China’s Mega Dam in Tibet Raises Concerns Over Ecology, Livelihoods

The Project Threatens Ecology and Livelihoods in Tibet, India, Bangladesh

January 7, 2025

China is building the world’s largest dam on a major river in Tibet, which originates from a glacier in the northern Himalayas and flows downstream as the Brahmaputra River, crossing into India before merging with the Bay of Bengal through Bangladesh. The project is expected to significantly impact crucial ecosystems and the livelihoods of millions of people, including those in India and Bangladesh.

Originating from the Angsi Glacier, the Yarlung Tsangpo River (pronounced YAR-loong TSANG-po) serves as a vital lifeline in Tibet. Spanning 2,900 kilometres, the river flows eastward through the Tibetan Plateau, carving one of the world’s deepest gorges, the Tsangpo Grand Canyon. It then winds through Arunachal Pradesh and Assam before reaching Bangladesh, supporting diverse ecosystems and sustaining millions of people reliant on it for agriculture, fishing and daily life.

However, all of this is now at risk due to China’s plan to construct a colossal dam on the river.

The dam is poised to change the river’s course—literally and figuratively.

Designed to generate an astounding 300 billion kilowatt-hours of electricity annually—sufficient to power about 28 million homes for a year—the dam is certain to reshape the river’s natural flow and transform its surrounding landscape.

The Yarlung Tsangpo, as it flows into the Brahmaputra, is home to a rich variety of fish and aquatic life that rely on the river’s natural flow cycles for survival. Interrupting this rhythm could disrupt breeding and feeding patterns, leading to a loss of biodiversity.

A large reservoir created by the dam would submerge forests, agricultural land and habitats in Tibet, displacing both wildlife and local communities. Further, sediment vital for enriching downstream farmland in the fertile floodplains of the Brahmaputra River basin in India and Bangladesh would become trapped behind the dam, potentially reducing the fertility of agricultural plains where farmers rely on the river to sustain their crops.

For the people living near the river in Tibet, the consequences could be devastating. Entire villages in the region may need to be relocated to make way for the massive reservoir, uprooting families and severing ties to ancestral lands and cultural traditions.

Beyond this human toll, the dam’s reservoir would hold an enormous volume of water, exerting pressure on the Earth’s crust in the seismically active Tibetan Plateau. The Himalayas, with their dynamic tectonic plates, could face an increased risk of earthquakes, threatening communities not only near the dam site in Tibet but also in downstream areas, including parts of northeastern India and Bangladesh.

Downstream countries, particularly India and Bangladesh, are likely to feel the effects keenly. Controlling the river’s flow through the dam could reduce water availability during dry periods and worsen flooding during monsoons. Such changes could spell trouble for agriculture, drinking water supplies and fisheries in regions that depend on the Brahmaputra. Further, the dam’s disruption of sediment flow could accelerate erosion along riverbanks and cause delta regions in Bangladesh to sink faster, leaving these low-lying areas more vulnerable to rising sea levels.

Beijing must recognise that the Yarlung Tsangpo-Brahmaputra, as a transboundary river, is a shared resource for Tibet, India and Bangladesh. China’s control over its upper reaches has been a longstanding source of tension. Constructing this dam without consulting downstream nations risks being perceived as a unilateral attempt to control water resources critical to their populations. Such move could heighten fears of water being used as a political tool.

International frameworks, like the UN Watercourses Convention, adopted in 1997, encourages countries sharing a river to use its waters fairly and sustainably, so that no nation takes actions that harm others, especially when it comes to altering a shared watercourse.

However, some nations, including China, have not agreed to the convention’s principles, limiting its potential to mediate disputes or enforce cooperative practices.