In the last week of October, India deployed more than 2,500 security personnel, including central armed forces, to Arunachal Pradesh. The region is a China-bordering state in the eastern Himalayas, where Beijing claims approximately 90,000 square kilometers of territory.

This development closely followed statements from a senior official in the Indo-Tibetan Border Police, the force responsible for guarding the China-India border, who reported that face-offs between Indian and Chinese forces are occurring “at several locations in Arunachal and it still continues.” However, officials clarified that the increased force mobilization in Arunachal was unrelated to the ongoing border tension.

While alleged Chinese incursions into Indian territories have been raising concerns among civil society groups in Arunachal Pradesh for several months, another part of the state bordering China is experiencing heightened tensions due to local opposition to a mega hydropower project. India views the project as critical to counter China's control over a major transboundary river.

Locals belonging to the Adi and Galo tribes had called for a peaceful shutdown on October 23 to protest the administration’s decision to move ahead with the mega dam on the river Siang despite local opposition.

However, with police using tear gas to disperse the protesters, the demonstration turned violent in several places.

During the unrest, a police station, several government offices, and the homes of multiple leaders belonging to Prime Minister Narendra Modi’s Bharatiya Janata Party (BJP) were vandalized. The BJP currently leads coalition governments both at the national level in the center and in the state of Arunachal Pradesh.

The authorities have slapped a series of police cases against key protest organizers. [caption id=attachment_317823 align=aligncenter width=1217] A screenshot of an Arunachal Today video showing people protesting against the Siang dam project and demanding the release of all arrested persons, Itanagar, Arunachal Pradesh, India, Oct. 29, 2026.[/caption] The dam at the heart of the ongoing protests is the Upper Siang Multipurpose Storage Project, an 11,200-MW hydropower and water-storage project that India plans to build on the Siang River in Arunachal’s Upper Siang district.

The Siang River originates in China’s Tibet region, where it is known as the Yarlung Tsangpo.

Beijing is constructing a massive 60,000-megawatt hydropower project on this same river at Medog, situated just before the waterway enters Arunachal Pradesh, where it is known as the Siang.

The river then flows through Assam as the Brahmaputra and crosses into Bangladesh before emptying its waters into the Bay of Bengal.

Resistance in Arunachal Pradesh to the Siang hydropower project is not new, with objections to the development having been raised for over four years.

In recent months, the federal and state governments and BJP leaders have repeatedly highlighted the project as being of national interest because it would help regulate water flow in the Siang River.

Yet, the protests have now flared up right at a time when border skirmishes with Chinese forces are triggering border security concerns.

This has left Arunachal Pradesh, India’s easternmost state, faced with multidimensional security challenges.

Indian authorities have presented the Siang project as important not only from the perspective of water and energy security and flood moderation, but also as a strategic response to China’s upstream hydropower ambitions.

The government has maintained that decisions would be taken only after assessing the project’s feasibility.

However, members of the local Adi indigenous group have been opposing the project over the potential submergence of ancestral land, displacement, and environmental risks.

Instances of dam breaches caused by glacial lake outburst floods, including the catastrophic event in Sikkim in 2023, have intensified their anxieties.

The latest trigger was the beginning of the pre-feasibility report (PFR) survey.

In September, the Arunachal Pradesh Cabinet approved the formation of a high-level committee designed to coordinate survey-related activities and facilitate engagement with local residents.

Headed by Rural Development Minister Ojing Tasing, the delegation included two local Bharatiya Janata Party (BJP) legislators, Alo Libang and Oni Panyang.

The pre-feasibility survey assesses technical feasibility, hydrology, geology, and broad impacts.

If the report deems the project feasible, the government will subsequently have to initiate steps to prepare a Detailed Project Report (DPR), secure environmental and forest clearances, and conduct a social impact assessment and public hearings.

The Siang Indigenous Farmers’ Forum and other local organizations have objected to pre-feasibility survey activities, which include drilling.

They demand prior and informed consent from the locals even for initiating pre-feasibility activities.

They estimate that 27 villages could be completely submerged if the dam is constructed, with many displaced.

For members of the Adi tribal group, ancestral land, farming, river-dependent livelihoods, and traditional relationships with the Siang are inseparable.

That is why they oppose relocating and letting go of their ancestral land.

Even their cosmology and belief systems are linked with their land, forests, and rivers, they say.

A mega-dam would irreversibly alter their landscape, economy, and cultural continuity.

Besides, the region itself is ecologically and geologically fragile. "The deployment of security personnel to facilitate surveys has deepened mistrust rather than resolved these concerns," alleged Ebo Mili, an Adi lawyer, who is one of the most prominent faces of the protests.

The police have slapped him with multiple charges of violence and conspiracy related to the protests.

On October 13, protesters submitted a memorandum-cum-ultimatum to the administration, expressing concerns over alleged administrative and police excesses against villagers who were protesting against PFR activities.

Unsatisfied with the administrative response, several groups—including the Adi Baane Kebang United (ABKU), the Siang Indigenous Farmers’ Forum (SIFF) youth wing, the Siang Upper Multipurpose Project Affected Area Youth Association, and the Adi Galo Welfare Society—called a 12-hour shutdown across the districts of Siang, Upper Siang, and East Siang on October 23. During the shutdown, violence erupted at numerous locations.

The residence of local legislator Oni Panyang, who was entrusted with coordinating PFR activities, was vandalized, while some police vehicles and government offices were torched.

More police cases and arrests under anti-terror laws followed.

As of October 30, tension prevails in the villages around the dam’s possible location.

Whether the project is an appropriate response to the Chinese dam will likely continue to be debated.

Many of the locals don’t want any dams.

They state that the Chinese project would not significantly hinder the flow of the Siang River, noting that the river's primary water source originates downstream from the proposed location of the Chinese dam.

However, another question is also becoming important: whether a project justified partly on national security grounds can proceed without the confidence and meaningful participation of the communities expected to bear its costs.

Why it matters

The development of the Upper Siang hydropower project carries transboundary water implications for downstream nations while testing the limits of infrastructure projects pursued on national security grounds against local indigenous resistance.