MULLAPERIYAR - SAVE 3 MILLION LIVES

A documentary by C-Dit on Mullaperiyar Dam. A "must see" 

for people of Kerala and Tamil Nadu.  

Dam failures are deadlier than Nuclear Bomb Explosions...

It was a night in August; Morvi town in Gujarat, India; was sleeping, families with their dear ones. Some people who were awake heard a big boom sound of the rushing water. Before they could realize the sound the entire town was flooded by the rushing water from the Morvi Dam.

The Morvi dam failure is the worst flood disaster to happen in independent India. On August 11, 1979, the Machchu-2 dam, situated on the Machhu, river burst and that sent a wall of water through the town of Morvi in Indian state of Gujarat killing 15000 people. It was caused by excessive rain and massive flooding. The spillway capacity provided for 5663 m³/s. But during the intense rainfall on that day became 16307 m³/s; 3 times what was designed - that caused the collapse of the dam. Within 20 minutes the floods of 12 to 30 ft height inundated the low-lying areas of Morvi industrial town located 5 km below the dam. During reconstruction of the dam the capacity of the spillway was increased by 4 times and fixed at about 21,000 m³/s. The town of Morvi is situated on the river Machhu, 35 kilometers from the sea and 60 kilometers from Rajkot.

Another August; the Banqiao Dam collapsed in China. The Dam was designed to survive a once-in-1000-years flood (300 mm of rainfall per day). In August 1975, however, a once-in-2000-years flood occurred, produced by the collision of tropical storm Nina and a cold front. More than a year's rainfall fell in 24 hours (new records were set, at 189.5 mm rainfall per hour and 1060 mm per day, exceeding the average annual precipitation of about 800 mm), which weather forecasts failed to predict. According to Beijing-based Central Meteorological Observatory the forecast was for rainfall of 100 mm. On August 6, a request to open the dam was rejected, because of the existing flood in downstream areas. On August 7, however, the request was accepted, but the telegrams failed to reach the dam.

The dam was completed on June 1952. The dam was made of clay and was 24.5 metres high. The maximum discharge of the reservoir was 1742 m³/s.Cracks in the dam and sluice gates appeared after completion due to construction and engineering errors. They were repaired with the advice from Soviet engineers and the new design, dubbed the iron dam, was considered unbreakable.

In August 1975; the sluice gates were not able to handle the overflow of water, partially due to sedimentation blockage. On August 7 at 21:30, the People's Liberation Army Unit which was deployed on the Banqiao Dam sent the first dam failure warning via telegraph. On August 8, 0:30, the smaller Shimantan Dam, designed to survive a 1-in-500-year flood, failed to handle more than twice its capacity and broke upstream, only 10 minutes after Unit 34450 sent a request that would open the Banqiao Dam by air strike. A half hour later, at 1:00, water at the Banqiao crested at the 117.94 m level above sea level, or 0.3 meter higher than the wave protection wall on the dam, and it too failed. This precipitated the failure of 62 dams in total. The runoff of Banqiao Dam was 13,000 m³ per second in vs. 78,800 m³ per second out, and 701 million m³ of water were released in 6 hours, while 1.67 billion m³ of water were released in 5.5 hours at upriver Shimantan Dam, and 15.738 billion m³ of water were released in total.

The resulting flood waters caused a large wave, 10 kilometers wide and 9.8–23 ft high to rush onto the plains below at nearly 50 kilometers per hour almost wiping out an area 55 kilometers long and 15 kilometers wide, and creating temporary lakes as large as 12,000 square kilometers. Seven townships were inundated, as were thousands of square kilometers of countryside and countless communities. Although a large number of people were reported lost at first, many of them returned home later. Tens of thousands of them were carried by the water to downriver provinces and many others fled from their homes. It has been reported that around 90,000 - 230,000 people were killed as a result of the dam breaking.

Nine days later there were still over a million people trapped by the waters, relying on airdrops of food and unreachable to disaster relief. Epidemics and famine devastated the trapped survivors. .

Dam failures are generally catastrophic if the structure is breached or significantly damaged. Routine deformation monitoring and monitoring of seepage from drains in and around larger dams is useful to anticipate any problems and permit remedial action to be taken before structural failure occurs. The main causes of dam failure include one in 1000 year flood, Earthquakes, Structural weakness and inadequate spillway capacity.

Mullaperiyar dam in Idukki district, Kerala, India is now in the news after the successive tremors in the area  during the month of November 2011 and also with the release of an English movie titled ‘999’ on 25^th November. The film is based on the award winning short documentary DAMs - The Lethal Water Bombs and the Banqiao dam disaster of 1975 that claimed the lives of 230,000 people in China. The movie also portrays a lost love against the backdrop of the story of a dilapidated colonial dam.

The Mullapperiyar dam was built in 1895 using lime surkhi morter; by the British Government. Now it is more than 116 years old. The useful life of a well-designed and well-built dam is generally considered to be about 50 to 60 years. Thus the dam has already exceeded its normal lifetime by 40 to 50 years. Earthquakes in the area have further highlighted safety issues and concerns over disastrous consequences of the dam bursting because of structure weaknesses and earthquake tremors with adverse impact on the lives and property of nearly 3 million people in Kerala.  

The name Mullaperiyar is derived from Mullayar and Periyar Rivers; hence the dam came to be called Mullaperiyar. The Dam is constructed at source of the Periyar River in Kerala, India. The Periyar National Park, Thekkady is located around the Periyar reservoir.

Historical background of the dispute

Periyar River is a west-flowing river of Kerala State. The river flow its full course entirely through Kerala, and derives its water exclusively from catchment area inside the State. The dam stops the west flowing river to form a reservoir, which is also exclusively located in Kerala. Tamil Nadu collects water to the eastern side of Western Ghats via a tunnel.

On 29-10-1886 a lease indenture for 999 years was made between Maharaja of Travancore and British Presidency of Madras. The lease indenture inter alia granted full right, power and liberty to construct, make and carry out on the leased land and to use exclusively when constructed, made and carried out all such irrigation works and other works ancillary thereto to Secretary of State for India (Now Tamil Nadu).

After Independence, both the entities became non-existent. Further, according to India Independence Act, 1947, all the treaties between British Government and Indian Princely States have lapsed. Article 131 of the Constitution barred enforcement of pre-constitutional agreements between princely States. Kerala argued that the agreement is not an equal one, but imposed on the local King by the mighty British Empire. Even in the absence of any treaties after independence, Tamil Nadu continued to use the water from Periyar for extending irrigation facilities, and later for power generation on the basis of informal agreements between the governments of the two states.

 In 1970 the Kerala and Tamil Nadu governments signed a formal agreement to renew the 1886 treaty almost completely for a period of 30 years, which lapsed in 2000. The Idukki Hydroelectric project, located 30 km downstream was completed in 1976 by the Kerala government is still the major resource for irrigation and electricity needs of Kerala. After Independence the areas downstream of the Mullaperiyar become heavily inhabited, as Kerala has a very high population density.

In 1979, safety concerns were raised by Kerala Government after a minor earthquake, after which a few leaks were detected in the Mullaperiyar dam. A state agency had reported that the structure would not withstand an earthquake above magnitude 6 on the Richter scale. The then Tamil Nadu government lowered the storage level to the current 136 feet (from 142.2 feet) at the request of the Kerala Government to carry out safety repairs, after which it was suggested that the storage level could be raised to the full reservoir level of 152 feet.

Meanwhile, the Tamil Nadu government had increased its withdrawal from the reservoir, with additional facilities to cater to the increased demand from newly irrigated areas. One article estimates that "the crop losses to Tamil Nadu, because of the reduction in the height of the dam, between 1980 and 2005 are a whopping Rs. 40,000 crores. In the process the farmers of the erstwhile rain shadow areas in Tamil Nadu who had started a thrice yearly cropping pattern had to go back to the bi-annual cropping.” But Kerala did not object giving water to Tamil Nadu. Their main cause of objection is the dam’s safety as it is as old as 116 years. Increasing the level would add more pressure to be handled by already leaking dam.

Security concerns regarding the downstream inhabitants prompted Kerala to backtrack on the 1970 Agreement in 2000. Another argument put forward by Kerala on the basis of a report on a study conducted state agencies suggested that the loss of habitat to the fauna of Periyar National Park would occur due to flooding after the increase in the storage level. IIT Delhi conducted a study which stated that the dam safety would be affected even at a level of 136 ft, IIT Roorkee conducted structural stability study on the Reservoir had found that the structure would not be safe in the event of an earthquake. In addition the Dam safety and Disaster management problems have assumed crucial importance in view of the recurring earthquakes and the frequent increases in the seepage of water through this aging dam.

The Dam is located 3900 feet above sea level on the High Ranges of Western Ghats in Thekkadi, Idukki District of Kerala. Earthquakes in the area have further highlighted safety issues and concerns over disastrous consequences of the dam bursting because of structure weaknesses and earthquake tremors with adverse impact on the lives and property of nearly 3.5 million people. Various issues are still being adjudicated by the Supreme Court of India. Mullaperiyar has been a hot issue politically and legally between the two Southern States of India, namely, Tamilnadu and Kerala.

The Periyar River originates in Kerala, and the major part of the catchment area falls within the state. If a proportional division of waters is done, Tamil Nadu will get zilch. If the dam bursts, they will be loosing the water sources now they are using.  It is the magnanimity of the people of Kerala that waters the arid plains of Theni. The people of Kerala do not want to stop the water transfer. They are not even demanding their fair share. They just want to live without the fear of the dam breach. If the dam burst, four districts in Kerala will be completely devastated and 3 million people perish. They are facing destruction right on the face. However, the Politicians of Tamil Nadu care nothing about the security of the lives of the people of Kerala. The gravity of the issue is rising with every passing day that could catapult to grave proportions.

The Mullaperiyar dam breach and the subsequent downstream flood may cause failure of Idukki arch dam, Cheruthani dam and Kulamavu dam. As a worst scenario, Arch dam or Cheruthoni dam failure flooding the Periyar, reaching Kochi from north through Neriamangalam, Thattekkad, Malayattoor, Cochin Airport and Aluva. Kulamavu dam break flooding Muvattupuzha River reaching Kochi from Vembanad, submerging Thodupuzha, Muvattupuzha, Piravam, Vaikam, Cherthala, and the entire Alappuzha district. There is no time to delay. Let us realize the impending danger before it is too late. Precautionary measures have to taken immediately to reduce the water level and to start the construction of the New Dam. If the breach happens, Kerala will not be the same after. Let wisdom dawn on the Politicians?