Why in news?

Tamil Nadu has accused Kerala in the Supreme Court of complaining about the safety of the Mullaperiyar dam but blocking necessary maintenance work on the dam. It contended that Kerala has managed to delay even routine annual maintenance works, including painting, patch works, repair to staff quarters, etc., for two months to more than a year.

Tamil Nadu asked the court to tell Kerala to let them finish strengthening work on the smaller dams and the main dam, and to cut 15 trees for this.

The State also said that even though the supervisory committee had authority under the Dam Safety Act, 2021, it didn't make sure Kerala allowed and helped with the dam's strengthening and related works.

What’s in today’s article?

• Mullaperiyar Dam Issue
• Provisions for the distribution of water in Indian Constitution
• Dam Safety Act and Mullaperiyar dam

Mullaperiyar Dam Issue

About the dam:

• 
• The dam is situated at the confluence of the Mullayar and Periyar rivers.
  • The dam is located entirely in Kerala.
• It was built in the late 1800s in the princely state of Travancore (present-day Kerala) and given to British-ruled Madras Presidency on a 999-year lease in 1886.
  • The agreement granted full rights to the Tamil Nadu to construct irrigation projects on the land.
• The dam was built to divert eastwards a part of the west-flowing Periyar river, to feed the arid areas of Tamil Nadu.

Situation after Independence

• After the independence, the Kerala government said that the earlier agreement signed between British Raj and Travancore was invalid and needed to be renewed.
• As a result, the agreement was renewed in the 1970s.
  • Tamil Nadu was given rights to the land and the water from the dam as well as the authority to develop hydro-power projects at the site.
  • Kerala received rent in return.

Origin of the dispute:

• Safety concerns surfaced in 1979 after it was reported in the Kerala that a minor earthquake had caused cracks in the dam.
• The Central Water Commission was asked to examine the structure and suggest ways to strengthen it.
  • As an emergency measure, the commission recommended that the level of water stored in the reservoir be lowered to 136 feet from about 142 feet.
  • It held that the water level could be raised to the dam’s full capacity of 152 feet after the structure was strengthened.
• This caused two divergent perspectives leading to the emergence of dispute between these two states:
  • Tamil Nadu claims that though it has undertaken periodic repairs on the dam, the Kerala government has not allowed it to raise the water level.
  • Kerala, on the other hand, contends it is not safe to raise the water level as Idukki district, where the dam is located, is earthquake-prone.

Supreme Court Judgement

• In 2006, the Supreme Court allowed the Tamil Nadu government to raise the water level to 142 feet, contending that the apprehensions raised by Kerala were baseless.
  • The Kerala government countered this with an amendment to the 2003 Kerala Irrigation and Water Conservation Act.
  • The amendment classified the Mullaperiyar dam as endangered and restricted the level of water in it to 136 feet.
    • This amendment was declared unconstitutional by the SC in 2014.
  • In 2014, SC said that Kerala could not obstruct Tamil Nadu from raising the water level to 142 feet.
  • To allay Kerala’s concerns, it directed that a three-member supervisory committee be set up to:
    • oversee the process of raising the water level,
    • inspect the dam routinely, and
    • look into the safety concerns.

Provisions for the distribution of water in Indian Constitution

• The relevant provisions of the Indian Constitution are
  • Entry 17 in the State List,
  • Entry 56 in the Union List, and
  • Article 262

Dam Safety Act and Mullaperiyar dam

• About the act
  • The act is aimed at addressing the long-felt need for addressing issues concerning the safety of major dams all over the country.
    • The act came into force in December 2021.
  • It provides for surveillance, inspection, operation, and maintenance of certain dams for prevention of disasters related to dam failure.
  • It also creates institutional mechanisms to ensure their safe functioning.
• Key provisions of the act:
  • The Act covers those dams having a height of over 15m and between 10m and 15m with certain stipulations.
  • It seeks to create two national institutions—
    • National Committee on Dam Safety (NCDS) to evolve dam safety policies and recommend necessary regulations, and
    • the National Dam Safety Authority (NDSA) to implement policies and address unresolved issues between the two States.
  • The NDSA will be the regulatory body.
  • The legislation also envisages the formation of State Dam Safety Organisations and State Committees on Dam Safety.
  • Dam owners will be held responsible for the construction, operation, maintenance, and supervision of dams.
• Linkages between Dam Safety Act and the Mullaperiyar dam
  • As per the Act, the NDSA will perform the role of the State Dam Safety Organisation for a dam located in one State and used by another.
  • Hence, the Mullaperiyar dam comes under the purview of the NDSA.
  • Experts believe that there is every possibility of the Union government will indicate in the court that the NDSA can subsume the functions of the supervisory committee.