Mullaperiyar Dam


Mullaperiyar Dam is a masonry gravity dam on the Periyar River in the Indian state of Kerala It is located above mean sea level, on the Cardamom Hills of the Western Ghats in Thekkady, Idukki District of Kerala, South India. It was constructed between 1887 and 1895 by John Pennycuick and also reached in an agreement to divert water eastwards to the Madras Presidency area. It has a height of from the foundation, and a length of. The Periyar National Park in Thekkady is located around the dam's reservoir. The dam is built at the confluence of Mullayar and Periyar rivers. The dam is located in Kerala on the river Periyar, but is operated and maintained by the neighbouring state of Tamil Nadu. Although the Periyar River has a total catchment area of 5398 km2 with 114 km2 downstream from the dam in Tamil Nadu, the catchment area of the Mullaperiyar Dam itself lies entirely in Kerala and thus not an inter-State river. However, by the principle of estoppel it is considered otherwise. On 21 November 2014, the water level hit 142 feet for first time in 35 years. The reservoir again hit the maximum limit of 142 feet on 15 August 2018, following incessant rains in the state of Kerala.

Etymology

Earlier known as the Periyaru Dam as it was basically meant to dam the Periyaru river, the present name Mullaperiyar is derived by vaguely blending the names of Mullayar River and Periyaru River, at the confluence of which the dam is located below.

Purpose

The Periyaru river which flows westward of Kerala in to the Arabian sea was diverted eastwards to flow towards the Bay of Bengal to provide water to the arid rain shadow region of Madurai in Madras Presidency which was in dire need of a greater supply of water than the small Vaigai River could provide. The dam created the Periyar Thekkady reservoir, from which water was diverted eastwards via a tunnel to augment the small flow of the Vaigai River. The Vaigai was dammed by the Vaigai Dam to provide a source for irrigating large tracts around Madurai. Initially the dam waters were used only for the irrigation of.
Currently, the water from the Periyaru Lake created by the dam, is diverted through the water shed cutting and a tunnel to Forebay Dam near Kumily. From the Forebay dam, hydel pipe lines carry the water to the Periyar Power Station in Lower Periyaru. This is used for power generation in the Periyar Power Station. From the Periyar Power Station, the water is let out into Vairavanar river and then to Suruliyar and from Suruliyar to Vaigai Dam.

Design

The Mullaperiyar Dam is a gravity dam made with concrete prepared from limestone and "surkhi", and faced with rubble. Gravity dams use their weight and the force of gravity to support the reservoir and remain stable. The main dam has a maximum height of and length of. Its crest is wide while the base has a width of. It consists of a main dam, spillway on its left and an auxiliary dam to the right. Its reservoir can withhold of water, of which is active storage.

History

Feasibility studies

The unique idea of harnessing the westward flowing water of the Periyar river and diverting it to the eastward flowing Vaigai river was first explored in 1789 by Pradani Muthirulappa Pillai, a minister of the Ramnad king Muthuramalinga Sethupathy, who gave it up as he found it to be expensive. The location of the dam had first been scouted by Captain J. L. Caldwell, Madras Engineers in 1808 to reconnoitre the feasibility of providing water from the Periyar river to Madurai by a tunnel through the mountains. Caldwell discovered that the excavation needed would be in excess of 100 feet in depth and the project was abandoned with the comment in his report as "decidedly chimerical and unworthy of any further regard".
The first attempt at damming the Periyaar with an earthen dam in 1850 was given up due to demands for higher wages by the labour citing unhealthy living conditions. The proposal was resubmitted a number of times and in 1862, Captain J. G. Ryves, M.E., carried out a study and submitted proposals in 1867 for another earthwork dam, 62 feet high. The matter was debated by the Madras Government and the matter further delayed by the terrible famine of 1876–77. Finally, in 1882, the construction of the dam was approved and Major John Pennycuick, M.E., placed in charge to prepare a revised project and estimate which was approved in 1884 by his superiors.

Lease

On 29 October 1886, a lease indenture 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 agreement was signed by Dewan of Travancore V Ram Iyengar and State Secretary of Madras State J C Hannington. This lease was made after 24 years negotiation between the Maharaja and the British. The lease indenture granted full right, power and liberty to the Secretary of State for India 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. The agreement gave 8000 acres of land for the reservoir and another 100 acres to construct the dam. The tax for each acre was 5 per year. 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.
In 1947, after Indian Independence, after British India was partitioned in 1947 into India and Pakistan, Travancore and Cochin joined the Union of India and on 1 July 1949 were merged to form Travancore-Cochin. On 1 January 1950, Travancore-Cochin was recognised as a state. The Madras Presidency was organised to form Madras State in 1947.
On 1 November 1956, the state of Kerala was formed by the States Reorganisation Act merging the Malabar district, Travancore-Cochin, and the taluk of Kasargod, South Canara. The Kerala state government announced that the earlier agreement which had been signed between British Raj and Travancore agreement was invalid and needed to be renewed.
After several failed attempts to renew the agreement in 1958, 1960, and 1969, the agreement was renewed in 1970 when C Achutha Menon was Kerala Chief Minister. According to the renewed agreement, the tax per acre was increased to 30, and for the electricity generated in Lower Camp using Mullaperiyar water, the charge was 12 per kiloWatt per hour. Tamil Nadu uses the water and the land, and the Tamil Nadu government has been paying to the Kerala government for the past 50 years 2.5 lakhs as tax per year for the whole land and 7.5 lakhs per year as surcharge for the total amount of electricity generated. The validity of this agreement is under dispute between the States of Kerala and Tamil Nadu. As of 2013 the matter is pending before a Division Bench of the Supreme Court. The dispute puts into question the power of the federal government of India to make valid orders respecting Indian States, in this case regarding a watershed and dam within one state that is used exclusively in another.

Construction

In May 1887, construction of the dam began. As per "The Military Engineer in India" Vol II by Sandes, the dam was constructed from limestone and "surkhi" at a cost of 104 lakhs, was 173 feet high and 1241 feet in length along the top and enclosed more than 15 thousand million cubic feet of water. Another source states that the dam was constructed of concrete and gives a figure of 152 feet height of the full water level of the reservoir, with impounding capacity of 10.56 thousand million cubic feet along with a total estimated cost of 84.71 lak.
The construction involved the use of troops from the 1st and 4th battalions of the Madras Pioneers as well as Portuguese carpenters from Cochin who were employed in the construction of the coffer-dams and other structures. The greatest challenge was the diversion of the river so that lower portions of the great dam could be built. The temporary embankments and coffer-dams used to restrain the river waters were regularly swept away by floods and rains. Due to the coffer dam failures, the British stopped funding the project. Officer Pennycuick raised funds by selling his wife's jewelry to continue the work. In Madurai, Pennycuick's statue has been installed at the state PWD office and his photographs are found adorning walls in peoples homes and shops. In 2002, his great grandson was honoured in Madurai, a function that was attended by thousands of people.
The dam created a reservoir in a remote gorge of the Periyar river situated 3,000 feet above the sea in dense and malarial jungle, and from the northerly arm of this manmade waterbody, the water flowed first through a deep cutting for about a mile and then through a tunnel, 5704 feet in length and later through another cutting on the other side of the watershed and into a natural ravine and so onto the Vaigai River which has been partly built up for a length of 86 miles, finally discharging 2000 cusecs of water for the arid rain shadow regions of present-day Theni, Dindigul District, Madurai District, Sivaganga District and Ramanathapuram districts of Tamil Nadu, then under British rule as part of Madras Province.
The Periyar project, as it was then known, was widely considered well into the 20th century as "one of the most extraordinary feats of engineering ever performed by man". A large amount of manual labour was involved and worker mortality from malaria was high. It was claimed that had it not been for "the medicinal effects of the native spirit called arrack, the dam might never have been finished". 483 people died of diseases during the construction of this dam and were buried on-site in a cemetery just north of the dam.
In 2012, it was announced that a memorial dedicated to dam engineer Pennycuick would be erected at the dam site.

Protected area

The Periyar National Park in Thekkady, a Protected area of Kerala, is located around the dam's reservoir, the Periyar lake. 62 different kinds of mammals have been recorded in Periyar, including many threatened ones. Periyar is a highly protected tiger reserve and hosts 35 tigers above two-years of age as of January 2017 in the reserve. Declared an elephant reserve on 2 April 2002, the population of Indian elephants in 2005 was estimated at 1100, however Periyar suffers greatly from poaching of elephant being the worst affected of South Indian sanctuaries.
Other mammals found here include gaur, bison, sambar, barking deer, mouse deer, dholes, mongoose, foxes and leopards. Four species of primates are found at Periyar – the rare lion-tailed macaque, the Nilgiri langur, the common langur, and the bonnet macaque. According to a report by the Kerala Forest Research Institute, the protected area surrounding the dam and reservoir is classified as a biodiversity hot spot.

Dam safety

After the 1979 Morvi Dam failure which killed up to 15,000 people, safety concerns of the aging Mullaperiyar dam's and alleged leaks and cracks in the structure were raised by the Kerala Government. A study conducted by The Centre for Earth Science Studies, Thiruvananthapuram, had reported that the structure would not withstand an earthquake above magnitude 6 on the Richter scale. The dam was also inspected by the Chairman, CWC. On the orders of the CWC, the Tamil Nadu government lowered the storage level from 152 feet to 142.2 feet then to 136 feet, conducted safety repairs and strengthened the dam.
Strengthening measures adopted by Tamil Nadu PWD from 1979 onwards include cable anchoring of the dam's structure and RCC backing for the front slope. During a recent scanning of the Mullaperiyar dam using a remotely operated vehicle by the Central Soil and Materials Research Station on directions from the Empowered Committee of the Supreme Court, the Kerala Government observer opined that "mistakes in the strengthening works carried out by Tamil Nadu" in 1979 damaged the masonry of the dam.
Current safety concerns relate to several issues. Since the dam was constructed using stone rubble 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. Moreover, the dam is situated in a seismically active zone. An earthquake measuring 4.5 on the Richter scale occurred on 7 June 1988 with maximum damage in Nedumkandam and Kallar. Subsequently, several tremors have occurred in the area in recent times. These could be reservoir-induced seismicity, requiring further studies according to experts. A 2009 report by IIT Roorkee stated that the dam "was likely to face damage if an earthquake of the magnitude of 6.5 on the Richter scale struck its vicinity when the water level is at 136 feet".

Justice A.S. Anand Committee (The Empowered Committee)

On 18 February 2010, the Supreme Court decided to constitute a five-member empowered committee to study all the issues of Mullaperiyar Dam 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. The five-member committee will be headed by former Chief Justice of India A. S. Anand to go into all issues relating to the dam's safety and the storage level. 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.
The then late Tamil Nadu Chief Minister M. Karunanidhi said that immediately after the Supreme Court announced its decision to set up a committee, he had written to Congress president asking the Centre to mediate between Kerala and Tamil Nadu on Mullaperiyar issue. However, the then Leader of Opposition i.e., the late Chief Minister of Tamil Nadu J. Jayalalithaa objected to the TN Government move. She said that this would give advantage to Kerala in the issue. Meanwhile, Kerala Water Resources Minister N. K. Premachandran told the state Assembly that the State should have the right of construction, ownership, operation and maintenance of the new dam, while giving water to Tamil Nadu on the basis of a clear cut agreement. He also informed the media that former Supreme Court Judge K. T. Thomas will represent Kerala on the expert panel constituted by Supreme Court.
On 8 March 2010, Tamil Nadu told the Supreme Court that it was not interested in adjudicating the dispute with Kerala before the special "empowered" committee appointed by the apex court for settling the inter-State issue. However, Supreme Court refused to accept Tamil Nadu's request to scrap the decision to form the empowered committee. The Supreme Court also criticized the Union Government on its reluctance in funding the empowered committee.
Setting at rest the controversy over the safety of the 116-year-old Mullaperiyar dam, the Empowered Committee, headed by the former Chief Justice of India A.S. Anand, has said it is "structurally and hydrologically safe, and Tamil Nadu can raise the water level from 136 to 142 feet after carrying out certain repairs."
In its report submitted to the Supreme Court on 25 April 2012, the committee is understood to have said: "The dam is seismically safe." Last year's earth tremors in that region "did not have any impact on the Mullaperiyar dam and the Idukki reservoir and there was no danger to the safety of the two dams."
In regard to the dam safety issue of Mullaperiyar between the states of Kerala and Tamil Nadu, Hon’ble Supreme court in its order dated 7 May 2014 constituted a 3-member Supervisory Committee under Chairmanship of CWC Officer in the rank of Jt. Secretary to the Centre, The Additional Chief Secretary, WRD, Govt of Kerala and Principal Secretary, PWD, Govt of Tamil Nadu are the members of the Committee.
It was decided to constitute a Supervisory Sub Committee to scrutinize all data for close monitoring of the safety of the dam in 2nd Supervisory committee meeting. The Supervisory Sub-Committee brings to the notice of the supervisory committee urgent issues, if any. The Supervisory Sub-Committee is headed by CWC Officer in the rank of Deputy Director. The members of the Sub-Committee are from both the member states
Incumbency of Chairman, Supervisory Sub Committee on Mullaperiyar Dam:
Present: M. S. Saravana Kumar, Dy. Director
Past: 1. Harish Grish Umbarje,Dy. Director
2. D. Ashokan, Dy. Director

Interstate dispute

The control and safety of the dam and the validity and fairness of the lease agreement have been points of dispute between Kerala and Tamil Nadu states.
Supreme court judgment came on 27 February 2006, allowing Tamil Nadu to raise the level of the dam to after strengthening it. Responding to it, Mullaperiyaru dam was declared an 'endangered' scheduled dam by the Kerala Government under the disputed Kerala Irrigation and Water Conservation Act, 2006.
For Tamil Nadu, the Mullaperiyar dam and the diverted Periyaru waters act as a lifeline for Theni, Madurai, Sivaganga and Ramnad districts, providing water for irrigation and drinking, and also for generation of power in Lower Periyaru Power Station. Tamil Nadu has insisted on exercising the unfettered colonial rights to control the dam and its waters, based on the 1886 lease agreement.
Kerala has pointed out the unfairness in the 1886 lease agreement and has challenged its validity. However, safety concerns posed by the 119-year-old dam to the safety of the people of Kerala in the event of a dam collapse, have been the focus of disputes from 2009 onwards. Kerala's proposal for decommissioning the dam and constructing a new one has been challenged by Tamil Nadu.
Tamil Nadu argues that building a new dam is for gaining unfair tax revenues from developing states, which is a qua within India, to the detriment of the revenue producing states, i.e., a form of wealth distribution. It is a microcosm of the bigger problem that India faces with China, which is building dams on Brahmaputra.
Tamil Nadu has insisted on raising the water level in the dam to 142 feet, pointing out crop failures. However, the court has clarified Tamil Nadu is not a riparian state. 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."
The Kerala Government maintains that this is not true. During the year 1979–80 the gross area cultivated in Periyar command area was. After the lowering of the level to, the gross irrigated area increased and in 1994–95 it reached. The Tamil Nadu government had increased its withdrawal from the reservoir, with additional facilities to cater to the increased demand from newly irrigated areas.
In 2006, the Supreme Court of India by its decision by a three-member division bench, allowed for the storage level to be raised to pending completion of the proposed strengthening measures, provision of other additional vents and implementation of other suggestions.
However, the Kerala Government promulgated a new "Dam Safety Act" against increasing the storage level of the dam, which has been challenged by Tamil Nadu on various grounds. The Supreme Court issued notice to Kerala to respond, however did not stay the operation of the Act even as an interim measure. The Court then advised the States to settle the matter amicably, and adjourned hearing in order to enable them to do so. The Supreme Court of India termed the act as not unconstitutional. Meanwhile, the Supreme Court constituted a Constitution bench to hear the case considering its wide ramifications.
The Kerala Government states that it does not object to giving water to Tamil Nadu as a shared commodity, their main cause of objection being the dam's safety as it is 116 years old. Increasing the level would add more pressure to be handled by the already leaking dam. They also raised the problematic definition of inter-State river when in its entirety the river goes into the sea within Kerala without passing through any other states. They also raised the complexity of the judgment and disputes that it can raise in other states that have small catchments of other-State rivers and right to claim part of waters.
In a 2000 Frontline edition, one author stated thus:
"For every argument raised by Tamil Nadu in support of its claims, there is counter-argument in Kerala that appears equally plausible. Yet, each time the controversy gets embroiled in extraneous issues, two things stand out: One is Kerala's refusal to acknowledge the genuine need of the farmers in the otherwise drought-prone regions of Tamil Nadu for the waters of the Mullaperiyar; the other is Tamil Nadu's refusal to see that it cannot rely on or continue to expect more and more from the resources of another State to satisfy its own requirements to the detriment of the other State. A solution perhaps lies in acknowledging the two truths, but neither government can afford the political repercussions of such a confession".
Tamil Nadu wants the 2006 order of Supreme court be implemented so as to increase the water level to.
In May 2014, Supreme Court of India declared Kerala Irrigation and Water Conservation Act, 2006 as unconstitutional. The Supreme Court on Wednesday struck down the law passed by the Kerala Assembly on the Mullaperiyar Dam that said that the water level cannot be increased beyond 136 feet. The court has ruled that Tamil Nadu can increase the water level to 142 feet and constituted a permanent Supervisory Committee consisting of three members one member from the Central Water Commission of The Water Resource Ministry who will act as the chairman of the Supervisory Committee and two other members from the respective states. The Supervisory will also have a Sub Committee under it.
The powers and functions of the Supervisory Committee shall be as follows:
The Committee shall supervise the restoration of FRL in the Mullaperiyar dam to the elevation of 142 ft.
The Committee shall inspect the dam periodically, more particularly immediately before the monsoon and after the monsoon and keep close watch on its safety and recommend measures which are necessary. Such measures shall be carried out by Tamil Nadu.
The Committee shall be free to take appropriate steps and issue necessary directions to the two States Tamil Nadu and Kerala or any of them if so required for the safety of the Mullaperiyar dam in an emergent situation. Such direction shall be obeyed by all concerned.
The Committee shall permit Tamil Nadu to carry out further precautionary measures that may become necessary upon its periodic inspection of the dam in accordance with the guidelines of the Central Water Commission and Dam Safety Organisation.
On 20 February 2015 Kerala Government Withdraws a plea seeking clarification on 5 May 2014 Judgement which the apex court had allowed the raising the water storage level of the dam to 142 feet and go before the three-member Mullaperiyar committee. The apex court had also rejected the plea for giving open court hearing and said there was no reason to interfere with the judgement of its five-judge Constitution Bench.
In an application, the Tamil Nadu government said Kerala has defied the Supreme Court's judgments in "letter and spirit". Without mincing words, it accused the Kerala government of harassment by denying Tamil Nadu officials free entry to carry out routine periodical maintenance and repairs of the dam. The application wants the Supreme Court to direct Kerala government to allow free access to Tamil Nadu officials to the dam and its appurtenant structures to collect data and change the weekly chart in the Mullakodi rainfall station. It said the court should direct Kerala to allow Tamil Nadu to transport the machinery and materials required for carrying out repairs.

Proposal to construct a new dam

Kerala enacted the Kerala Irrigation and Water Conservation Act, 2006 to ensure safety of all 'endangered' dams in the State, listed in the second schedule to the Act. Section 62A of the Act provides for listing in the schedule, "details of the dams which are endangered on account of their age, degeneration, degradation, structural or other impediments as are specified". The second schedule to the Act lists Mullaperiyar constructed in 1895 and fixes 136 feet as its maximum water level. The Act empowers Kerala Dam Safety Authority to oversee safety of dams in the State and sec 62 empowers the Authority to direct the custodian "to suspend the functioning of any dam, to decommission any dam or restrict the functioning of any dam if public safety or threat to human life or property, so require". The Authority can conduct periodical inspection of any dam listed in the schedule.
In pursuance of Kerala's dam safety law declaring Mullaiperiyar dam as an endangered dam, in September 2009, the Ministry of Environment and Forests of Government of India granted environmental clearance to Kerala for conducting survey for new dam downstream. Tamil Nadu approached Supreme Court for a stay order against the clearance; however, the plea was rejected. Consequently, the survey was started in October 2009.
On 9 September 2009 Govt. of Tamil Nadu stated that there is no need for construction of a new dam by the Kerala Government, as the existing dam after it is strengthened might function like a new dam.
In May 2014, the Supreme Court of India ruled that the water level in the dam could be increased to 136 ft. It also struck down an 2006 amendment included in the Kerala Irrigation Water Conservation Act 2003 that deemed certain fixed water level for old dams.