Chennai: The long-standing dispute between Tamil Nadu and Kerala over the Mullaperiyar Dam has once again come into focus after the Tamil Nadu government announced in its 2026 to 2027 state budget that it would continue efforts to raise the dam's water level to its original full-reservoir level of 152 feet. The announcement reaffirms the state's long held position that increasing the storage capacity is essential for meeting the water needs of millions of people in southern Tamil Nadu.
The proposal was made during the presentation of the Tamil Nadu budget, where the government said it would continue to pursue legal and technical measures to restore the dam to its original storage level. The state also reiterated its commitment to carrying out maintenance and strengthening works at the dam while protecting its rights under existing agreements and Supreme Court rulings.
The Mullaperiyar Dam, situated in Kerala's Idukki district, is operated and maintained by Tamil Nadu under a lease agreement that dates back to 1886 during the British era. The agreement was revised in 1970, but the ownership and operation of the dam have remained a sensitive issue between the two neighbouring states for decades.
Tamil Nadu has consistently argued that raising the water level is necessary to ensure sufficient water supply for irrigation and drinking purposes. Water from the reservoir is diverted through a tunnel into Tamil Nadu, where it supports agriculture and provides drinking water in districts such as Theni, Madurai, Dindigul, Sivaganga and Ramanathapuram. According to the state government, restoring the water level to 152 feet would significantly improve water availability, especially during periods of low rainfall.
Kerala, however, has repeatedly expressed concerns over the safety of the ageing masonry dam, which is more than 130 years old. The state maintains that increasing the water level could pose a serious risk to people living downstream in the event of structural failure. Kerala has consistently advocated for the construction of a new dam while assuring that it has no objection to supplying water to Tamil Nadu under existing arrangements.
The issue has been the subject of several legal battles over the years. In a landmark judgment delivered in 2014, the Supreme Court allowed Tamil Nadu to raise the water level from 136 feet to 142 feet after strengthening measures were completed. The court also struck down a Kerala law that had limited the storage level to 136 feet. However, the court made it clear that any move to increase the level beyond 142 feet would depend on the completion of further strengthening works and the necessary technical assessments.
As things stand, the maximum permitted storage level remains 142 feet. Although Tamil Nadu's latest budget announcement highlights its intention to eventually reach 152 feet, it does not mean the water level will be increased immediately. Any future increase would require compliance with legal procedures, engineering evaluations and regulatory approvals.
Recent official data show that the current water level in the reservoir is well below the permitted limit, standing at around 116 feet in early August. The reservoir continues to be monitored regularly, with maintenance and safety inspections carried out under the supervision of the relevant authorities.
The latest announcement is expected to revive political discussions between the two states, where the issue has often become a major topic during elections and legislative sessions. While Tamil Nadu continues to stress its need for additional water storage, Kerala remains firm that public safety must remain the highest priority.
Despite the renewed debate, there has been no fresh change in the legal status of the dam. The current operational limit of 142 feet remains in force, and the proposal announced in the Tamil Nadu budget represents a policy objective rather than an immediate administrative decision.
The Mullaperiyar dispute remains one of India's longest-running interstate river water issues, balancing the competing priorities of water security, agriculture, legal rights, and public safety. With both states standing by their established positions, the matter is likely to remain a significant political and legal issue in the years ahead.