THE CONTROVERSY OVER MULLAPERIYAR DAM

THE CONTEXT:  In April 2022, the SC has given a slew of directions in the Mullaperiyar dam issue. The dam is at the center of a decades-old dispute: for Kerala, where it is situated, the dam presents a threat to lakhs living downstream; and for Tamil Nadu, which controls the dam, the water it provides is the lifeline of people in five districts. This article examines the controversy related to the dam in the light of the SC verdict.

ALL YOU WANT TO KNOW ABOUT MULLAPERIYAR DAM

The dam sits on the upper portions of the Periyar River, which originates in Tamil Nadu and goes into Kerala. Within the Periyar Tiger Reserve, the reservoir is located. The water diverted from the reservoir is used to generate electricity in Tamil Nadu’s lower Periyar region before flowing into the Suruliyar, a tributary of the Vaigai river, and then irrigating roughly 2.08 lakh hectares in Theni and four other districts farther afield.

WHAT IS THE CONTROVERSY?

HISTORICAL BACKGROUND:

  • The British administration regarded the Periyar waters useless to Travancore; thus the Maharaja of Travancore signed the ‘Periyar Lease Deed’ with the British government in 1886.
  • It intended to redirect the water to Tamil Nadu’s parched districts. After 20 years of defiance, the Maharaja signed the deal.
  • The dam was completed in 1895. In 1959, the Madras government began generating hydel power. The capacity was later raised to 140 MW.

CONCERNS FOR SAFETY:

  • Concerns about the dam’s safety stretch back to the early 1960s when the media stated that it was dangerous.
  • In 1961, Kerala brought the issue to the Central Water Commission’s attention. In 1964, the water level was dropped for the first time, from 155 feet to 152 feet, following a joint examination by Kerala and Tamil Nadu.
  • In the years that followed, Tamil Nadu witnessed public agitations demanding that the level be increased; Kerala opposed the demand.

STAND OF KERALA:

  • Kerala has been strongly advocating the need to decommission the “deteriorated” structure and build a new one.
  • It cited climate change-induced erratic and heavy rainfalls that could further damage the structure.
  • Political leaders of Kerala argue that the dam is a ticking time bomb that can explode at any moment, causing the deaths of thousands in the state.
  • It maintains that the only solution is razing down the existing weak structure and constructing a new dam.

STAND OF TAMIL NADU:

  • Meanwhile, Tamil Nadu considers it a safe and well-maintained dam and is making persistent efforts to raise the water storage level in it to 152 feet through interventions in Madras high court, Supreme Court, Central Water Commission, and other top bodies.
  • Tamil Nadu says water from the dam is vital to the arid villages and towns of the southern districts to address their drinking water and irrigation concerns.

BATTLE IN COURTS:

  • Over the years, petitions have been filed in the high courts of both states. These were subsequently transferred to the Supreme Court. In 2000, the Centre appointed an expert committee to look into safety and suggest storage levels. (Read Ahead).

A TIMELINE OF THE COURT BATTLE OVER MULLAPERIYAR DAM

2006:

  • The Supreme Court allowed Tamil Nadu to raise the water level to 142 ft.
  • It said after completing strengthening work, the level could be restored to 152 ft if an expert committee examined and recommended it.
  • In March 2006, the Kerala Assembly amended the Kerala Irrigation and Water Conservation Act, 2003, bringing Mullaperiyar into the ‘Endangered Dams’ schedule and restricting its storage at 136 ft.
  • Since then, the issue has shifted to the safety of the dam.

2007:

  • In 2007, the Kerala Cabinet permitted preliminary work on a new dam. Tamil Nadu approached the Supreme Court against the move.

2008:

  • In 2008, a flood routing study by IIT Delhi found the dam was unsafe, and in next year, IIT Roorkee reported the dam was in an earthquake-prone area and would not survive a major quake.

2010:

  • In 2010, the Supreme Court formed an empowered committee to look into the dam’s safety. As per the said order, the terms of reference of the Empowered  Committee were to:
  • Hear parties to the suit on all issues that will be raised before them, without being limited to the issues that have been raised before the Hon’ble Supreme Court, and furnish a report, as far as possible, within six months from their constitution.
  • The Committee shall frame its own procedure and issue appropriate directions as to the hearings as well as the venue of its sittings.
  • The Committee is free to receive such further evidence as it considers appropriate.
  • Legal and constitutional issues, including the validity of the Kerala Irrigation and Water Conservation (Amendment) Act, 2006 would be considered by the Hon’ble Supreme Court of India.

2011:

  • In November 2011, Kerala sought the Centre’s intervention to bring down water levels to 120 ft after the area witnessed minor tremors.

2014:

  • In 2014, the Supreme Court order allowed Tamil Nadu to fix the water level at 142 ft.

2018:

  • The Supreme Court directed Union Govt. to form a Sub-Committee under the National Executive Committee (NEC) of the National Disaster Management Authority (NDMA) to monitor the measures for ensuring a high level of preparedness to face any disaster in relation to Mullaperiyar Dam.

2021:

  • The SC directed Supervisory Committee on Mullaperiyar Dam to address three core issues i.e., the instrumentation plan of the dam, the rule curve & the gate operation schedule/reservoir operation plan.

2022:

  • On April 8, the Supreme Court reconstituted the Mullaperiyar dam’s supervisory Committee, including one technical expert each from Tamil Nadu and Kerala.
  • It gave the panel functions and powers comparable to those of the National Dam Safety Authority (NDSA), a body established under the Dam Safety Act of 2021.

THE SC ORDER IN A NUTSHELL

The court has enabled the supervisory Committee to deliberate on any pending concerns linked to the dam’s safety and undertake a new review of its safety and give it NDSA powers and functions. For any failure, “due to action” will be taken against the individuals involved, not only for violating the court’s orders, but also under the Act, which stipulates a year in prison or a fine, or both, for refusing to comply with the commands of entities established under the law. The two states are anticipated to nominate one representative each to the supervisory Committee and one nominee each, within two weeks, as ordered by the Supreme Court in its most recent ruling.

HOW REAL IS THE ENVIRONMENTAL THREAT?

UNITED NATIONS REPORT: 

  • A report prepared by the United Nations University-Institute for Water, Environment and Health, cited “significant structural flaws” in the dam and said it “may be at risk of failure”.
  • “Leaks and leaching are also concerning, as the methods and materials used during construction are considered outdated, compared to the current building standards, it said

IIT ROORKEE STUDY:

  • Commissioned by the Kerala Government in the latter part of the 2000s, a study by IIT-Roorkee raised questions about the survival of the dam, located in seismic zone-3, in the event of an earthquake of a fairly high magnitude.

TREMORS AND FLOODS:

  • Massive landslides had devastated central Kerala’s hilly regions, and weather prediction was ominous.
  • A series of tremors felt in the area in 2011 caused alarm. Subsequently, the floods of 2018 and the erratic nature of annual monsoons ever since brought the focus back on the 126-year-old dam.

THE CENTRAL WATER COMMISSION’S VIEW:

  • The Central Water Commission (CWC) informed the Supreme Court that a new review of the safety of Mullaperiyar is due.
  • In a status report before the apex court, CWC said that no review on safety was taken place for the last 12 years.
  • However, the same report quotes Empowered Committee constituted by the Supreme Court in 2010 that noted that Mullaperiyar was found to be safe in all respects, hydrologically, structurally, and seismically.

DO YOU KNOW?

A rule curve, also known as a rule level, indicates how much storage or empty space should be kept in a reservoir at different times of the year. It determines how a reservoir’s storage levels fluctuate. The rule curve is used to determine when a dam’s gates will open. It’s a part of a dam’s “core safety” mechanism. The TN government frequently blames Kerala for delaying the rule curve’s finalization.

THE WAY FORWARD:

DECENTRALISED STORAGE FACILITY:

  • The best solution is to construct a few smaller storage structures in the five districts of Tamil Nadu and divert the excess water from the dam to the storage.
  • A decentralised storage facility can avert the situation of keeping vast amounts of water in the 19th-century lime concrete structure.

NEW DAM IS NOT A FEASIBLE IDEA:

  • Constructing a new dam in the same seismic zone is dangerous. Decommissioning and construction activities would happen in a seismic zone that comes within a tiger reserve, known for rich biodiversity.
  • Given the experiences from different parts of the world, dam construction can heighten earthquake, landslide, and rockfall threats.
  • The huge human presence required for construction activities will kill the highly crucial Periyar Tiger Reserve surrounding Mullaperiyar.

CREATE DAM DEFORMATION DATABASE:

  • At present, there is very little dam deformation data in the case of Mullaperiyar.
  • The time requires the creation of an independent group of experts jointly by the two states to check existing technical reports and collect and analyse dam deformation data to decide on the dam’s future stability prospects.

WORK OF SUPERVISORY COMMITTEE:

  • The latest directions of the SC that empowered the Supervisory Committee to need to be implemented in letter and spirit, Both the states should provide all support for its work.

THE CONCLUSION: Political leadership of both the states needs to get their acts together for a viable solution to the dam issue. Science, data, and evidence need to drive the discourse that new technologies can speed up decision-making. The construction of a new dam carries risk. Hence, a decentralized approach to water management at the Tamil Nadu level and monitoring of the dam from the safety and structural aspects need to be undertaken.

Questions:

  1. What is the Mullaperiyar dam controversy? How far do you think constructing a new dam will resolve it?
  2. “ Without political solutions, judicial interventions fail” Comment in the light of the Mullaperiyar dam issue between Tamil Nadu and Kerala.