#GS-03 Disaster Management, #GS-02 Inter-State Disputes
- Mullaperiyar dam is a 126-year-old dam located on the confluence of the Mullayar and Periyar rivers in Kerala’s Idukki
- The dam though fully located within Kerala, is owned, operated and maintained by Tamil Nadu.
- This agreement was reached due to a lease indenture for 999 years (the Periyar Lake Lease Agreement) signed between the Maharaja of Travancore and the Secretary of State for India for the Periyar Irrigation works in 1886.
- The dam was constructed between 1887 and 1895 and is used to redirect water to the Bay of Bengal, instead of the Arabian Sea.
- The dam is a major source of irrigation and drinking water to the arid rain shadow regions of Theni, Madurai, Sivaganga, Dindigul and Ramnad districts.
- The dispute originated in 1979 over the safety of the dam due to its location in an earthquake prone region.
- As the result of the dispute, a tripartite meeting under the chairmanship of the then head of the Central Water Commission, C. Thomas was held in November 1979.
- It was decided in this meeting, that water level had to be reduced from the full reservoir level of 152 ft to 136 ft, in order to enable Tamil Nadu to carry out dam strengthening works.
- This was completed by the mid-1990s and Tamil Nadu started demanding restoration of the water level.
- Failure to reach a consensus on the issue resulted in both parties approaching the Supreme Court.
- Supreme Court in two separate judgements, in 2006 and 2014, held that the water level be raised to 142 ft.