Tuesday, January 3, 2012


Over to the experts

OFFICIALS and other interested parties associated with the Mullaperiyar dam in Tamil Nadu are in favour of maintaining the status quo regarding the 116-year-old dam.
According to C. Suthanthira Amalraj, retired executive engineer, Tamil Nadu Public Works Department, the design of the Mullaperiyar dam made it impossible to lower its water level below 136 feet. “It is not technically possible to lower the water level since there is no sluice in the dam to open the floodgates to drain the water, unlike in other dams. The storage can be drawn only through the tunnel to the Tamil Nadu side and it too has much limitation…. Lowering it to 120 feet is as good as not having the dam at all,” he said ( The Hindu, December 2, 2011). Amalraj explained that traditional reservoirs were constructed across rivers with sluices to regulate water flow downstream. He noted: “The sluices are constructed at the river bed level or slightly above the bed. But the Periyar dam is simply a wall-like structure [without any sluices] meant to block the west-flowing river and make the water stagnant so that it can be diverted to the eastern side through the tunnel.”
The 13 spillways were built at a height of 136 ft and so water flowing above that alone could be drained. The horseshoe-shaped tunnel is located at a height of 104 ft. The maximum discharge through the tunnel varies from 1,800 cusecs to 2,000 cusecs. “The rate of discharge is dependent on the head pressure created by the level of water. So it is technically impossible to contain the water level at 120 ft unless there is no inflow into the dam,” Amalraj said.
R.V.S. Vijayakumar, retired chief engineer, Tamil Nadu PWD, said the dead storage level in the dam is 104 ft. “If Kerala were to build a new dam 50 feet below, the dead storage level will be 154 feet. So how can Kerala give us water?” he asked. The Empowered Committee has set up several committees and they have checked the subsoil, rocks below it, and so on. They have studied the dam's structure, foundation and core. “Kerala is making all this ruckus to pressure the Empowered Committee,” Vijayakumar said.
A Tamil Nadu PWD official asserted, “There is no scientific proof that the dam is not safe.”
M. Puthisigamani, president of the Periyar-Vaigai Water Users' Association, said: “The dam is quite strong. There is no need to demolish it and build a new one.”
T.S. Subramanian

Heightened tensions
in Thiruvananthapuram
Kerala and Tamil Nadu lock horns once again over the 116-year-old Mullaperiyar dam.
SUBMERGE the polemics, legal tangles and conflicting technical claims, and the participants in the inter-State dispute over the Mullaperiyar dam – one of the oldest and highest ‘solid masonry gravity dams' in the world – will no longer be able to ignore the anxiety and panic that the 116-year-old structure has created among the people in Idukki, especially, and four other districts in Kerala.
The spontaneous initial outpouring of the people was followed by unusual protests demanding the decommissioning of the dam in the wake of intense rain and repeated low-intensity tremors in Idukki district, at locations over 30 kilometres away from Mullaperiyar, on November 18 and 26.
Following seasonal rains in the catchment areas of the dam, the reservoir was fast filling up when the first of the quakes occurred, and the spillway level of 136 feet (41.45 metres) was crossed within a few days.
The dam filled to capacity and the series of “minor” earthquakes activated an unprecedented unity of purpose in Kerala. Ever since the detection of fresh leaks on the dam's surface in 1979, people have demanded that the water level in the reservoir be lowered and a new dam be built.
The protests have taken the form of silent marches, hunger strikes, hartals and ‘human walls' in the five districts through which the Periyar flows, and other State-wide campaigns, some involving violence. The State government, on its part, demanded immediate mediatory and legal remedies from the Centre and the Supreme Court.
Mullaperiyar is the first in a series of hydroelectric and irrigation projects across Kerala's longest river, the Periyar, which originates in the Western Ghats and drains into the Arabian Sea and the backwaters near Kochi. Tamil Nadu, across the Western Ghats, is the sole beneficiary of the British-built dam and it is against any further reduction in the water level in the reservoir. Instead, it wants the level to be raised to 142.40 ft (43.4 m), as an interim measure, and further to 152 ft (46.32 m), as per the recommendations of a committee of the Central Water Commission (CWC) that examined the dam nearly two decades ago and suggested several measures to strengthen it.
By constructing the dam in the deep jungles of the Western Ghats, about 2,800 ft (853 m) above sea level, the British rulers of the then Madras Presidency had, from 1895, diverted the West-flowing Periyar river across the Ghats to the east, through a 5,704-feet (1,738.5 m) tunnel that opened into a tributary of the Vaigai river in the then Madurai district. This remarkable engineering feat achieved with the hard labour of mostly Indian workers today sustains irrigation and drinking water supply in five districts of southern Tamil Nadu. (The Periyar is also known as the Mullaperiyar, after a tributary, the Mullayar, joins it about 50 km from its origin in the Sivagiri Hill, east of Peerumedu.)
Though the dam is located in Kerala, it is controlled, managed and operated by Tamil Nadu, under a lease agreement of 1886 between the British and the erstwhile Travancore State, and validated subsequently by Kerala and Tamil Nadu in 1970.
The original agreement gave the British the right over “all the waters” of the Mullaperiyar and its catchment for diversion to the British territory (now Tamil Nadu) for 999 years. The waters of a river with about 5,284 square kilometres (out of a total of 5,398 sq km) of its catchment area in Kerala, stored in a reservoir within Kerala territory, thus came to be used exclusively by the people of southern Tamil Nadu from 1895 onwards, when the diversion project was inaugurated. According to one estimate, over 70 lakh people in Tamil Nadu's Theni, Dindigul, Madurai, Sivaganga and Ramanathapuram districts today depend on the waters of the Mullaperiyar reservoir (the scenic Thekkady lake) for the irrigation of about 2.5 lakh acres (1 acre = 0.4 hectare) and for drinking water needs. The (upper) Periyar has thus transformed a once-drought-prone region in the southern part of Tamil Nadu into breathtaking green valleys, vineyards and rich fields growing paddy, banana, coconut and a variety of vegetables and fruit. Since 1970, Tamil Nadu has been using the water to generate 140 megawatt (MW) of electricity as well.
In 1979, Tamil Nadu was forced to reduce the water level in the reservoir after detection of leaks in the dam. However, its requirement of the Periyar waters for irrigation had only been increasing year after year. The total irrigated area in the Periyar-Vaigai basin has expanded substantially, leading to a quantum jump in the water required from the reservoir. Farmers' groups in Tamil Nadu area have demanded that the Mullaperiyar water level be raised and “new channels” be opened from the Periyar system for irrigating new areas.
During most of the Periyar project's early history, the section of Kerala falling on the downstream areas of the reservoir seemed to have remained generally a water-surplus region, with plenty of rain (and meagre population in the Ghat areas). But from the late 1970s, soon after Kerala constructed the Idukki hydroelectric project 50 km downstream of the Mullaperiyar dam and denudation and encroachment of the surrounding areas increased, the State too began to feel the pinch. But it could not use (particularly during summer) even a wee drop from the huge source of water within its own territory.
For most part of the year, no water flowed from the Mullaperiyar reservoir to Kerala even as the population in the valleys between the Idukki and Mullaperiyar dams too began to increase. Almost all the water that reached the Idukki reservoir for most part of the year was only from the catchment areas downstream and from the Periyar's tributaries.
Safety concerns
The detection of leaks in the Mullaperiyar dam in 1979 had led to concerns about the dam's safety even though the reservoir level was brought down to 136 ft. Minor earthquakes were regularly reported in the region, and by the 1990s, Kerala government representatives, in private conversations, began expressing bitterness at the insensitivity of Tamil Nadu to the security concerns in Kerala. “Whether any State can rely permanently on the resources of another State” was a question that began to be raised, but at no time was there a demand that the Periyar waters be denied to Tamil Nadu.
A senior adviser to the State government on Inter-State River Water Disputes put it succinctly to Frontline in October 1998, when the dispute had reached a new low: “The case of the Mullaperiyar dam is peculiar in that the beneficiary is comfortably situated elsewhere and the donor stands to face the peril if something happens. Some experts have said the dam is safe. But can any government afford to throw caution to the winds?
Understandably, such arguments were brushed aside by Tamil Nadu as a ploy to deny it the full use of its legal entitlement of “all the waters” flowing “into, through, over or from” the Mullaperiyar dam and about 8,000 acres around it, as the Periyar Lease Deed of 1886 had ordained.
On the other hand, in Kerala concerns about the safety of the dam were sounding increasingly genuine because of frequent reports about the condition of the aging dam and its increasing vulnerability in the context of earthquakes and changing weather patterns (see separate story).
Different approaches
Until the question of the dam's strength became an important issue, a significant facet of the dispute was the dramatically different approaches of the two States at the practical level. For the most part, in the first three decades after Independence, the people of Kerala were by and large aware of the Mullaperiyar reservoir (also known as the Thekkady lake) as a tourist spot and the dam as such, or its long history or its value as a key water source for the neighbouring State, evoked little interest.
It was rarely that Mullaperiyar was discussed in Kerala, and successive governments, political leaders and officials who dealt with it did so in a “complacent”, “lethargic” and, according to later allegations, “insincere” fashion.
In Tamil Nadu, the genuine needs of the farming communities and other beneficiaries of the Periyar project in the southern parts ensured that the State government and political leaders (a number of them representing regional interests) did their homework in all their discussions with Kerala about the agreement, the dam or quantum or use of the waters of the Periyar.
The difference in the attitudes of the governments and political leaderships of Kerala and Tamil Nadu is most evident in the way the two sides handled the issue of renewing the Periyar Lease Deed of 1886.
All agreements made by the British and the princely states had lapsed with the passing of the Indian Independence Act of 1947. To suggestions that the agreement should be rewritten, Kerala neither showed interest in a review nor did it seem concerned about future water needs. Water continued to flow into Tamil Nadu from the Mullaperiyar dam even in the absence of an agreement.
In fact, through an informal agreement in 1954, Kerala allowed Tamil Nadu to generate electricity, too, from the Periyar waters, following a proposal to construct the Vaigai reservoir (near Madurai) to store the waters of the Periyar and the Vaigai rivers during the non-irrigation periods. The informal power generation agreement – a result of Central intervention and personal contacts among statesmen-leaders of the two States – was formalised in May 1970 with retrospective effect from November 1954.

Controversially, Kerala also entered into an agreement with Tamil Nadu to renew the 1886 lease deed. This it did without any public discussion on the issue of Tamil Nadu once again being given the legal right over “all the waters” from Mullaperiyar for its exclusive use and without an assessment of possible future requirement of the Periyar waters for its own use.
In fact, very few changes were made to the original agreement. Tamil Nadu was to pay a revised rent of Rs.30 an acre a year, instead of a lumpsum of Rs.40,000 a year; the rent was to be revised every 30 years; and Tamil Nadu surrendered to Kerala fishing rights in the lake and the surrounding areas. “Tamil Nadu got all that it wanted, and Kerala was perhaps bothered only about getting some additional compensation,” a senior Kerala government official said.
Barely a decade later, following the detection of leaks in the dam, which was 84 years old, a CWC team, led by its Chairman K.C. Thomas, conducted a study of the dam. A member of the team told Frontline that the committee “found no danger to the dam”, but had “as a matter of abundant precaution” recommended the lowering of the reservoir water level to 136 ft (from 142.40 ft at that time) until measures to strengthen the dam were completed in three stages. (The team had also recommended that the water level could be raised in stages to the full reservoir level of 152 ft.)
Since 1998, Tamil Nadu has claimed that it has carried out all the important strengthening measures suggested by the CWC team and has demanded that the water level be raised to 142 ft. Kerala, in turn, has argued that the reinforcements made the dam safe only at the reduced water level of 136 ft. From this point onwards, Kerala officials increasingly began talking about the possibility of the breaching of the dam in the event of a major flood, and it was only a matter of time before the issue reached the courts.
Strangely, the two States were fighting over the raising of the water level even though only on a few occasions the reservoir level had actually risen to 136 ft or more and water had flowed out into Kerala through the 13 shutters (three of them newly built) of the spillway. Kerala government officials also claimed that 95 per cent of the water reaching the reservoir was already being used by Tamil Nadu and, therefore, its fight was only over the 5 per cent or so that spilled over to Kerala occasionally during the monsoon season.
Interestingly, in the 12 years that followed, while Tamil Nadu remained focussed on its singular demand that the water level must be raised, its claim that the dam was “as good as new” (after it was reinforced) appeared increasingly specious to the people of Kerala. Frequent earthquakes in nearby areas and reports about fissures and seepage of water through the dam, and leaching out of lime from its core on a sustained basis over the years had led to a genuine fear among the people living in the downstream areas of Kerala.
Over to Supreme Court
By 1999, the dispute reached the Supreme Court. The court ruled initially that it should be solved through negotiations and mediation by the Central government (the National Democratic Alliance led by the Bharatiya Janata Party was in power then). A joint technical committee, which was set up despite Kerala's objections about political bias favouring Tamil Nadu in the appointment of its members, ruled that the water level could be raised initially to 142 ft.
On February 27, 2006, the Supreme Court decided the issue in favour of Tamil Nadu. It ordered, on the basis of the committee's report, that the water level be raised to 142 ft and that the baby dam be strengthened to raise the level eventually to 152 ft. The decision came as a surprise in Kerala, where concern about the dam's safety was becoming a live issue. There were allegations about the possible connivance of some of the State's politicians and officials with Tamil Nadu in the court cases.
On March 15, 2006, for the first time in the Mullaperiyar project saga, Kerala's politicians displayed unusual unity in enacting the Kerala Irrigation and Water Conservation (Amendment) Act, 2006 – a law passed with particular focus on the safety of “endangered dams” in the State.
In brief, “notwithstanding any other law, treaty, agreement or direction of courts”, the Act prevents “any agency” from increasing a reservoir's water level or expanding its capacity without the permission of a special Dam Safety Authority constituted under it. The law also gave this Authority the power to inspect endangered dams, give instructions as to their safety, and decide the level of water that can safely be stored in them. The Authority could also decide on whether a dam needed to be demolished or decommissioned and direct the custodian (of a dam) to implement its directions.
Tamil Nadu appealed to the Supreme Court that the new law should be declared as unconstitutional in its application to the Mullaperiyar dispute, and that Kerala should be restrained from obstructing Tamil Nadu from raising the water level to 142 ft and from carrying out repairs to the baby dam (that would enable it to raise the level to 152 ft later on as per the order of the apex court).
The Supreme Court asked the two States to sort out the matter through negotiations or with the help of the Central government. By September 2006, Tamil Nadu went ahead with its preparations to raise the water level to 142 ft during the north-east monsoon season. But a 2.1 magnitude earthquake near the project area, with its epicentre in Tamil Nadu, raised a lot of concern among the people of Kerala, who were already protesting Tamil Nadu's move to increase the storage level at Mullaperiyar.
The scare in 2006
The rains in November 2006 only served to add to the scare in Kerala. On November 21, following a heavy downpour, the water level in the dam swelled to 139 ft (for the eleventh time in 27 years, after it was fixed at 136 ft by the CWC team). A high alert was sounded in Idukki district. Tamil Nadu's effort to channel the water resulted in the Theni-Kollam national highway being washed away at Irachippalam, and the Vaigai reservoir crossing its full level of 72 ft (21.9 m). That dam too was opened. Meanwhile, after an inspection of the baby dam, located on one side of the main structure at Mullaperiyar, the Inter-State Water Resources Department gave a report that spoke about its precarious condition.
Thus, a combination of scary (and continuing) natural events, focussed political strategies and legal measures finally helped Kerala focus on a counter-strategy that brought forth the question of safety of the 116-year-old gravity dam – built mainly with sandstone and lime-and-surkhi mixture at its core without an anti-seismic design and at a location close to an increasingly earthquake-prone zone.
Kerala's strategy
At an all-party meeting convened by the then Chief Minister V.S. Achuthanandan on November 20, 2006, Kerala took the decision that “a new dam and a new agreement” was the only solution to the vexed issue. At a subsequent inter-State meeting convened by the Centre in New Delhi, Kerala proposed that when a new dam is built, it will continue to give the same quantity of water from Mullaperiyar to Tamil Nadu. A decision to this effect was approved by the State Cabinet on August 14, 2007.
At about the same time, Kerala commissioned several studies, all of which expressed serious misgivings about the safety of the dam, even as Tamil Nadu continued to maintain that since the existing dam was as good as a new one after it was strengthened, the water level should in fact be raised to 142 ft. It also suggested that Kerala “may not raise the issue of a new dam any more”.
This was the context in which the Supreme Court, while considering Tamil Nadu's suit (for declaring the Kerala law as unconstitutional), ordered the two sides to maintain status quo with respect to the dam and, in November 2009, transferred the case to a Constitution Bench. In September 2009, the court had rejected a plea by Tamil Nadu for a stay order on the clearance granted to Kerala by the Ministry of Environment and Forests for conducting a survey for a new dam about 1,300 feet (396 m) below the present dam.
The Constitution Bench appointed a five-member Empowered Committee led by the former Chief Justice of India, Justice A.S. Anand, and including nominees of the two States, to study all issues relating to the Mullaperiyar dam, including its storage level and safety. The Empowered Committee is expected to submit its reports by February 2012, after an extension of its term. But the intense downpour and low-intensity tremors after mid-November has created an unprecedented situation of fear and disquiet in Kerala. The claim that over 35 lakh people in five districts would be in the path of a debris-ridden flood if the dam broke has gained currency. At the time of writing this, clashes had erupted in towns bordering the two States, there were attacks on shops and on vehicles plying across the border, and attempts by isolated groups to march into the Mullaperiyar dam site.
The State Cabinet decided to increase power generation in Idukki, Kerala's biggest hydroelectric project, in order to bring down the storage level in the reservoir and accommodate any calamitous flood from the Mullaperiyar, which everybody hoped would never come. In the Kerala High Court, where petitions had piled up questioning the State government's disaster preparedness or lack of it, statements made by the Advocate-General and technical experts on the impact of a possible dam-burst on Idukki and other dams below Mullaperiyar were widely analysed critically as a sign of the State's insincerity to its citizens.
Maybe, for the first time in its three-decade-long legal battle for raising the storage level at the Mullaperiyar dam, Tamil Nadu finds its legitimate (and so far dominant) claim over a lifeline water source that has served the people in five of its southern districts for over a century now being challenged by an equally valid argument – concern over the safety of the dam and the lives of thousands of people living in five districts in central Kerala.
“This is perhaps the only inter-State water dispute in which sharing of water is not an issue at all,” Chief Minister Oommen Chandy had said, while seeking an immediate lowering of the water level to 120 ft. He also reiterated Kerala's commitment to continue to provide “the same quantum of water” to Tamil Nadu as was being done now when a new dam was built.
But is that really not the issue, after all? Can any political leader or government in Tamil Nadu agree to give up the legal entitlement the State enjoys to “all the waters” flowing “into, through, over or from” the Mullaperiyar dam “and about 8,000 acres around it” on the basis of a 999-year lease agreement? Instead, on their own, will they be willing to brave the political repercussions of settling for a new dam and “the same quantum of water as the State is getting now”?
Significantly, over a decade earlier, at a conference of Chief Ministers of the two States on Mullaperiyar, held in Thiruvananthapuram at the behest of the Centre, one of Chandy's predecessors, E.K. Nayanar, had told his counterpart M. Karunanidhi: “It is an open question whether an agreement between an erstwhile princely state and the British government, which was palpably inequitable, and which binds down future generations without any concern for changing circumstances, and which appears to contain provisions that contravene existing enactments, should continue to be legally binding.”
Mullaperiyar today is a vexatious legal and political tangle, but given the fear factor in Kerala over a real-world ‘Dam 999', can any court, government or party take the huge risks involved in delaying the decommissioning of the old dam – unless they are so sure?

River   & Basin                                            : MullaiPeriyar River  &  Periyar Basin
Location                                                         : Lat 9o 03’ 20”   Long: 77o 08’ 45”
Construction Period                                      : 1887-1895
Cost                                                                 : 43.00 lakhs (18 crores for strengthening work)
Catchment area                                       : 232.60 sq.miles (602.4 sq.km)
Water spread area                                   :10.21 sq.miles (28.44 sq.km)
Design Flood                                            : 1.22 lakh cusescs (3454 cumecs)
FRL                                                          : 152’ (+2861’ {(or) +872.285 m}
MWL                                                        : 155’ {+2864’ (or) +873.20m}
Dead Storage Level                                  : 104’ {+2831‘ {(or) +857.65m}
Capacity of Reservoir at FRL                 : Gross 15,682mcft (444.06 mcum)
Vents                                                       : Old   : 10 Nos (36x16) or (10.97x4.88m)
Additional                                               :New : 2 Nos (40’x16’) or (12.19x4.88m)
Type                                                        :Old : Vertical Lift Shutter
                                                                : New: Radial Shutter
Crest Level                                             : 136’ (+2845ft) or 867.405m
Platform Top Level                                :177.65’ (+2886.75’) or 880.105m
Max.discharge                                       Old : 86,000 cusecs (2483.54 cumecs)
                                                               New: 36,000 cusecs(991.08 cumecs)


No comments:

Post a Comment