Mullaperiyar is a 111 year old dam, leaking from head to tail, on the upper reaches of the Periyar dam in Idukki district of Kerala State, India. It is in an alarming condition as the rising level of the water in the dam can endanger the lives of more than 2.5 million people living in about 5 districts in the state. This probable disaster can turn into a reality any time. This may be the first time that Mother Nature is giving us a chance to react to her fury. But this has been consistently put on the back burner by the many governments that have come and gone. Mainly because the main benefactor of the dam, the neighboring state of Tamil Nadu, has forcefully resisted any attempt to mitigate the disastrous conditions prevailing for over 50 years. It is not a dispute on the release of water to the neighboring state but a question of the lives of millions of people who may be sent to a watery grave.

 

There have been about 2000 dam failures in the world since the 12th century but nothing can top that which can happen at Mullaperiyar. Even more modern dam’s built using more scientific and advanced engineering have collapsed causing millions of dollars of damage and above all loss of human lives. 

 

Facts about the Mullaperiyar dam:

 

The dam is 111 years old and has outlived its life expectancy of 50 years considering the technology and material used for its construction in those days. The dam is not structurally sound and was build using crude lime surki mortar. The thickness at the top is 3.66 meters and the bottom is 44.2 meters. The height is 53.64 meters with a capacity of 15.6 TMC (443.23 million cubic meters)
The main beneficiary of the dam is not the people of Kerala but rather the neighboring state of Tamil Nadu which is dependent on the dam for Irrigation and the production of electricity. Even with the alarming state of affairs the Tamil Nadu state has been demanding an increase in the water level to 142 ft, the pressure which the dam will not be able to withstand.
The dam was constructed using lime surki mortar (a primitive technology) and the British engineer who constructed this dam had predicted its life span of just 50 years. This concrete is graded at M5 strength as compared to M30 strength that is generally used to build dams today, which has about 6 times the strength. The leaching of the lime is also a factor for the deterioration of the dam.
Further more no drilling and grouting were done to strengthen the foundation of the dam.
No drainage gallery was provided in the dam body. And transverse contraction joints were not provided in the dam.
Landslides, floods and torrential rains are common in this state of India which can cause high tidal waves which can all potentially lead to the collapse of the dam. And global warming has raised the incidents of these untimely rains and floods. Point to note here is that 40% of all dam failures in the world have been due to floods.
The lease agreement was forced upon the princely state of Travancore by the then Madras government for an unheard of period of 999 years with the help of the mighty British Empire 65 years prior to the independence of India. There have been a number of blatant violations of the agreement at various points in history, without any proper arbitration, including the use of the water from the dam for hydro-electricity.
Almost 70 TMC of water is released to Tamil Nadu (TN) every year. TN pays the Andhra Pradesh government Rs. 30 million for 1 TMC of water whereas they pay the Kerala government a measly Rs 571 for 1 TMC of water. The TN government’s revenue from hydro-electricity exceeds Rs. 7 trillion a year. These are major factors as to why the TN government is resisting any attempt to even evaluate the safety of the dam. If a new dam were to be built the contract would have to be re-negotiated which most likely will not be so favorable for TN government.
Despite certified claims to strengthen the dam in 1979 and lower the water level till then, there has been very little done except cosmetic fixes and the leakage continues even to this day, even more severely.
The dam is located in a seismic zone and the dam is not strong enough to withstand an earthquake of more than 6.0 on the Richter scale. A study by the Earth Sciences group along with the Indian Institute of Science has shown this and also the strong possibility of earthquakes of this magnitude in the area.
The nearby Baby dam is also in a very bad shape. Another dam downstream, the Idukki dam which is Kerala’s largest water reservoir will not be able to withstand the pressure of the gushing water if something untoward were to happen to the Mullaperiyar dam upstream. The Idukki dam has also lost its ‘elasticity’ in recent years, which is a shortcoming of most concrete dams. The collapse of the Mullaperiyar dam will result in the collapse of a number of dam’s downstream including the Idukki dam with un-imaginable consequences for the people in its path.
In 1975 the collapse of the Banqiao in China following heavy rains and floods caused the collapse of many dams and claimed the lives of over 250,000. If the Mullaperiyar dams collapse it will lead to the collapse of at least four dams downstream and the death toll will be more than 10 times than that caused by the Banqiao dam disaster. These two dams have almost the same capacity but the Banqiao dam was situated at an elevation of 118 meters but the Mullaperiyar dam is perched at an elevation of 873 meters which increases the gravitational potential energy of the outflow by 7 folds.
In case of a disaster the water will rush like a bullet due to the steep hilly geographical position of the dam to reach the Arabian Sea 100 km away in less than 1 hour through the thickly populated areas downstream.
It has been scientifically proven that the potential energy of the water stored in this dam is 180 times the energy released in the nuclear bomb explosion in Hiroshima.
The only option is to build a new dam and in the meanwhile reduce the water level to less than 136 ft. But the Tamil Nadu government has, with the help of the Central government, even banned the examination of the dam’s structural damages by the Indian Navy.
 

Tsunami and earthquakes in the past have come without warning. But this is a disaster that is completely preventable if the politicians and government bureaucrats of India wake up and take the issue in all its seriousness. The people of the state, especially those in the surrounding areas constantly live in a state of panic with an ever imminent disaster glooming over their heads like the sword of Damocles.

 

We may not have another chance to prevent this disaster.