Bihar seeks resolution as India’s Ganga water sharing treaty with Bangladesh expires this year

The Ganga water-sharing treaty is a 1996 agreement between upstream India and downstream Bangladesh. It governs how the river’s water is divided from January through June, when flows are low. The treaty is due to end this year. Its renewal matters because both countries rely on predictable water deliveries, while Bihar says its own needs are not adequately protected.

The agreement uses water measured at the Farakka barrage. If flows are below 70,000 cusecs, India and Bangladesh receive equal shares. At 70,000–75,000 cusecs, Bangladesh gets 35,000 cusecs and India receives the remainder. At 75,000 cusecs or more, India gets 40,000 cusecs and Bangladesh receives the rest.

Bihar wants the renewal to include stronger arrangements for its agriculture, drinking water, industry and long-term security. Its leaders seek water from upstream basin states during dry months. Bangladesh’s guaranteed flows and Bihar’s demands therefore make renewal a regional water-management issue, not only a bilateral agreement.

During the January-to-June lean season, the treaty divides Ganga water according to the flow recorded at Farakka barrage. This matters because river levels are lowest then, making every allocation more significant for drinking water, farming and other uses.

When the flow is below 70,000 cusecs, India and Bangladesh each receive half. If the flow is between 70,000 and 75,000 cusecs, Bangladesh is assured 35,000 cusecs, while India gets the balance. When flow reaches 75,000 cusecs or more, India receives an assured 40,000 cusecs and Bangladesh gets the remainder.

The treaty adds special Bangladesh guarantees. Bangladesh receives 35,000 cusecs during the first and last ten days of April, and 27,633 cusecs from April 11 to 20. If flow falls below 50,000 cusecs in any ten-day period, India and Bangladesh must consult immediately about emergency adjustments.

The treaty manages very large flows measured in cubic feet per second, or cusecs. Bangladesh is assured 35,000 cusecs during specified parts of April. India is assured 40,000 cusecs when Farakka’s flow reaches at least 75,000 cusecs. These figures define the agreement’s central sharing mechanism.

The treaty also specifies 27,633 cusecs for Bangladesh from April 11 to 20. When flow is below 70,000 cusecs, the countries divide it equally. If any ten-day period drops below 50,000 cusecs, they must consult on emergency changes. These thresholds apply at Farakka during the January-to-June lean season.

Bihar’s request is much smaller in absolute volume but important locally. The state government has sought 2,000 cusecs for drinking and industrial use during the lean period. An internal committee reportedly recommended 900 cusecs instead. The figures illustrate the different scales of the bilateral treaty and Bihar’s state-level demand.

Bihar argues that the treaty does not adequately reflect its position in the Ganga basin. The state says it has only about 16% of the river’s total catchment area, yet it must provide half of Farakka’s required water during the lean season. Bihar says much of that contribution comes through tributaries flowing across the state.

Its leaders connect the issue directly to daily needs. Sanjay Jha said adequate Ganga water is essential for agriculture, drinking water, industrial development and long-term security. Bihar’s government has demanded 2,000 cusecs for drinking and industry during the lean period. It also wants upstream states to release a proportionate and sizable amount of water into the river.

Bihar’s concern is disputed. Himanshu Thakkar said the claim that the treaty pressures Bihar over minimum flow is made solely by the state government, with no supporting evidence. Renewal could therefore become a debate over both water allocation and the evidence used to assess Bihar’s needs.

The Farakka barrage is the point where the treaty measures Ganga flow and applies its sharing rules. The article does not provide a fuller engineering description of the barrage. Its importance here is practical: readings there determine how much water India and Bangladesh receive during the January-to-June lean period.

Bihar says the water reaching Farakka partly comes through tributaries flowing across the state. In 2017, Bihar’s then water resource minister said the Ganga carried only 14,126 cusecs when it entered Bihar near Buxar, while Bihar was expected to help deliver at least 52,972 cusecs through the Ganga at Farakka under the treaty. Another state document reported only 400 cusecs at Chausa during February–April.

Bihar therefore wants Ganga basin states to share responsibility for supplying water. Nitish Kumar called for an urgent mechanism to release a proportionate or sizable amount from upper-basin states during lean seasons. The dispute concerns how flows are built up before reaching Farakka.

If the treaty is renewed without addressing Bihar’s concerns, the state says its dry-season water security could weaken. Bihar links reliable Ganga flows to agriculture, drinking water, industrial development and its broader future needs. The concern is especially sharp when river levels fall between January and June.

The state says it contributes to the flow needed at Farakka even though only about 16% of the Ganga’s total catchment lies in Bihar. Reported figures vary sharply by location: the flow at Chausa was described as 400 cusecs during February–April, while Kahalgaon averaged about 1,600 cusecs. Bihar has sought 2,000 cusecs for drinking and industry, but an internal committee reportedly recommended 900.

The consequences remain contested. Himanshu Thakkar said there is no evidence that the treaty is creating pressure on Bihar’s minimum flow. Still, Bihar wants renewal to include assured allocations and releases from upper-basin states, making future negotiations more regional.

A river basin collects water from the main river and its tributaries. Upstream states can reduce downstream flow by withdrawing water for farms, cities or industry. Tributaries can add water before it reaches Bihar or Bangladesh. These processes help explain why a treaty measured at Farakka is connected to conditions across the wider Ganga basin.

The article gives two concrete examples. Bihar says around a dozen rivers join the Ganga within the state. It also reports 400 cusecs at Chausa during February–April but about 1,600 cusecs at Kahalgaon. This difference shows that flows can change as water enters or moves through the basin. Dams can store or release water, while sediment can alter channels and storage; these mechanisms are established river-science principles, not details provided by the article.

Bihar wants basin states to share responsibility for meeting India’s Bangladesh obligation. A future arrangement would need to consider regional water use and lean-season needs, while the treaty’s existing thresholds would still govern sharing at Farakka.