China builds the world's largest dam, and India checks every drop

China has begun constructing the Medog hydropower station in Tibet, set to be the world's largest with an annual output of about 300 billion kWh. India opposes the project due to fears of Chinese control over the river flow into its territory, and in response is accelerating the construction of its own dam.

China has begun building the Medog hydropower station in Tibet, which is expected to be the world's largest. Premier Li Qiang announced the project in July 2025, and construction is expected to take about a decade. The dam will be built where the Yarlung Tsangpo River drops 2,000 meters over 50 kilometers, and five stations are expected to generate about 300 billion kWh per year—more than the entire annual electricity output of the UK. The estimated cost is 1.2 trillion yuan, about $167 billion. India opposes the project due to fears of Chinese control over the river flow into its territory. The Chief Minister of Arunachal Pradesh, Pema Khandu, called the dam a "ticking water bomb." China rejected the term and claimed the project is a sovereign matter. In response, India is accelerating the construction of the Upper Siang dam, which was previously delayed due to Chinese concerns about flooding. China stopped sharing river data with India in 2017, resumed sharing in 2018, and the memorandum of understanding expired in June 2023, after which sharing was halted again.