Tamil Nadu Accuses Kerala of Dam Safety Obstruction in Supreme Court

The government of Tamil Nadu has approached the Supreme Court to highlight what it describes as Kerala's "obstructionist attitude" in the Mullaperiyar dam dispute. This complaint centers on the stalled implementation of a 2014 apex court ruling that permitted Tamil Nadu to raise the reservoir's water level to 142 feet.

The Mullaperiyar Dam, a 131-year-old structure located in Kerala's Idukki district but owned and operated by Tamil Nadu, has been the subject of a long-standing dispute. In May 2014, a Constitution Bench of the Supreme Court deemed the dam structurally sound and authorized Tamil Nadu to increase the water level from 136 feet to 142 feet. A subsequent 2006 judgment had even allowed for a potential rise to 152 feet after structural strengthening.

Key Facts

• Tamil Nadu has filed a complaint in the Supreme Court against Kerala regarding the Mullaperiyar Dam.
• The complaint alleges Kerala is exhibiting an "obstructionist attitude" that has stalled the implementation of a May 7, 2014 Supreme Court judgment.
• The 2014 judgment permitted Tamil Nadu to raise the Mullaperiyar Dam's water level to 142 feet.
• Tamil Nadu asserts that Kerala has not cooperated with necessary strengthening measures for the baby dam, earth dam, and grouting of the main dam.
• The state seeks permission to fell trees near the dam site for safety and strengthening work.
• Tamil Nadu also requested permission to complete grouting works on the dam.
• The Mullaperiyar Dam, constructed in 1895, is located in Idukki district, Kerala, and is owned and operated by Tamil Nadu.
• A 2006 court judgment had allowed Tamil Nadu to potentially raise the water level to 152 feet after structural strengthening.
• Tamil Nadu reported to the court in August 2026 that a statement made by Kerala's counsel on July 31, 2025, regarding necessary permissions was contrary to the facts.
• Tamil Nadu accused Kerala of delaying permission for transporting grouting materials and machinery.
• Kerala had requested an initial deposit of ₹87,64,000 in November 2025 for repairs to the approach road, for which Tamil Nadu granted administrative sanction in February of the current year, but Kerala had not started work.
• Action is pending on the preparation of an Emergency Action Plan (EAP) based on terms of reference and hazard classification shared by the National Dam Safety Authority in May of the previous year.
• Kerala has not yet shared real-time rainfall/flood data for inflow forecasting for the Mullaperiyar dam's catchment area.