The Supreme Court (SC) recently instructed the Mullaperiyar Dam Supervisory Committee to address various issues concerning the dam’s safety, thus renewing the ongoing friction over the dam between Tamil Nadu and Kerala. The SC formed a permanent Supervisory Committee in 2014 to oversee all matters related to the Mullaperiyar Dam.
Background
The case started with a petition filed by a resident of Idukki district in Kerala, urging for the water level in the Mullaperiyar Dam to be lowered to 130 feet. This was prompted by concerns over potential earthquakes and floods in the area as the monsoon season advances. The petitioner claimed that the Supervisory Committee had been “lethargical” about the dam’s safety inspection and survey, relegating its responsibilities to a sub-committee of local officials. For six years, there has not been any finalisation of the instrumentation scheme and safety mechanism.
Tamil Nadu’s Position
Tamil Nadu accused Kerala of slowing the finalisation of the rule curve for the dam, which is vital for determining fluctuating storage levels in a reservoir. The dam’s gate opening schedule is based on this rule curve, forming part of the “core safety” mechanism in a dam. This measure is set to prevent the emergency opening of dam shutters during flood-like situations, thereby controlling the water level during peak monsoon season. Tamil Nadu claims it has faced continual obstructions from Kerala in operating the dam, including lack of access to data located in Kerala’s terrain due to an absent road and unreplenished power supply.
Kerala’s Stand
Kerala countered by arguing that Tamil Nadu is maintaining an “obsolete” gate operation schedule that dates back to 1939.
Supreme Court’s Ruling
The court warned that the Tamil Nadu Chief Secretary would be held “personally responsible” and face “appropriate action” if the Supervisory Committee does not receive information on the rule curve for the Mullaperiyar Dam. The court also mandated the Supervisory Committee to address three central safety concerns and submit a compliance report within four weeks.
Core Safety Concerns
The committee has been tasked with monitoring and evaluating the dam’s instrumentation, finalising the rule curve, and determining the gate operating schedule. These three concerns directly impact the dam’s safety and could potentially affect individuals living in nearby areas.
About the Mullaperiyar Dam
The 123-year-old Mullaperiyar Dam is situated at the junction of the Mullayar and Periyar rivers in Kerala’s Idukki district. With a length of 365.85 meters and a height of 53.66 meters, the dam is operated and maintained by Tamil Nadu to satisfy the drinking water and irrigation needs of its five southern districts. This right was granted to Tamil Nadu as per a 999-year lease agreement made during the British rule. The dam is designed to divert the waters of the west-flowing river Periyar to the arid rain-shadow regions of Tamil Nadu.
The Periyar River
The Periyar River, often referred to as the ‘Lifeline of Kerala’, is the longest river in Kerala, stretching across 244 km. It is one of the few perennial rivers in the state, boasting continuous flow in parts of its stream bed throughout the year. The river branches out from the Sivagiri hills of Western Ghats and moves through the Periyar National Park. Its major tributaries include Muthirapuzha, Mullayar, Cheruthoni, and Perinjankutti.
