) had advised the government in 2013 to intensify monitoring of river flows from upper to lower reaches of Brahmaputra in view of dangers posed by this dam. IMEG had noted three dams, Jiexu, Zangmu and Jiacha, were within 25km of each other and just 550km from the Indian border.China had agreed in 2013 to provide more flood data of the Brahmaputra from May to October instead of June to October as per river waters agreements. China is building two other dams on the Yarlung Zangbo River, the Chinese name for Brahmaputra. These dams, 510 MW Gyatsa and 360 MW Zhongda, are in different stages of construction. Two more dams, Jiexu and Langzhen, are still on the drawing board.