Efforts are on to find a settlement to the decade-old dispute between Odisha and Chhattisgarh over sharing of Mahanadi River waters.
The process, being facilitated by the Ministry of Jal Shakti and the Central Water Commission (CWC), has moved into technical discussions and mediation, even as the Mahanadi Water Disputes Tribunal (MWDT) continues with the adjudication. Its deadline has been extended to January 2027.
The dispute has its roots in water development in the Mahanadi basin going back several decades. It became an inter-state dispute after Chhattisgarh's formation and the construction of water infrastructure upstream. An agreement reached between Odisha and Madhya Pradesh in 1983 was only for cooperation in construction of inter-state projects; it did not address the sharing of water. The legal battle, the tribunal's examination of the issues, the competing claims of the two states and the latest efforts at a negotiated settlement have all shaped the case.
Here is what led to the dispute, how it developed and what remains to be resolved.
Why was the Mahanadi Water Disputes Tribunal constituted?
The immediate legal dispute followed Odisha's objections to water infrastructure constructed by Chhattisgarh upstream on the Mahanadi and its tributaries.
Odisha filed a statutory complaint with the then Ministry of Water Resources, under Section 3 of the Inter-State River Water Disputes (ISRWD) Act, 1956, in November 2016.
It also approached the Supreme Court in December 2016 through Original Suit No. 1/2017 under Article 131 of the Constitution.
The Union government constituted an 11-member Negotiation Committee in January 2017 to try to resolve the dispute. Odisha did not participate in its proceedings.
In January 2018, the Supreme Court directed the Central Government to constitute a water disputes tribunal for the Mahanadi basin. The Ministry of Water Resources notified the constitution of the Mahanadi Water Disputes Tribunal (MWDT) in March 2018 through a Gazette Notification and forwarded to it the November 2016 complaint by Odisha for adjudication.
In March 2019, Chhattisgarh filed its own complaint under Section 3 of the ISRWD Act with the MoWR. The Union Ministry forwarded this also to the Tribunal already constituted, for adjudication. This became known as Reference 2.
What is the older history behind the dispute?
The history of water development in the Mahanadi basin goes back to the 1940s.
In 1945, a high-level conference was convened in Cuttack to formulate comprehensive flood-control strategies and basin-wide water management plans.
In 1947, the Central Water Commission (CWC) proposed three dams across the Mahanadi river, all three in Odisha, to address primarily flood mitigation, with irrigation and hydroelectric power generation as secondary benefits.
Construction of Hirakud began near Sambalpur, Odisha, in 1948. The multipurpose project was completed and dedicated to the nation by Prime Minister Jawaharlal Nehru in 1957.
The earthen dam, at 25.8 km, became the longest earthen dam in India.
How did it become an inter-state dispute?
Out of the three dams proposed, the CWC constructed only one, the Hirakud, which is in Odisha, but very close to the Chhattisgarh-Odisha border. Thus, the dam is heavily dependent on inflow generated in the state of Chhattisgarh. For more than five decades, this skewed use of water resources accruing in Chhattisgarh but used by Odisha remained dormant because the upstream region had limited water infrastructure.
The situation changed after Chhattisgarh was carved out as the 26th State of the Indian Union on November 1, 2000.
The newly formed state accelerated irrigation development, industrialisation and began planning increased use of its water resources.
This brought the earlier upstream-downstream issues into sharper focus.
What was the immediate trigger?
The immediate flashpoint was the construction of six barrages across the main stem of the Mahanadi by Chhattisgarh between 2011 and 2017 for industrial, drinking and irrigation needs.
They were categorised under Culturable Command Area (CCA) criteria as minor projects, for industrial supply.
Odisha objected to the structures, saying upstream interception would affect non-monsoon flows into the Hirakud reservoir.
Chhattisgarh maintained that the combined storage capacity of the six barrages was 0.22 Million Acre-Feet (MAF) compared with the total river yield, and in any case the state has a right to use its water resources.
What did the Tribunal examine?
Odisha’s complaint to the MoWR focused on continuation of the use of water at Hirakud, as has been going on for decades. Chhattisgarh’s complaint sought an equitable apportionment of the water resources of the entire basin.
The tribunal framed 46 separate issues for adjudication.
The issues cover questions relating to water availability, existing and proposed utilisation, water-sharing as per principles of equitable apportionment, and other technical matters.
How many of those issues have been settled?
Fifteen of the 46 issues have been settled. These include water availability assessments, validation of baseline yield calculations, and parameters relating to alternative resources.
What issues remain pending?
Thirty-one issues remain pending. They concern equitable apportionment of water resources, prescriptive rights, and operational sharing during lean seasons. These are the subject matter of technical mediation by the CWC.
What is the technical assessment about?
A Common Format Information (CFI) system has been instituted to submit data as per a uniform format. It has 57 parameters covering land use, cropping patterns, hydro-meteorology, groundwater, industrial intake, lift irrigation schemes and delta requirements.
What are the main demands by Odisha?
In their complaint of November 2016, Odisha had kept the entire yield of 24 MAF generated in their own catchment outside adjudication, and had restricted adjudication to only the yield generated in Chhattisgarh catchment. Of this, they have sought about 15 MAF, which is more than two-thirds of the yield in Chhattisgarh. This would leave less than 8 MAF for Chhattisgarh, which is not sufficient to meet even the existing use by Chhattisgarh.
Why does Chhattisgarh seek a different basis for determining its share?
Chhattisgarh has sought apportionment of the yield of the entire basin, and not the yield only in Chhattisgarh, as per accepted norms of equitable apportionment.
What is Odisha's position on the existing arrangement?
Odisha has demanded a complete freeze on review. It does not want its current water consumption reassessed.
It seeks continuation of its historical utilisation at Hirakud, and some more.
What is Chhattisgarh's position?
Chhattisgarh argues that water utilization at Hirakud was planned without any consultations with the upstream areas, and without factoring in their future needs. In any case, nearly six decades have passed since the completion of Hirakud and a comprehensive review is necessary. Chhattisgarh asserts that as a riparian state, it too is entitled to an equitable share of the water resources of the basin.
It seeks an objective calculation of the 75% dependable yield across the entire basin and a legally binding reallocation based on accepted principles of equitable apportionment.
How has the latest round of mediation progressed?
Negotiated settlement efforts facilitated by the CWC began gaining momentum in mid-2025. The process continued with technical discussions and mediation in 2026. An opening mediation meeting was held on July 29, 2026.
The CWC subsequently issued data questionnaires to the two states on August 3 and August 21, 2026. The discussions have involved the technical issues that remain unresolved and the information required to examine them.
Did Chhattisgarh agree to the CWC's data formats?
Chhattisgarh complied with the initial data format but raised concerns over the scope of the CWC's requirements. It said the formats focused only on existing water use and already sanctioned projects, and did not cover growth projections and the criteria required for equitable apportionment.
What does Chhattisgarh want?
Chhattisgarh submitted its own independent datasets detailing its projected growth estimates, future water requirements, and proposed equitable sharing formula. The state said the submissions were intended to ensure that its developmental requirements were considered in the final settlement.
As per the 1947 report on the Hirakud dam project, it is categorically mentioned that no improvement and extension of delta irrigation has been considered in the Hirakud Dam Project. However, some delta irrigation demand from Hirakud is being met presently from Hirakud. Jayseelan Committee formed by Odisha Government in 2007 mentions agriculture demand of 1.59 MAF during the non-monsoon period of October-May for Delta-I and Delta-II schemes. This can be easily met from the yield of 20.52 MAF from downstream of Hirakud. If required, Odisha can be given a window of 10 years for shifting its downstream demand from Hirakud to downstream storage projects.
Further, the utilisation of 8.74 MAF for hydropower generation of only 359 MW from Hirakud in the present conditions is not justified, particularly when Odisha has identified close to 10,000 MW PSPs. Now many other sources of power generation are available, viz. wind and solar. Now, water is much more precious than electricity and by using these alternate sources of power generation, Odisha can save this water, which would be used for Chhattisgarh’s future demand, as Chhattisgarh has no option of extra water for its future growth.
What is the tribunal’s current deadline?
The tribunal's original statutory deadline to submit its report under Section 5(2) expired in March 2023 without a final ruling. The adjudication deadline has been extended to January 2027.
When do the stakeholders propose to meet over the issue?
The Advocate General of Odisha, Pitambar Acharya, said that Union Home Minister Amit Shah will chair a meeting of the chief ministers of Odisha and Chhattisgarh on Thursday, October 1, in a fresh bid to resolve the dispute.
What are the sticking points in the proposed settlement?
A framework for an amicable tripartite settlement is being formulated through CWC’s mediation.
The remaining issues include equitable apportionment, prescriptive rights and operational sharing during lean seasons, along with differences over future water requirements, evaporation losses, hydrology baselines, existing water use and the six barrages.