Mullaperiyar Dam

The Mullaperiyar Dam is a masonry gravity dam built over the Periyar River and its tributary, the Mullayar, in Kerala. It is situated in the Idukki district, on the Cardamom Hills of the Western Ghats. Located at the border of Kerala and Tamil Nadu, has been a long-standing source of dispute between the two states. The dam was built in the 19th century under a lease agreement made between the British administration and the Maharaja of Travancore. While the dam provides crucial irrigation and hydroelectric power benefits for Tamil Nadu, its safety has become a major concern for Kerala given the dam's advanced age. Kerala has sought revision of the original lease terms and raised objections to Tamil Nadu's efforts to increase the dam's water levels to improve utilization. Tamil Nadu insists on its water rights as per the original agreement. Various efforts have been made over the years to resolve the disputes, including legal petitions, expert committee reviews, and safety legislation like the Dam Safety Act 2021. The Supreme Court has also tried to find a balanced solution by allowing regulated raising of water levels by Tamil Nadu while mandating regular safety reviews. However, despite these interventions, the fundamental disputes over Mullaperiyar's lease terms and safety aspects persist between the two states.

1. A historical water-sharing agreement was signed between the Pandya kings of Madurai and the Travancore kingdom, which has become a point of disagreement between Kerala and Tamil Nadu today.
2. The British initiated the dam project to address the water scarcity and drought problems affecting people and agriculture in the Kingdom of Madurai.
3. The Cochin State ruler initially opposed the project, fearing it would disrupt the water flow and transportation on the Periyar River.
4. On 29 October 1886, a 999-year lease agreement was signed between the Maharaja of Travancore and the British Secretary of State for India, allowing the construction of the dam.
5. After India gained independence and the states were reorganized, the validity of the original agreement between the British Raj and Travancore was challenged by the Kerala state government, stating it needed renewal.

The Mullaperiyar Dam is a masonry gravity dam built over the Periyar River and its tributary, the Mullayar, in Kerala. It is situated in the Idukki district, on the Cardamom Hills of the Western Ghats. Completed in 1895, it stands as one of the oldest and largest dams of its kind in the country. The primary function of this dam is to support agriculture through irrigation in the Madras presidency (now Tamil Nadu). It also generates hydroelectric power and supplies water for drinking purposes.

• A masonry gravity dam is constructed using concrete and stone, relying on its own weight to stay anchored to the foundation. This design choice was common in the late 19th and early 20th centuries, primarily because it was more cost-effective compared to other dam types. However, the downside includes higher maintenance costs and a susceptibility to structural damage from seismic activity.

• Reservoir: Situated at the junction of the Mullayar and Periyar rivers in Kerala's Idukki district, the dam creates a reservoir. This reservoir is among the 3 major water sources for Tamil Nadu, boasting a capacity of 443,230,000 cubic meters.
• Located in Kerala, the dam is operated by Tamil Nadu

• After unsuccessful attempts in 1958, 1960, and 1969, the agreement for the Mullaperiyar Dam was finally renewed in 1970, during the tenure of Kerala’s Chief Minister, C Achutha Menon.
• The updated agreement included an increase in the tax per acre and set the electricity charge at ₹12 per kilowatt-hour for power generated using Mullaperiyar water at Lower Camp.
• For the past 50 years, the Tamil Nadu government has been paying Kerala an annual tax for the land and an additional surcharge for the electricity generated from the dam.

Early Influence

• The main problem discussed since 2009 is the danger that the old dam, which is 126 years old, could cause to Kerala's people if it breaks.
• Kerala’s suggestion to dismantle the old dam and build a new one has been opposed by Tamil Nadu.
• Tamil Nadu has accused Kerala of taking too long to decide on the rule curve for the dam. The rule curve is important because it sets how much water can be stored in the dam and when the dam's gates should be opened. It's a key part of keeping the dam safe. The level set by the rule curve helps to make sure that the dam's gates don't have to be opened suddenly during a flood. This is crucial for managing the water level in the dam when it rains a lot.
• What does Tamil Nadu have to say?
• Tamil Nadu says that even though it has worked to make the dam stronger, the Kerala government has stopped them from increasing the water level in the reservoir. This has caused problems for farmers in Madurai.

• For the first time in 35 years, in November 2014, the water in the dam reached 142 feet.
• After continuous heavy rain in Kerala, the dam filled up to its top capacity of 142 feet again in August 2018.
• Kerala believes the water in the dam should not go higher than 139 feet, matching the court's order on August 24, 2018, especially after floods hit the state. They say increasing the water level in the dam could put the lives of 50 lakh (5 million) people at risk. Tamil Nadu disagrees with this, mentioning Supreme Court rulings from 2006 and 2014 that allow the dam's water level to be up to 142 feet.

• The Supreme Court allowed the water storage level in the Mullaperiyar Dam to be increased to 142 feet, provided certain strengthening measures were completed, additional vents provided, and other recommendations implemented.
• Kerala's main concern was not the sharing of water with Tamil Nadu but the safety of the dam, which was over 110 years old at the time. Kerala was worried that raising the water level would put extra pressure on the already weakening structure.
• Tamil Nadu pushed for the implementation of the Supreme Court's 2006 order to increase the water level to 142 feet for better water availability.

• In response, Kerala passed the Kerala Irrigation and Water Conservation (Amendment) Act, 2006, aiming to protect all 'endangered' dams within the state, focusing on safety measures

• The Supreme Court established a five-member empowered committee led by Justice A.S Anand to thoroughly examine the Mullaperiyar Dam's condition and report back within six months.
• The committee concluded that the dam was structurally and hydrologically safe, allowing Tamil Nadu to raise the water level from 136 to 142 feet after necessary repairs were made.

• The Supreme Court ruled the Kerala Irrigation and Water Conservation (Amendment) Act, 2006 as unconstitutional. This decision permitted Tamil Nadu to increase the water level from 136 feet to 142 feet.
• Additionally, the court ordered the formation of a permanent Supervisory Committee to oversee and resolve issues related to the Mullaperiyar Dam, ensuring ongoing management and safety.

Rising Concerns

• In 2021, the safety of the Mullaperiyar Dam gained renewed attention due to the flood situation in Kerala since 2018 and the disaster at the Rishiganga hydroelectric project and Tapovan dam in Uttarakhand caused by a glacier burst, resulting in nearly 200 deaths.
• A report by the United Nations highlighted the risks posed by old dams worldwide, specifically mentioning the Mullaperiyar Dam's location in a seismically active zone, its significant structural issues, and the potential risk to 5 million people if the dam were to collapse.

The Dam Safety Act of 2021, effective from December 2021, represents a significant step towards enhancing the safety of major dams across India. It addresses the critical need for surveillance, inspection, operation, and maintenance of dams to prevent disasters resulting from their failure. The Act sets forth institutional measures to ensure dams are safely managed.

Rising Concerns

• Applicability: The Act covers inter-state dams taller than 15 meters and those between 10 to 15 meters under certain conditions.
• National Institutions: It establishes the National Committee on Dam Safety (NCDS) to develop safety policies and the National Dam Safety Authority (NDSA) as the regulatory body to enforce these policies and resolve inter-state dam safety issues.
• State-Level Institutions: The Act mandates the formation of State Dam Safety Organizations and State Committees on Dam Safety, assigning dam owners the responsibility for their dam's construction, operation, maintenance, and supervision.

• The Mullaperiyar Dam is specifically impacted by this Act because it is situated in Kerala but operated by Tamil Nadu, fitting the criterion for dams covered by the NDSA as those located in one state but utilized by another.
• The NDSA assumes the role of the State Dam Safety Organization for such inter-state dams, placing the Mullaperiyar under its jurisdiction.
• Additionally, the Supreme Court's suggestion to expand the powers of its monitoring committee to oversee the safety and maintenance of the Mullaperiyar Dam aligns with the objectives of the Dam Safety Act, potentially providing a more structured framework for managing the dam's safety concerns.

1. The Supreme Court received two petitions criticizing the ineffectiveness of the supervisory committee, established by the 2014 court order, over the last six years. The court demanded immediate action from Tamil Nadu's Chief Secretary regarding the dam's rule curve, warning of consequences for non-compliance.
2. The court held Tamil Nadu's Chief Secretary personally accountable for providing the rule curve information to the supervisory committee and mandated action against any failure to comply.
3. Additionally, the Supreme Court instructed the supervisory committee to tackle three primary safety concerns and to report back on compliance within four weeks.

• Monitoring the dam's instrumentation performance.
• Finalizing the rule curve.
• Establishing a schedule for operating the gates.

With technical and judicial efforts to resolve the Mullaperiyar Dam dispute largely exhausted, a political resolution is now seen as an important step towards an Friendly solution. Considering the potential risks involved, finding a solution is critical for the safety and well-being of millions.