Why China’s Mega Dam In Tibet Is So Controversial

China has started construction of the world’s biggest hydroelectric dam, a project that’s set to be far larger than the Three Gorges Dam — already the world’s biggest single source of green power — and more expensive than the International Space Station.

The colossal undertaking in the mountainous region of Tibet is set to cost around 1.2 trillion yuan ($167 billion), could take at least a decade to complete and would boost China’s output of clean energy. It will also stir controversy over the potential impact on the local environment, and could further strain relations with its downstream neighbor, India.