Siang Upper Multipurpose Project: Displacement Fears, Public Consultation and the Brahmaputra Question
The proposed Siang Upper Multipurpose Project (SUMP), a very large dam on the Siang river in Arunachal Pradesh, is again at the centre of public debate.
The project has caused worry among the indigenous Adi community, who live in the Siang valley. Their main fears are displacement (being forced to leave their homes and land), loss of farmland and forests, and damage to the river's ecology.
Opposition groups in the state have demanded that the project should not go ahead without proper public consultation with the affected people.
The project is still at an early stage. Work on the pre-feasibility report (a first study of whether the dam is technically possible) has faced resistance in several villages, and no final decision to build the dam has been taken.
The Union and state governments present the dam mainly as a water storage and flood-safety project, meant to protect India against sudden water releases from China's giant dam upstream on the same river.
Siang Upper Multipurpose Project (SUMP): India's Storage Dam on the Siang
The Siang Upper Multipurpose Project is a very large dam proposed on the Siang river in the Upper Siang and Siang districts of Arunachal Pradesh. The Siang is the name of the Brahmaputra when it first enters India from Tibet. "Multipurpose" means the dam is planned to do several jobs at once: store water, reduce flood risk, keep the river flowing in the dry season, and produce electricity.
The latest debate is about whether the SUMP should move ahead without the full support of the local people. The demand for public consultation shows the clash between the national security and flood-safety case for the dam and the land, livelihood and culture of the communities who would lose their homes.
Adi Tribe of Arunachal Pradesh
The Adi are one of the largest tribal communities of Arunachal Pradesh. They live mainly in the valleys of the Siang river and its tributaries, in districts such as East Siang, Upper Siang, Siang and West Siang. They speak languages of the Tani group, part of the larger Tibeto-Burman family. Their life, farming, festivals and beliefs are closely tied to the Siang river and its forests.
The Adi are the people most directly affected by the SUMP, because the reservoir would flood parts of their homeland in the Siang valley. Their fears about displacement and their demand to be properly consulted are at the heart of the current debate.
Environmental Impact Assessment (EIA) Notification, 2006
The Environmental Impact Assessment (EIA) Notification, 2006 is the main rulebook that decides whether a big project in India can be built. It says that large projects like dams, mines and power plants must get an environmental clearance before work starts. To get it, the project must study its likely effects on nature and people, and must hold a public hearing where local people can raise their concerns.
The demand for public consultation on the SUMP points to the EIA's public hearing stage and to the wider idea that affected people must be heard before a mega dam is approved. Because the project is still at the pre-feasibility stage, the formal EIA public hearing has not yet taken place.
- SUMP: on the Siang (the Brahmaputra's name on entering India), Upper Siang and Siang districts, Arunachal Pradesh
- Planned capacity: about 11,000 to 11,200 MW; planned live storage about 9.2 billion cubic metres
- Proposed executing agency: NHPC Limited
- China's Medog (Yarlung Tsangpo) project: about 60,000 MW, construction began July 2025, estimated cost about 1.2 trillion yuan
- Adi: Scheduled Tribe of Arunachal Pradesh; Tani languages (Tibeto-Burman family); Kebang village council; Solung festival
- EIA Notification 2006: under the Environment (Protection) Act, 1986; hydro projects of 50 MW or more are Category A