Mullaperiyar Dam

 The Mullaperiyar Dam is a gravity dam made with limestone and surkhi (a mixture of crushed brick, sugar and quicklime) on the Periyar River. It is located 881 m (2,890 ft) above mean sea level on the Cardamom Hills of the Western Ghats in Thekkady, Idukki District of Kerala. It was constructed between 1887 and 1895 by the British Government to divert water eastwards to Madras Presidency area (the present-day Tamil Nadu). It has a height of 53.6 m (176 ft) from the foundation and length of 365.7 m (1,200 ft).The dam and the river are owned by and located in Kerala but the dam is controlled and operated under a period lease by neighboring Tamil Nadu state.

       The safety of the dam has been a matter of concern and a point of dispute between Kerala and Tamil Nadu States. The present name Mullaperiyar is derived from an integration of Mullayar River and Periyar River. On 29 October 1886, a lease agreement for 999 years was made between the Maharaja of Travancore, Visakham Thirunal Rama Varma and the British Secretary of State for India for Periyar Irrigation Works. The lease provided the British the rights over "all the waters" of the Mullaperiyar and its catchment basin, for an annual rent of 40,000.

Safety Concerns

After the 1979 Morvi Dam failure which killed up to 25,000 people safety concerns of the aging Mullaperiyar dam's leaks and cracks were raised by Kerala Government. A State agency, Centre for Earth Science Studies (CESS), Thiruvananthapuram, had reported that the structure would not withstand an earthquake above magnitude 6 on the Richter scale

Risk and threat Factors

a. Age of the dam: The dam is 116 years old as of 2011. It has outlived its expected life span of 50 years. b. Elevation of the dam: The dam is situated approx. 3000 ft above msl and holds 15 tmc of water at full capacity (at 155 feet water level). The gravitational potential energy of the dam under these conditions is 3000 million joules. The height of the water column is 155 feet at full capacity and 1200 ft length at the crest. The damage that such a water mass can cause, in the event of a dam failure, is disastrous. C. Structural weaknesses: The dam was constructed using stone ruble masonry with lime mortar grouting following prevailing 19th century construction techniques that have now become archaic. Seepage and leaks from the dam have caused concern.d. Earthquakes: The dam is situated in a seismically active zone. e. Floods: Global warming and changing weather patterns leading to torrential rains and flooding can lead to overflow and collapse of the dam. f. Safety maintenance and safety monitoring of the dam ; Continuous safety monitoring is required to prevent disasters and to detect dam failure.

B- Adverse impact of dam collapse

Loss of human life and property by catastrophic flooding, loss of flora and fauna including identified endangered species in the Periyar Wildlife Sanctuary, loss of tourism, domino effect of collapse of Idukki Dam and the disastrous consequences of an Idukki Dam disaster, loss of agriculture irrigation, drinking water supply and power generation in southern Tamilnadu and huge impact on the general economy of Kerala and Tamilnadu. This includes large unbudgeted private and public expenses of flood cleanup, rebuilding the economy, and loss of human life and property of three districts of Kerala, loss of agriculture irrigation, drinking water supply and power generation in southern Tamilnadu, and a huge impact on the general economy of Kerala and Tamilnadu.

Interstate dispute

Now the mullaperiyar dam issue became an inter-state dispute, The Supreme Court of India appointed a five member committee headed by Justice A.S. Anand on 18 February2010,to go into all issues relating to the dam's safety and the storage level and seek a report from it within six months. The Bench in its draft order said Tamil Nadu and Kerala would have the option to nominate a member each, who could be either a retired judge or a technical expert However, the then ruling party of Tamil Nadu, DMK, passed a resolution that it not only oppose the apex court's decision to form the five-member committee, but also said that the state government will not nominate any member to it.As per the opinion of Chief Minister of Kerala, we did not object giving water to Tamil Nadu, but main cause of objection is the dam’s safety as it is as old as 110 years. Increasing the level would add more pressure to be handled by already leaking dam. Tamil Nadu wants the 2006 order of Supreme court be implemented so as to increase the water level to 142 feet (43 m).