China’s Zangmu Dam on Brahmputra River: Concerns and Response of India

China’s Zangmu Dam on Brahmputra River: Concerns and Response of India

Written by: Dr. Reeta Kumari

Researcher, China Desk, Swadeshi Shodh Sansthan

Abstract

China has announced a mega dam project contructing on the Brahmputra river which is known as Yarlung Tsangpo (Tibtean name for Brahmputra river). China’s decision to construct a massive hydropower project on the Brahmaputra River in Tibet has generated deep strategic and environmental anxieties in India. The dam, projected to be the world’s largest of its kind, is situated near the Great Bend before the river enters Arunachal Pradesh. For India, the implications are multifaceted. First, there are ecological concerns, as unilateral upstream interventions could disrupt river flow, affect agriculture, fisheries, and groundwater recharge in the Brahmaputra basin. Second, the project raises geopolitical tensions, as it symbolizes Beijing’s growing leverage over transboundary water resources in South Asia, where no binding treaty governs the sharing of these waters. Finally, the dam adds a new layer to the already complex Sino-Indian relationship, intertwining water security with border disputes and strategic competition. While China frames the project as part of its renewable energy ambitions, India views it through the prism of vulnerability and asymmetry, underscoring the urgent need for regional water governance frameworks and confidence-building measures.

Keywords: India, China, Super dam, Brahmputra river, security challenges, border disputes, water security, ecological concerns, strategic competition.

Introduction

In November 2020, Beijing plans to build a massive “super hydropower dam” in Tibet, on the stretch of the Brahmaputra River close to India. A few months later, in March 2021, China’s National People’s Congress (NPC) approved the 14th Five-Year Plan (2021-2025), which officially included the project as one of its major development goals. The plan outlined the construction of what is expected to become the world’s largest dam, located on the lower reaches of the Yarlung Tsangpo River in the Himalayan foothills. While the full details remain undisclosed, reports suggest that Power Construction Corporation of China (PowerChina), together with the Tibet Autonomous Region government, will build a 50-meter-high dam at Medog, near the Great Bend of the Brahmaputra and close to the Indian border. The project aims to generate around 60 gigawatts of electricity each year over three times the output of the Three Gorges Dam. India has reacted with deep concern to this announcement. New Delhi fears the potential impact on downstream water flows and has stated that it is considering building its own 10-gigawatt dam to counterbalance China’s mega project.

The Yarlung Tsangpo is among the world’s largest international river systems. Rising in the Qinghai-Tibet Plateau of southwestern China, it stretches nearly 2,900 kilometres through southern Tibet, cutting across the Himalayas before entering India via Arunachal Pradesh and Assam, where it takes the name Brahmaputra. Several of its tributaries originate in China, while others flow from Bhutan, and together they carry immense economic, social, and political importance for the region. Given that South Asia is one of the most underdeveloped parts of the globe, every riparian nation seeks to harness the Brahmaputra to advance national growth agendas and broader international objectives such as the UN Sustainable Development Goals (SDGs).

China has constructed more dams than any other nation, with a greater number of large-scale projects than the rest of the world combined. Recently, it formally confirmed the development of what is set to be the largest dam in human history though satellite images suggest preparatory work began well before the project received official approval from China’s parliament in 2021. This colossal structure is being built on the Brahmaputra River, just before it crosses into India, in a geologically unstable and ecologically sensitive zone near the militarized border of Tibet and India. Once finished, the dam will surpass the scale of the Three Gorges Dam on the Yangtze, producing nearly three times more electricity by exploiting the river’s steep drop from the Himalayas into the planet’s deepest canyon.

However, the project is about much more than power generation. It poses the risk of severe environmental and geopolitical fallout threatening water security for millions downstream, destabilizing fragile Himalayan ecosystems, and giving Beijing an additional instrument of leverage against India, its regional rival. The lessons of the Three Gorges Dam seem lost on China. Once celebrated as an engineering triumph, it has since proven disastrous, accelerating riverbank erosion, damaging aquatic ecosystems, worsening water pollution, triggering landslides, and leaving behind lasting environmental harm. Alarmingly, the site of the new super-dam sits on a tectonic fault line. Experts caution that large reservoirs can induce earthquakes, a phenomenon called reservoir-triggered seismicity. In a region already prone to seismic activity, the stresses from such an enormous project could unleash devastating quakes.

Relations between China and India over shared river systems are particularly sensitive, with the Brahmaputra standing out as the most strategically significant. For both countries are home to the two largest populations on Earth and the river is a vital resource for their population. It provides India with almost one-third of its freshwater reserves and nearly 40 percent of its hydropower capacity. Although China does not rely heavily on the Brahmaputra for its overall water supply, the river is crucial for sustaining agriculture, energy, and livelihoods in Tibet. However, the growing demographic pressures in both nations are putting water availability under serious strain. Interestingly, even though a large part of the river basin lies within Chinese territory, Beijing’s contribution to the total discharge of the Brahmaputra is only about 22 to 30 percent.

Neighbours without Trust

For decades, rival water management and development strategies have fuelled mistrust and friction between India and China. A major flashpoint is Beijing’s push to build large hydropower and water diversion projects on the upper stretches of the Brahmaputra, which influence the river’s flow and course downstream. Since China controls the upstream portion, it holds a decisive advantage, with the ability to alter water availability for India it is something that has consistently raised New Delhi’s concerns. Although China maintains that these projects are solely aimed at producing electricity and will not diminish the volume of water flowing into India, Delhi remains unconvinced. In response, India has tried to assert its claim to prior usage rights and pressed for stronger monitoring frameworks to keep track of China’s river-related activities. These efforts, however, have had little success. At present, there is no comprehensive multilateral arrangement for cooperation between the two nations, only limited mechanisms.

India has long harboured doubts about China’s motives behind its dam-building on the Brahmaputra river. Many Indian experts believe that Beijing’s expanding hydropower projects and the intensifying contest over water resources could one day escalate into outright “water wars” between the two countries. Concerns are regularly voiced in India’s political circles, media, and government about the risks of relying on China for river flows. For instance, in 2013, Prime Minister Narendra Modi alleged that China was restricting the Brahmaputra’s waters. In 2017, the Siang River is a key tributary which suddenly turned black, rendering its waters undrinkable, harming the ecosystem, and disrupting farming in the region. Indian authorities pointed fingers at China, but Beijing dismissed the claims, stressing that its share of the river’s flow is relatively small.

Against this backdrop, China’s plan to construct a massive “super dam” has intensified India’s fears, reinforcing the perception that Beijing could eventually dominate the river and, by extension, the disputed borderlands. While Indian discourse frames this as a serious threat, Chinese state media has brushed off such claims as baseless. PowerChina, the state-owned company leading the effort, instead portrays the project as a “landmark opportunity” for China’s hydropower sector.

Since China contributes only a limited share to the Brahmaputra’s overall discharge, any effort on its part to modify the river’s flow would have little real effect on India’s water availability. This challenges the narrative of looming “water wars.” Still, instead of constructively engaging with India’s concerns, Beijing has largely responded with outright denials of any wrongdoing. Such dismissals tend to heighten, rather than ease, New Delhi’s anxieties, fuelling speculation about potential conflict. With no public access to detailed hydrological data or official project blueprints, it remains nearly impossible to assess the actual impact of China’s planned mega-dam. The lack of transparency only deepens India’s distrust.

This opacity indicates that India’s apprehensions cannot be written off as baseless. At the same time, responsibility for rising tensions does not lie solely with China. While Indian discourse often exaggerates the risk of future “water wars” and Chinese narratives play them down, the absence of a formal water-sharing treaty or a basin-wide cooperative framework leaves a dangerous gap. In this vacuum, Beijing’s dam project and the unresolved questions over Brahmaputra governance are fast emerging as another flashpoint in already strained Sino-Indian relations.

A river is more than just a source of water, it also transports nutrient-rich sediment that sustains ecosystems, farmland, and fisheries across vast regions. By placing a massive dam right before the Brahmaputra leaves Chinese-held territory, Beijing positions itself to regulate cross-border flows at will, particularly during the dry season. It could choose to release or withhold water, trap vital sediment, and even use the river as a political tool in future disputes. Blocking silt-heavy currents before they reach India and Bangladesh would deprive downstream plains of fertile deposits that enrich soil and support aquatic life. For Bangladesh, whose delta is already under siege from rising sea levels, this loss of sediment could accelerate land shrinkage, increase saltwater intrusion, and heighten the risk of devastating floods.

The project also threatens to disrupt the Brahmaputra’s natural flood cycle. Annual monsoon floods play an essential role in renewing farmland and maintaining ecological balance. Interfering with this seasonal pattern could wreak havoc on northeast India’s agriculture and imperil millions in Bangladesh who rely on the river’s ebb and flow. Beyond altering flood rhythms, the 168 billion dollars super-dam risks eroding riverbeds, degrading ecosystems, and hastening coastal retreat by trapping sediment and redirecting flows. In this way, China secures not only energy but also influence over the ecological and political futures of its neighbours. Its broader spree of dam construction on rivers originating in Tibet has already unsettled countries like Nepal, Vietnam, and Thailand. What sets this project apart is its unprecedented scale, its construction in a volatile seismic zone, and the clear strategic message it conveys.

For India, the dam is far more than a hydrological concern, it represents a potential instrument of coercion. In the event of renewed border confrontations, such as those seen during the clashes of 2020, Beijing’s upstream control could be wielded as leverage. This threat looms larger given China’s longstanding claim over Arunachal Pradesh, which it refers to as “South Tibet.” Ultimately, while hydropower production is the stated purpose, the true weight of this dam lies in the strategic dominance it affords China.

Despite the far-reaching risks, the global reaction has been largely subdued. India has expressed unease, but its official stance has remained restrained, reflecting the limited diplomatic and legal options it has to push back against China’s upstream dominance. Even so, New Delhi could attempt to spearhead efforts for international acknowledgment of Tibet as Asia’s critical “water tower” and advocate for enforceable rules governing cross-border river projects. China’s go-it-alone approach only fuels mistrust and accentuates the power imbalance in the region. Beijing has not signed any binding agreements on water-sharing with its neighbours, nor has it carried out credible environmental or seismic studies for a dam of this scale, despite the fact that it sits in one of the planet’s most earthquake-prone zones. The construction of the Brahmaputra super-dam therefore poses serious questions for regional peace and security.

The project reflects more than just an energy initiative; it embodies Beijing’s pursuit of “hydro-hegemony,” leveraging its position as an upstream power to extend geopolitical influence. In today’s world, where control over water is becoming as strategically significant as oil was in the last century, China is systematically positioning itself to wield immense leverage in the future.

Concerns for India

1. Water security

Water has emerged as one of the most critical strategic resources of the 21st century, and for India, the Brahmaputra River stands at the heart of this debate. China’s plan to construct a super dam on the Yarlung Tsangpo, as the Brahmaputra is known in Tibet, has triggered deep anxieties in New Delhi. Beyond the questions of energy and development, the project touches directly upon India’s water security, ecological stability, and long-term national interests. India fears that China’s control over the river upstream may allow it to regulate or even divert flows. During lean seasons, this could lead to reduced water availability for India’s northeast, harming agriculture and fisheries. Conversely, during floods, the sudden release of stored water could worsen flooding in Assam and neighbouring states. India’s major water concern is because the Northeast dependence is on the Brahmaputra, fear of reduced water flow, risk of sudden flooding, ecological disruption, strategic vulnerability etc.

2. Ecological damage

The Brahmaputra basin is a biodiversity hotspot. Altering its natural flow could threaten fragile ecosystems, displace riverine communities, and disrupt sediment patterns that are vital for soil fertility in Assam’s floodplains. For India, the fear is that altering the river’s natural rhythm will undermine the delicate environmental balance that has evolved over centuries. There will be disruption of sediment flow, impact on aquatic life, threats to forests and indigenous communities, landslides and seismic risks, climate change amplification etc.

3. Strategic and security dimensions

The project is not only about water or power, it carries a strategic undertone. By controlling a transboundary river, China gains leverage in its broader geopolitical contest with India. Water could potentially become a tool of coercion in future disputes. It raises deeper strategic and security concerns that go beyond the environment, touching upon sovereignty, national security, and the fragile balance of power in the Himalayan region. It will lead water as a geopolitical tool, vulnerability of the Northeast region, strategic concerns along the border, risks during armed conflict, lack of binding agreements etc.

4. Impact on local people and community

The Brahmaputra River is the lifeblood of India’s North-eastern region. Flowing through Arunachal Pradesh and Assam, it sustains agriculture, fisheries, forests, and the livelihoods of millions. China’s proposed super dam on the river’s upper reaches has sparked significant concern among these communities, as it could fundamentally alter their way of life. For India, understanding the human dimension is as critical as addressing ecological or strategic concerns. It will threat to agriculture and livelihoods, disruption of fisheries and aquatic resources, impact on culture and traditions, health and sanitation challenges, social and economic inequalities etc.

India’s Response

1. Diplomatic engagements

New Delhi has raised the issue with Beijing through bilateral mechanisms. While China reassures that its projects are “run-of-the-river” and will not harm downstream states, these assurances lack independent verification. New Delhi is exploring every diplomatic channel to protect its interests. India’s approach has been cautious yet consistent, combining bilateral dialogue, regional cooperation, and international advocacy. For enhancing this India is working on bilateral talks with China, pursuing greater data cooperation with China, engaging Bangladesh as a downstream partner, building a narrative of shared resources, linking water issues to border issues to broader ties, quiet but persistent diplomacy on Brahmaputra super dam.

2. Strengthening monitoring machine

India has enhanced its monitoring systems on the Brahmaputra to track river flow and prepare for contingencies. Agreements for data sharing on river levels exist, but they remain limited in scope. India’s response, another crucial element has been the strengthening of its monitoring machinery is a system designed to track river flows, anticipate risks, and protect vulnerable communities. India’s is working on expanding hydrological infrastructure, satellite and remote sensing capabilities, early warning system for communities, data sharing and cross-border cooperation, military and strategic surveillance, research and technological innovation etc.

3. Domestic dam projects

India cannot directly control China’s upstream actions, it has begun working on domestic dam projects within its territory to balance the risks. These projects serve multiple purposes: safeguarding water availability, strengthening energy capacity, and enhancing India’s negotiating position. India is working on “The Subansiri Lower Hydroelectric Project” on Sibansiri river (2,000 MW), “The Siang Basin Projects” on Siang Basin, Dibang Multipurpose Project in Arunanchal Pradesh (3,000 MW) etc. India’s domestic dam projects on the Brahmaputra and its tributaries represent a proactive response to China’s super dam initiative. Through projects like Subansiri Lower, Dibang Multipurpose, and Siang Basin hydropower stations, India is creating a counterbalance that combines energy security with strategic preparedness.

4. International outreach

India emphasizes the principle of equitable and reasonable use of transboundary rivers, drawing global attention to the risks of unilateral projects. However, since China is not party to international water treaties like the UN Watercourses Convention, diplomatic options remain limited. Recognizing that unilateral action by China could alter river flows and destabilize entire ecosystems, New Delhi has widened its international outreach to safeguard national and regional interests. Including this, India is also working on building partnerships with downstream Bangladesh, raising awareness in multilateral forums, engaging with regional partners in south and Southeast Asia, collaboration with international research institutions, linking water security with climate diplomacy, soft power and moral positioning etc.

5. Strategic preparedness

China’s ambitious plan to construct a super dam on the Brahmaputra River in Tibet has unsettled policymakers in New Delhi. The project, touted as one of the largest hydropower ventures in the world, is more than just an energy initiative. For India, it raises deep concerns about water security, ecological balance, and strategic vulnerability. In response, India has been quietly shaping a multi-layered strategy to safeguard its interests and prepare for the challenges that lie ahead. Through this India is focusing on strengthening domestic hydropower projects, expanding hydrological surveillance, military readiness in the Northeast, diplomatic and legal measures, regional cooperation with Bangladesh, emphasis on community preparedness etc.

6. People-centric measures

The construction of a massive hydropower dam by China on the upper reaches of the Brahmaputra River has raised concerns in India, not only at the policy level but also among the millions of people who depend on the river. While diplomatic and strategic steps are critical, India has increasingly focused on people-centric measures that directly address the needs and anxieties of communities living along the Brahmaputra basin. India is focusing on ensuring reliable water data for communities, strengthening flood preparedness and relief systems, promoting alternative livelihoods, building local water storage and irrigation projects, strengthening research and public awareness, regional and cross-border cooperation for people’s benefit etc.

7. Way Forward

China’s super dam is a reminder that water security is becoming as crucial as energy or defence security in the 21st century. For India, the challenge lies in balancing ecological preservation with strategic imperatives. Greater investment in dialogue, regional cooperation, and alternative energy within its own territory may help reduce vulnerabilities. At the same time, building awareness about the Brahmaputra’s significance as a shared heritage of Asia could pressure China toward more transparent and cooperative approaches. Ultimately, the Brahmaputra is not merely a river, it is a lifeline for millions across South Asia. Treating it as a strategic bargaining chip risks not only diplomatic tensions but also human survival and ecological stability. India’s cautious yet firm response must therefore aim at safeguarding both national interests and the rights of communities who live by the river’s flow.

Conclusion

China’s proposed construction of a super dam on the Brahmaputra River represents more than an engineering project; it encapsulates ecological, strategic, and diplomatic challenges with direct consequences for India. The ecological concerns stem from the possibility of altered river flow, depletion of aquatic biodiversity, and disruption of fragile Himalayan ecosystems. For India, which depends heavily on the Brahmaputra for agriculture, fisheries, and the sustenance of millions in the Northeast, these risks translate into livelihood insecurity and potential displacement of local communities. Beyond environmental anxieties, the project also carries significant strategic implications. As the upper riparian state, China gains a decisive advantage by exercising control over the flow of transboundary waters, creating asymmetry in water security. This dynamic amplifies India’s vulnerability not only in terms of resource dependence but also within the broader context of regional geopolitics, where water could emerge as a tool of leverage.

India’s responses so far have combined diplomatic engagement, technical assessment, and regional cooperation initiatives. However, the absence of a binding water-sharing treaty with China limits the scope of legal or institutional redress. Consequently, India’s policy options lie in strengthening bilateral dialogues, investing in robust hydrological data systems, and engaging in multilateral platforms to highlight the necessity of sustainable and equitable transboundary water governance.

In sum, the super dam project underlines the urgency for India to balance immediate concerns with long-term strategies. While it cannot prevent China’s unilateral actions, India can mitigate risks by fostering regional solidarity, enhancing domestic resilience, and promoting global norms for responsible river management. The Brahmaputra’s future, therefore, is not only a matter of bilateral contention but also a test of cooperative water diplomacy in Asia.