Written by, Aug. 31 -- Pooja Gupta

The Siang Upper Multipurpose Project (SUMP), proposed in Upper Siang district in Arunachal Pradesh, is set to be India's largest hydropower dam - a nearly 11,000 MW structure conceived to regulate the flow of the Siang River, which becomes the Brahmaputra downstream in Assam. It is also one of the most intriguing questions facing the Northeast today because it sits at the meeting point of three legitimate concerns that do not easily resolve into one another: national water security, the wellbeing of the Adi and Galo communities who call this valley home, and India's strategic position vis-a-vis China's upstream dam-building on the Yarlung Tsangpo.

The case for SUMP begins upstream, in Tibet. China star...