As Union Home Minister Amit Shah steps into efforts to resolve the decade-long Mahanadi water dispute between Odisha and Chhattisgarh, attention is once again on the sharing and use of the river's waters. After years of stalled tribunal proceedings, the dispute shifted towards political negotiations in 2025–26.
Earlier, the Centre extended the tenure of the Mahanadi Water Disputes Tribunal by nine months, from April 14, 2026, to January 13, 2027, giving the two states more time to reach a settlement.
The roots of the dispute go back to the development of the Mahanadi basin and the construction of the Hirakud Dam.
In 1945, a high-level conference in Cuttack examined ways to manage the Mahanadi basin, particularly its recurring floods. In 1947, central water authorities (the predecessor of today's Central Water Commission) proposed three dams on the river, with flood control as the primary objective and irrigation and hydropower as additional benefits.
Only one was eventually built: the Hirakud Dam near Sambalpur. Construction began in 1948, and the multipurpose project was dedicated to the nation by Prime Minister Jawaharlal Nehru in 1957. At 25.8 km, Hirakud became India's longest earthen dam.
For decades, the upstream-downstream relationship did not develop into a major interstate conflict. Chhattisgarh was part of Madhya Pradesh and had relatively limited water infrastructure, while Odisha had developed Hirakud as a major multipurpose project.
That changed after Chhattisgarh became a separate state on November 1, 2000.
The new state expanded irrigation and industrial activity and began developing infrastructure to use the Mahanadi's waters.
A key feature of the project later became central to the dispute: much of Hirakud's upstream catchment lies in what is now Chhattisgarh. Official material cited in the dispute puts Chhattisgarh's share of the catchment up to Hirakud at 89.9%.
As upstream development increased, so did Odisha's concerns about the volume of water reaching the state.
The immediate flashpoint was the construction of a series of barrages and other water structures by Chhattisgarh upstream of Hirakud.
The dispute particularly focused on six industrial barrages constructed between 2011 and 2017. Odisha argued that these structures could reduce downstream flows, especially during the non-monsoon months, affecting irrigation, fisheries, drinking-water supplies and the Hirakud system.
Chhattisgarh maintained that the six barrages had a combined storage capacity of about 0.22 million acre-feet and argued that the projects were within the state's right to develop its water resources.
The disagreement eventually moved into the courts. Odisha approached the Supreme Court in 2016 over Chhattisgarh's upstream projects. The Mahanadi Water Disputes Tribunal was subsequently constituted in March 2018 under the Inter-State River Water Disputes Act, 1956.
Odisha's position
Odisha, as the downstream state, says upstream structures have reduced flows into the state, particularly during the lean season. It argues that inadequate flows could affect agriculture, fisheries, drinking-water supplies and the inflows needed by the Hirakud reservoir.
Chhattisgarh's position
Chhattisgarh argues that it has a right to develop and use the Mahanadi's waters within its territory. It points to its share of the basin: 52.9% of the total Mahanadi catchment and 89.9% of the catchment up to Hirakud as part of its case for using the river's waters for irrigation, industry and other development needs.
At its core, the dispute is over how the Mahanadi's waters should be shared between an upstream state seeking to develop its water resources and a downstream state dependent on adequate flows.