Gist of the matter is just three points

  1. Tamilnadu operates the dam in Kerala. wants to increase water level in it.
  2. Kerala worries that dam will get destroyed anytime soon due to old age or earthquake. Hence enacted a law to decrease water level in it.
  3. Supreme court says Kerala law is wrong, Tamilnadu is right.

What is MullaperyarDam?

  • Type: a masonry gravity dam.
  • River: confluence of Periyar river and Mullayar river
  • place: Thekkady, Kerala. The dam site is in Kerala but is leased to TN
  • Provides irrigation to South Tamil Nadu (~2 lakh acres)
  • Periyar river originates from Ananamalai Hills and Joins sea near Ernakulam
  • TN has right to utilise and maintain the dam.

Map Mullaperiyar dam

Timeline: of the Mullaperiyar dam:
  • The British (Madras presidency) built Mullaperiyar dam with a lease agreement with Kingdom of Travancore for 999 years.
1970 Governments of Kerala and Tamilnadu ratified this agreement.

Why controversy:

  • In mid-70s, Kerala became worried about leakage from the dam and wanted Tamilnadu to repair it.
  • Kerala govt. communicated with union.
  • Union government directed Tamilnadu state government to
    • Repair this dam.
    • Keep water level in the dam at 145 feet.
  • Now, Union believed there is no longer any danger to the structure.
  • 2006: SC allowed Tamilandu to raise water height to 152 feet after strengthening the dam. (Total height of the dam is 176 feet).
  • But Kerala passed a law the Kerala Irrigation and Water Conservation (Amendment) Act, 2006, to prevent the neighboring State (TN) from raising the water level beyond 136 feet.
  • Tamilnadu challenged Kerala’s dam height law in Supreme court.

Graph Mullaperiyar dam height

Kerala’s stand Tamilnadu’s stand
  • if Mullaperiyar dam gets destroyed, it will also damage its Idduki dam down the course
  • Idduki is the largest source of hydroelectricity in Kerala
  • The broken Mullaperiyar dam can also damage Periyar National park and Periyar tiger reserve.
Without raising water level in this dam, we cannot sustain our agriculture and drinking water requirement.
this 119 year old dam poses danger to life and property nearly 4 million people downstream We’ve done adequate work to strengthen the dam structure.
There was a minor earthquake near dam site. Infact, we want to reduce water level further to 120 feet. Tremors were very minor. No danger to dam.
2010: Kerala demanded that entire dam be dismantled and we construct a new, stronger dam. (Kerala was ready to pay entire expense) Disagreed. For it’ll take lot time to setup new dam, what about the farm-irrigation in the meantime?

2010: Justice Anand Committee says dam is safe. Mullaperiyar dam poses no danger to idduki dam.
May 2014: Supreme Court order

  • Kerala dam Law of 2006 is unconstitutional and void.
  • Because Mullaperiyar is a dispute between two states. In such disputes, one state legislature cannot unilaterally enact law in its own favor.
  • Besides, in 2006 we had allowed Tamilandu to raise water height. By enacting g this law, Kerala is interfering with our judicial function.
  • Permitted Tamilnadu to increase water level upto 142 feet. (present ~136ft)

June 2014:

  • Union government decided to setup a Committee to supervise this water rising.
  • Kerala planning to file a review petition in SC.
  • Kerala assembly requested President of India to refer the matter to the Supreme Court under Article 143

Mock Questions

Q1. Consider following statements about Mullaperiyar dam

  1. it’s built on the Mullaperiyar river which originates from Annamallai hills
  2. At present, Tamilnadu owns and operates the dam
  3. Maharaja of Travancore had built this dam by taking a lease from Madras presidency.

The incorrect statements are

  1. only 1 and 2
  2. only 2 and 3
  3. only 1 and 3
  4. none of them

Q2. Which of the following is a plausible way to resolve Mullaperiyar dam controversy

  1. If Tamilnadu pays electricity tax dues to Kerala state government, for using the hydroelectricity of Mullaperiyar dam
  2. If Tamilnadu pays compensation to displaced Keralites living in the upstream, before increasing the height of this dam
  3. If Tamilnadu agrees to divert part of the water from this dam to Kerala farmers in Idduki and other downstream regions.
  4. None of them

Interview Question: What is the controversy surrounding Mullaperiyar dam? What is SC’s latest judgment on it? What is the permanent solution to this issue?

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