The Ganges Water Treaty of 1996 is a bilateral treaty between India and Bangladesh, signed on December 12, 1996, in New Delhi by Prime Ministers H. D. Deve Gowda and Sheikh Hasina Wajed. The treaty was created to resolve a long-standing dispute over the sharing of the Ganges River's water, which had been exacerbated by India's construction of the Farakka Barrage in 1975 to divert water to the Hooghly River for the navigability of Calcutta Port. The treaty replaced a period of no operational mechanism (1989-1996) and earlier interim arrangements.
The treaty is a 30-year framework for cooperation, set to expire in December 2026, and is subject to review every 5 years. It governs the sharing of water at Farakka during the lean season, from January 1 to May 31, based on 10-day periods. The sharing mechanism is a three-tiered formula based on the flow at Farakka, which was derived from 40 years of average flow data (1949–1988). For instance, if the flow is less than 70,000 cusecs, the water is shared 50:50. A key provision is the guarantee that India and Bangladesh each receive 35,000 cusecs in alternate three 10-day periods between March 11 and May 10. Furthermore, Article II(iii) includes an emergency clause for immediate consultations if the flow falls below 50,000 cusecs. A Joint Committee monitors the daily flows at Farakka and at the Hardinge Bridge in Bangladesh.
The treaty is the sole water-sharing agreement for the 54 transboundary rivers shared by the two nations, and its renewal is currently a major topic of discussion. While the treaty has not been amended, both countries have begun technical-level talks for its renewal, with a new agreement needing to address the impact of climate change, which was not factored into the original 1949–1988 data.