Policy Update
Ninchen Tamang
Background
The Ganga water dispute between India and Bangladesh is rooted in the river’s transboundary character and the competing dry-season water needs of both countries. The dispute intensified after India commissioned the Farakka Barrage in May 1975 to divert Ganga water into the Bhagirathi-Hooghly system, primarily to improve the navigability and functioning of Kolkata Port (Ministry of Jal Shakti, 2023). The diversion of lean-season flows became a major concern in Bangladesh, where downstream water availability has implications for irrigation, navigation, ecosystems, and water-dependent livelihoods.
The first major bilateral arrangement was the 1977 Ganges Water Agreement, which established dry-season sharing through 10-day periods. Subsequent MoUs in 1982 and 1985 provided temporary arrangements, but after the latter expired in 1988, no comprehensive sharing framework remained until the 1996 Ganges Water Treaty.
The Ganges Water Sharing Treaty was signed on 12 December 1996 for a period of 30 years and entered into force immediately. It governs the sharing of lean-season Ganga flows at Farakka from 1 January to 31 May through 10-day assessments. Unlike the 1977 agreement, the 1996 Treaty does not contain a general 80% minimum-guarantee clause. However, Article XI provides that, if the two countries fail to reach agreement following a review under Article X, India will release water at a rate not less than 90% of Bangladesh’s share until a mutually agreed flow arrangement is reached (Government of the Republic of India[GoI] & Government of the People’s Republic of Bangladesh[GoB],1996).
Institutionally, the Treaty established a Joint Committee comprising representatives from both countries to oversee implementation, including discharge measurements at Farakka in India and Hardinge Bridge in Bangladesh, and to facilitate the exchange and examination of hydrological data. This mechanism has provided a continuing technical framework for bilateral water-sharing cooperation (GoI & GoB,1996).
The Treaty is due to expire in December 2026. Its renewal comes amid concerns over changing hydrological conditions, rising domestic and agricultural demand, climate variability, and ecological sustainability. As of 13 February 2026, the Government of India stated in Parliament that discussions on renewal had not yet commenced between the two countries (Ministry of External Affairs, 2026). The renewal process therefore presents an opportunity to preserve the Treaty’s cooperative mechanisms while reassessing whether its existing allocation framework remains appropriate under changing hydrological conditions.
Source– Adapted by the author from Rahman et al. (2019), with modifications https://doi.org/10.2166/wp.2019.164
Functioning
The Ganges Water Treaty establishes a seasonal, measurement-based system for sharing river flows at Farakka, applying annually during the dry season from 1 January to 31 May, divided into successive 10-day periods, with allocations determined under the formula in Annexure I based on flow recorded at Farakka (GoI & GoB, 1996).
Under this formula, if availability at Farakka is 70,000 cusecs or less, flow is shared equally. Between 70,000 and 75,000 cusecs, Bangladesh receives 35,000 cusecs and India the balance; above 75,000 cusecs, India receives 40,000 cusecs and Bangladesh the balance (GoI & GoB, 1996).
A more stringent condition applies to the critical period from 11 March to 10 May, where Annexure I guarantees each country 35,000 cusecs in alternate three ten day periods. (GoI & GoB, 1996). If flow at Farakka falls below 50,000 cusecs in any 10-day period, the two governments must enter immediate consultations to make adjustments “on an emergency basis,” guided by equity, fair play, and no harm to either party (GoI & GoB, 1996, Article II).
Implementation is overseen by a Joint Committee with equal representation from both countries, which monitors flows at the Farakka feeder canal and Hardinge Bridge, exchanges hydrological data, examines implementation difficulties, and submits reports to both governments (GoI & GoB, 1996, Articles IV-VII). Unresolved disputes escalate to the Indo-Bangladesh Joint Rivers Commission and, if needed, to the two governments directly (Article VII). Article III further limits India’s withdrawals for “reasonable use” between Farakka and the Bangladesh border to no more than 200 cusecs (GoI & GoB, 1996, Article III).
Formally, the treaty is a binding allocation mechanism with defined thresholds and dispute pathways. Yet it functions as more than an allocation formula: through the Joint Committee, it creates a recurring institutional process for measuring flows and resolving disputes. Although the treaty expires in 2026 (Article XII), leaving renewal uncertain, this institutional continuity remains its most consistent contribution to India-Bangladesh water relations
Source: Adapted by the author from the Ganges Water Sharing Treaty (1996), Annexure I.
Performance
The 1996 Ganges Water Sharing Treaty has performed relatively well as a mechanism for conflict management and bilateral cooperation. It replaced temporary arrangements with a 30-year framework for sharing lean-season flows at Farakka and established procedures for joint monitoring, data exchange, and consultation. The Joint Committee has provided a continuing institutional channel for managing a politically sensitive issue and has helped sustain bilateral engagement over the Ganges (Ministry of Jal Shakti, 2023).
Its performance in ensuring predictable downstream water availability, however, has been more mixed. The allocation formula rests on the 1949–1988 historical average flow at Farakka (GoI & GoB, 1996, Annexure II) and does not fully account for later changes in dry-season discharge, upstream abstraction, and hydrological variability.
The formula is calculated at Farakka, while Hardinge Bridge serves as the downstream monitoring point in Bangladesh (GoI & GoB, 1996, Article IV).Comparing the two helps assess whether releases are reflected downstream, though a shortfall at Hardinge Bridge cannot automatically be read as non-compliance: tributary inflows, intervening withdrawals, river morphology, and measurement limitations can all contribute.
A quantitative assessment of 1997–2016 data by Rahman et al. (2019) found Bangladesh received less water at Hardinge Bridge than presumably released from Farakka in 31% of 300 recorded periods. During the six critical periods between 11 March and 10 May, the failure rate rose to 43% (52 of 120), reaching 65% (39 of 60) during the three guaranteed periods when Bangladesh held the guaranteed 991 m³/s floor.
Thomas (2017) offers a more direct measure, using releases at Farakka itself rather than downstream arrivals. Between 1997 and 2016, India generally adhered to the treaty, releasing, on average, more water than the indicative schedule required, with shortfalls occurring in only around 20% of cases between 2008 and 2016. However, compliance was weaker during critical low-flow periods: India did not provide Bangladesh with the stipulated minimum quantity in 15 of 27 instances, or 55.5%, between 2008 and 2016 (Thomas, 2017). These findings suggest that the treaty’s main weakness is not overall non-compliance, but timing shortfalls concentrated precisely in the periods when water is most needed.
Overall, the treaty has performed more successfully institutionally than hydrologically, sustaining cooperation while struggling to guarantee reliable flows during the driest, most consequential weeks.
Impact
The 1996 Ganga Water Sharing Treaty has had a dual impact: it stabilised India-Bangladesh relations and created a predictable framework for dry-season water sharing, but it has not fully resolved Bangladesh’s downstream water-security concerns. Its most significant achievement has been diplomatic. By institutionalising a defined allocation formula, joint monitoring and regular consultation, the treaty transformed a long-standing dispute into a recurring process of measurement and negotiation, reducing the scope for unilateral action and providing a stable basis for wider bilateral cooperation.
The treaty has also produced sectoral benefits by improving the predictability of dry-season sharing and supporting planning for irrigation, navigation and other downstream uses. For India, it has facilitated the continued operation of the Farakka Barrage and supported water management linked to the Kolkata waterway. However, its benefits have been less consistent during drought years and periods of exceptionally low discharge, when the limitations identified in its performance become most evident and downstream communities remain vulnerable to water scarcity, salinity intrusion and declining navigability.
Its environmental impact has been more limited. The treaty is primarily concerned with volumetric allocation and does not establish a comprehensive framework for fisheries, salinity management, water quality, sediment transport, ecological flows or basin-wide river management. Consequently, wider concerns over river health and climate-related changes remain largely outside its core framework, while an allocation system designed around historical flow patterns faces increasing pressure from changing hydrological conditions.
Thus, while the treaty successfully converted a highly contentious dispute into an institutionalised framework for cooperation, its impact on actual downstream water security has remained uneven. Its principal strengths lie in conflict management and bilateral stability, whereas its principal limitations arise from the gap between a historically derived allocation formula and the increasingly uncertain hydrological, ecological and developmental conditions of the Ganga basin. Renewal should therefore preserve the Joint Committee and the treaty’s principles of equity, fairness and no harm while introducing adaptive allocation, transparent data exchange, downstream verification and greater consideration of river health.
Emerging Issues
As the 1996 Ganga Water Treaty approaches its December 2026 expiry, several challenges have become more pronounced. These challenges are hydrological, environmental, political and institutional, making a simple extension of the existing framework increasingly difficult.
Climate change and growing hydrological variability are among the most significant concerns. The treaty was not designed around contemporary climate projections and lacks a sufficiently adaptive mechanism for responding to changing river conditions. Its allocation framework is based on historical flow patterns from 1949–1988 and may not adequately reflect evolving patterns of precipitation, glacier melt, evaporation and dry-season discharge. Increasing variability between low- and high-flow periods has further reduced the reliability of a fixed allocation approach, particularly during critical dry-season months. This also strengthens the case for incorporating adaptive ecological thresholds, rather than relying on a single fixed environmental-flow requirement, so that ecological needs can be assessed and protected under different hydrological conditions.
Ecological degradation and river health have become increasingly relevant to the future of the Ganga Water Sharing Treaty. The 1996 treaty primarily focuses on allocating dry-season flows at Farakka and contains limited provisions concerning environmental flows, water quality, or broader ecological management. Research comparing pre- and post-Farakka flow conditions found significant alterations in dry-season and minimum flows in the Lower Ganges Basin. Such hydrological changes have been associated with increased salinity intrusion and disruptions to fisheries, agriculture and other downstream ecosystems in Bangladesh (Gain & Giupponi, 2014). These concerns underline the need for any renewed framework to move beyond water allocation alone and incorporate environmental flows and ecological sustainability as part of long-term Ganga basin governance.
Finally, institutional and data-sharing gaps remain. Although the treaty provides for monitoring and information exchange, it lacks a comprehensive real-time data-sharing mechanism and a flexible system for prolonged drought conditions. Concerns over downstream availability at Hardinge Bridge also highlight the limitations of focusing primarily on flows at Farakka. These gaps can make coordinated responses more difficult when river discharge falls sharply.
Way Forward
Renewal of the 1996 Ganga Water Sharing Treaty should preserve its central principles of negotiated sharing, equity, fairness and mutual accommodation while updating the framework for contemporary hydrological and ecological conditions. Since the treaty is due to complete its initial 30-year term in December 2026, the renewal process should produce more than a simple extension of the existing allocation schedule (GoI & GoB, 1996).
First, institutional reforms should strengthen the governance of water sharing during normal and low-flow conditions. The renewed treaty should establish a clearly defined drought-sharing protocol, specifying the flow thresholds that trigger consultations, the information to be exchanged, time limits for governmental responses and the manner in which scarcity will be shared during prolonged low-flow periods. Advance notification and consultation should also be required for major infrastructure or diversion projects likely to affect lean-season flows. These measures would make the principles of equity and mutual accommodation more operational.
Second, technical reforms should improve the accuracy and responsiveness of treaty implementation. The parties should adopt a dynamic, climate-responsive allocation mechanism by supplementing the historical 1949–1988 flow baseline with recent hydrological observations, updated basin modelling and climate-risk assessments. A revised reference period should be reviewed at fixed intervals so that allocations reflect changing dry-season discharge rather than relying exclusively on historical averages (Rahman et al., 2019).
India and Bangladesh should also create a jointly managed real-time hydrological data portal publishing verified observations from Farakka and Hardinge Bridge, alongside relevant rainfall, water-level and discharge data. Joint calibration of instruments and agreed procedures for resolving discrepancies would improve confidence. Compliance should further be assessed at both the release and downstream observation points, accounting for intervening withdrawals, tributary inflows, river morphology and measurement uncertainty.
Third, ecological reforms should integrate environmental sustainability into routine treaty implementation. Ecological safeguards should include indicators relating to salinity, fisheries, sediment, water quality and minimum environmental-flow requirements. Joint monitoring and periodic review of these indicators alongside the allocation formula would ensure that ecological concerns are addressed systematically rather than as an afterthought.
Finally, regional cooperation should broaden the treaty beyond water allocation alone. Linking the renewed framework with cooperation on flood forecasting, navigation, pollution control and restoration of the wider Ganga–Padma system would strengthen long-term basin governance and support a more integrated approach to shared river management.
References
Government of the People’s Republic of Bangladesh, & Government of the Republic of India. (1996). Treaty between the Government of the People’s Republic of Bangladesh and the Government of the Republic of India on sharing of the Ganga/Ganges waters at Farakka. Asian Development Bank. https://lpr.adb.org/sites/default/files/resource/1610/ganges-water-sharing-treaty-1996.pdf
Ministry of External Affairs, Government of India. (2026, February 13). Ganga water sharing treaty (Lok Sabha Unstarred Question No. 2405). https://www.mea.gov.in/lok-sabha?dtl/40759/QUESTION_NO_2405_GANGA_WATER_SHARING_TREATY
Ministry of Jal Shakti, Department of Water Resources, River Development and Ganga Rejuvenation. (2023). Annual report 2022–23. Government of India. https://www.jalshakti-dowr.gov.in/static/uploads/2024/05/2023041116.pdf
Rahman, K. S., Islam, Z., Navera, U. K., & Ludwig, F. (2019). A critical review of the Ganges Water Sharing arrangement. Water Policy, 21(2), 259–276. https://doi.org/10.2166/wp.2019.164
Thomas, K. A. (2017). The Ganges water treaty: 20 years of cooperation, on India’s terms. Water Policy, 19(4), 724–740. https://doi.org/10.2166/wp.2017.109
Gain, A. K., & Giupponi, C. (2014). Impact of the Farakka Dam on thresholds of the hydrologic flow regime in the Lower Ganges River Basin (Bangladesh). Water, 6(8), 2501–2518. https://doi.org/10.3390/w6082501
Mishra, A. (2026, July 31). Treaty at the crossroads: Climate pressures and the future of Ganges Basin water governance. South Asian Voices. https://southasianvoices.org/geo-m-in-n-ganges-basin-governance-07-31-2026/
Mital, A. R. (2016). Indo-Bangladesh water sharing issues. International Journal of Humanities and Social Science Research, 2(11), 7–11. https://www.socialsciencejournal.in/assets/archives/2016/vol2issue11/2-10-29-735.pdf
About the Contributor
Ninchen Tamang is a Research & Editorial intern at Impact and Policy Research Institute (IMPRI). She holds a Master’s degree in Political Science, with primary research interests spanning geopolitics, international relations, foreign policy, and South Asian studies.
Acknowledgement
The author extends sincere gratitude to the Impact and Policy Research Institute (IMPRI) team for their expert guidance and constructive feedback throughout the process. I also extend my sincere thanks to Divya Nataranjan and Anushree Khare for their constructive reviews and editorial support.
Disclaimer
All views expressed in the article belong solely to the author and not necessarily to the organization.
