Published: 11:43 PM, 21 September 2026
The High-Stakes Geopolitics of Upper Siang Hydroelectric Project and Its Impacts on Bangladesh
At the crossroads of geopolitics, climate volatility and human survival lies the mighty river system that originates as the Yarlung Tsangpo in Tibet, carves through Arunachal Pradesh as the Siang, and swells into the Brahmaputra in India and the Jamuna in Bangladesh.
This single, interconnected hydrological system sustains the lives and livelihoods of an estimated 130 million people. Yet, this fragile basin is increasingly becoming a theater of hydro-strategic competition.
At the epicenter of this tension sits the proposed Upper Siang Hydroelectric Project (SUMP)—a massive infrastructural intervention conceived by New Delhi to counter upstream maneuvers by Beijing, but one that introduces profound risks of ecological disruption, social displacement, and geopolitical friction for local communities and downstream nations alike.
As the region edges toward an unpredictable hydrological future—compounded by the impending expiration of the 1996 Ganges Water Sharing Treaty in December 2026—the SUMP epitomizes a dangerous paradox: a remedy for transboundary insecurity that threatens to trigger the very crises it seeks to avert.
The Geopolitical Impasse and the Dam for a Dam Race
To understand the threats posed by the SUMP, we must first understand the structural asymmetry that defines the Brahmaputra basin. Unlike the Indus basin, governed by the Indus Waters Treaty between India and Pakistan, India and China share no binding legal framework for the Brahmaputra.
Cooperation relies entirely on fragile, goodwill-based memorandums of understanding concerning data sharing.
This leaves India in a vulnerable lower-riparian position relative to China, a vulnerability brutally exposed in the past. In 2000, a natural debris dam in Tibet breached without warning, unleashing a catastrophic flash flood down the Siang River that killed over 30 people, destroyed bridges, wiped out villages, and rendered thousands homeless in Arunachal Pradesh.
Similarly, following the 73-day Doklam standoff in 2017, China abruptly suspended flood-season data sharing with India under the guise of technical upgrades—even as it continued seamless, real-time data transmissions to Bangladesh from the exact same river basin. Left without advance warning, Indian riverside communities faced severe, unmitigated flooding.
Faced with China’s aggressive upstream hydropower expansion—including massive dam sites near the Great Bend and Medog on the Yarlung Tsangpo—Indian policymakers have championed the SUMP. Union Minister Kiren Rijiju described the project as a “strategic necessity” for national security, while Arunachal Pradesh Chief Minister Pema Khandu emphasized its role in flood control and mitigating potential water surges from upstream Chinese operations.
Yet, this defensive posture has locked the region in high-stakes geopolitics. This situation can be described as a perilous “dam for a dam race between China and India.” Rather than fostering regional stability, this competitive escalation threatens to transform a natural river ecosystem into a heavily militarized hydrological battleground, with downstream populations caught in the crossfire.
Displacement, Ecological Damage and Indigenous Rights in Arunachal Pradesh and Assam
Within Arunachal Pradesh, the SUMP is a flashpoint of fierce contention. To its supporters, the project represents an essential shield against upstream water manipulation and a source of national hydropower. But to local residents and indigenous communities, it threatens an irreversible assault on their ancestral homelands, rights and livelihoods.
The project raises deep-seated concerns regarding:
Mass Displacement: Large-scale inundation threatens to uproot indigenous populations who have lived in harmony with the Siang valley for generations, stripping them of their traditional lands and cultural heritage.
Erosion of Indigenous Rights: Local communities fear that strategic national security imperatives will override their constitutional and customary land rights, marginalizing them in decision-making processes.
Ecological Degradation: The alteration of natural river flows threatens aquatic biodiversity, fish migration routes and the rich riparian ecology of the Siang valley.
Further downstream in Assam, where the Brahmaputra supports approximately 83 million people (representing 34% of the basin's population in India), the stakes are equally high. The river acts as a primary economic driver across vital floodplain districts like Dhubri, Goalpara, Barpeta, Nalbari, Darrang, and the iconic 352-square-kilometer river island of Majuli.
While seasonal monsoons traditionally cause short-term infrastructure challenges, they also deposit vital, nutrient-rich alluvial silt across millions of hectares of farmland. This natural process replenishes groundwater and sustains rice crops that account for a staggering 96% of Assam’s total food grain production, occupying nearly 70% of its gross cropped area.
Intervening aggressively in the upper reaches through massive dam construction like the SUMP risks disrupting these delicate silt dynamics, threatening agricultural productivity and aggravating erosion across Assam's vulnerable riverbanks.
The Transboundary Fallout: Bangladesh as the Ultimate Terminal Sufferer
While the geopolitical sparring occurs between Beijing and New Delhi, the most severe consequences may be borne further downstream. Bangladesh, serving as the terminal riparian state of the Brahmaputra-Jamuna basin, is profoundly sensitive to any upstream alteration of seasonal flow patterns or sediment movement.
Although only about 8 percent of the Brahmaputra basin lies within Bangladesh, the river system contributes over 65 percent of the country’s total water supply, earning its designation as the “lifeline of Bangladesh.” About 91 percent of Bangladesh’s rivers originate outside its borders, and the Brahmaputra (Jamuna) alone accounts for roughly 70 percent of the nation’s yearly freshwater flow.
The impacts on Bangladesh’s socio-economic fabric are staggering:
Food Security and Agriculture: The river sustains the lives and food security of more than 34 million people, particularly in northern districts such as Kurigram, Gaibandha, Rangpur, Jamalpur, Sirajganj and Bogura. Agriculture employs nearly half of the rural population (48%) and contributes approximately 16% to the national GDP.
The Boro and Aman Rice Economies: The region produces the critical dry-season Boro rice crop—covering about 4.8 million hectares and yielding over 21 million metric tonnes, which amounts to 55% of national rice production. It also supports monsoon Aman rice, vital river fisheries and large-scale jute cultivation.
Marginal Thresholds of Survival: Hydrological experts warn that even a minor 10% drop in dry-season water availability can jeopardize national food security, while extreme monsoon fluctuations can submerge up to 30% of the delta. Because Bangladesh possesses a highly constrained capacity to adapt to sudden hydrological shifts, any upstream unilateral actions—whether stemming from China’s Medog complex or India’s SUMP—will introduce dangerous unpredictability into a system already battered by extreme monsoon variations.
Can a Single Dam Tame a Monsoon Basin?
Proponents of the SUMP argue that the dam will function as a “hydraulic cushion,” offering a risk-management tool to regulate seasonal flows, improve flood forecasting and stabilize dry-season water availability.
However, independent hydrologists and policy experts issue a strong caveat: in a monsoon-dominated system as vast and volatile as the Brahmaputra, no single dam can meaningfully control basin-wide hydrology.
The sheer volume of water generated during peak monsoon seasons dwarfs the storage capacity of any plausible engineering project. Rather than achieving absolute flood control or flow manipulation, the more realistic—and sobering—outcome of the SUMP is localized ecological stress, heightened geopolitical tension and false security.
True resilience cannot be engineered through competitive dam-building; it requires robust multilateral coordination, transparent data exchange, and binding legal frameworks that include all riparian states—China, India and Bangladesh alike.
A Converging Crisis: The Impending Expiry of the 1996 Ganges Treaty
The threat posed by the SUMP does not exist in a geopolitical vacuum. It converges dangerously with other looming water security deadlines in the region. Most notably, the 1996 Ganges Water Sharing Treaty—signed for a strict 30-year term to govern dry-season flows at the Farakka Barrage—is set to expire in December 2026.
The successful renewal of this treaty is non-negotiable. Should its renewal fail, the resulting legal and regulatory vacuum could trigger:
· A catastrophic regional water security crisis.
· Accelerated and severe salinity intrusion threatening coastal ecosystems and freshwater aquifers.
· Direct disruption to the livelihoods of over 60 million people across southwestern Bangladesh.
When superimposed upon the uncertainties introduced by upstream projects like the SUMP and China's Medog complex, the expiration of the Ganges Treaty highlights a terrifying trajectory: South Asia is sleepwalking into an era of compounded water scarcity, where uncoordinated engineering projects and institutional decay threaten the survival of over a hundred million vulnerable people.
The Upper Siang Hydroelectric Project captures the tragic dilemma of modern transboundary water governance. Conceived as a strategic shield to project national power and mitigate upstream vulnerabilities, it risks generating severe downstream turbulence, exacerbating ecological degradation, displacing indigenous communities, and alienating vital downstream neighbors like Bangladesh.
As India, China and Bangladesh navigate this high-stakes hydro-politics, the lesson of the Siang River is clear: water cannot be weaponized or hoarded without consequence. In a shared basin where 130 million lives hang in the balance, the pursuit of security through structural dominance is a zero-sum game.
True long-term survival demands moving away from the reckless momentum of a “dam for a dam” race, and instead forging cooperative, transparent and inclusive basin-wide management before the cascading crises of the Himalayas overwhelm the region entirely.
Emran Emon is an eminent
journalist, columnist and a
geopolitical analyst. He can be reached
