The story behind the construction of the Dam:
John Pennycuick works in the British Army in India. One day, when he was going through the geographical map of the above area, he saw a big river at the top of the hill (2890 feet above sea level).
The river (called as Periyar River) was going waste through mountains and finally ended in the sea. He thought "If ever we could divert the river in the opposite direction, millions of people will be benefited. He worked out the logic like this: " If we stopped the flow of river by building a dam, then , water level of the river will increase and it will automatically flow through the opposite direction.See the images of river before and after the construction of the Dam.
But, he observed one more hinderence; a small mountain. He has to make a hole of 6000 feet through this mountain. He submitted his proposal for construction of dam as well as making hole to the British Government.(Note : the same idea was there for the Captain-cum-engineer Caldwell in 1808 but he dropped this idea thinking tunneling is not feasible. Before Caldwell, in 1778, Ramnad Raja also thought of diverting the water by constructing a dam. But, because of financial constraints, he could not proceed further )
See the images below which show the view of the River before and after the construction of Dam.
|Mullaiperiyar river before construction of dam|
|Mullaiperiyar river after construction of dam|
British govt refused to allot any more fund for this work. As John Pennycuick is also a member in Madras Legislative Council he was more attached to the people of that State. When the govt refused fund, he went back to England and sold all his properties and using that money he completed the dam in December 1895. Now 2.17 lakh acres (68,000 hectares) of land is benefited by this dam.
FATE OF THIS MULLAIPERIYAR DAM and the RIVER:
The Dam is situated in the place of Kerela State while the River is in Tamilnadu State. See the above image of the dam again. If you increase the water level more, tamilnadu will get benefit by getting more water. If water level is permitted to lower down, then kerela will get benefit by releasing more water through the dam. Hence, this water-level problem went to court. Court ordered(in 2006) a water level of 142 feet. Kerela govt allows the level of 136 feet on dam safety grounds
Technical Details of the Periyar Dam:
1. This type of Dams are called as Gravity Dams.
2. Gravity Dam means, these dams are stable mainly because of Force of Gravity.
3. Height of periyar dam is 176 feet.
4. Length of the dam is 1200 feet.
5.Thickness at the base is 138 feet.
6.Thickness at the top is 12 feet
7. Materials used for construction of Dam: (sugar+calcium oxide=mortar),limestone.
8. The construction of this dam is regarded as "ONE OF THE MOST EXTRAORDINARY FEAT OF ENGINEERING EVER PERFORMED BY MAN"
Profile of John Pennycuick
1. Date of Birth: 15 Jan 1841
2. Pennycuick trained in Addiscombe Military College
3. Pennycuick Joined in Royal Engineers in 1858
4. Pennycuick came to India in 1860
5. He worked as Cheif Engineer in indian PWD from 1890 to 1896.
6. He was appointed as a member of Madras Legislative Council in 1893
7. Pennycuick is also a faculty member of Madras University
8. His hobby is playing cricket.
9. He constructed the Mullai periyar dam (earlier called as Periyar Dam)
10. The dam reesrvoir is called as Periyar-thekkady Reservoir.
|Mullai periyar dam as seen in google maps|
|john pennycuick who constructed mullai-periyar dam|
|Close up look of Mullai periyar dam which has now become a dispute between two states|
CLICK ON THE IMAGE TO ENLARGE
| Mullai periyar dam|
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|Mullai periyar dam during construction in 1887|
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|Mullai periyar dam in 1895|
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|Mullai periyar another view|
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|image of idukki dam in kerala. This dam is called as Arch Dam. The capacity of this dam is more than 4 times that of Mullaiperiyar Dam.CLICK ON THE IMAGE TO ENLARGE|
|A video made by the tamilnadu PWD engineers|
on mulllaiperiyar dam conflict.
What is the stand of Tamilnadu Government (as on December 2011)
The Mullai Periyar Dam is a gravity dam built in 1886- 1895 with stone masonry and lime surkhi concrete. Gravity dams use their weight to resist the water pressure and other external forces like wave pressure, earthquake forces etc. for the reservoir to remain stable. The Periyar Lease deed between the Maharaja of Travancore and Madras Presidency with effect from 1.1.1886 for a period of 999 years was executed on 29.10.1886 for diversion of waters to the Madras Presidency under “Periyar Project”. An extent of about 8,000 acres has been given on lease on payment of an annual rent of Rs.51- per acre. The waters of the dam irrigate about 2.23 lakh acres in Theni, Dindigul, Madurai, Sivagangai and Ramanathapuram Districts of Tamil Nadu. On 29.5.1970, two supplemental agreements were entered into between Kerala and Tamil Nadu; one for increasing the annual lease rent from Rs.51- to Rs.301- per acre and subjecting it to revision every 30 years; and in turn surrendering the fishing rights to Kerala and the other permitting Tamil Nadu to generate Hydro electric power on payment of certain charges to Kerala according to the quantum of power generated. These were executed as successors in interest to the Principal Deed of 1886.
There are examples in various parts of the world of masonry dams which have been strengthened. The Roosevelt Dam, in Arizona, USA, was built in 1911. In 1980, modifications were designed to meet safety standards and flood control. Its capacity had also been expanded. The Joux Dam built in France in 1905 was heightened in 1952 by top concrete section and post tension anchors. Upper Glendevol is a gravity dam in U.K. and was provided with rock-fill buttress downstream.
The strengthening works carried out in the case of the Mullaiperiyar Dam from 1980 to 1994 on the recommendations of the Chairman of the Central Water Commission are almost similar. In the old dam,the front and back of the dam were constructed as stone masonry with lime surkhi mortar. The centre of the dam was filled with lime surkhi concrete. Gravity dams withstand the pressure of water and tremors using their weight. As a short term action, to increase the weight of the dam, 21 feet wide, 3 feet thick RCC capping structure was provided on top of the dam for its entire length. Due to this, the weight of the dam is increased by about 35 tons per metre, ie. a total of 12000 tons weight has been added to the structure. As a part of medium term action, cable anchoring was also done on the basis of pre-stressing technology. At a distance of 5 feet away from the front face of the dam, on the top of the dam, four inch diameter holes were drilled at 9 feet internally along the length of the dam up to a depth of 30 feet inside the foundation rock. Inside these holes, 34 numbers of 7 mm diameter high strength steel wires were inserted. These cables were anchored in the foundation rocks. Initially concrete was poured to a depth of 20 feet and then cables were inserted and anchored. From the top a prestressing force of 120 tons was applied and locked. At this stage, concrete mix was poured again to fill the hole and then it was closed at the top. Due to this, these prestressed cables hold the dam strongly with foundation rocks with a force of 120 tons. 95 such cables were inserted and concrete filled at an interval of 9 feet for the entire length of the dam and strengthened to withstand various forces including seismic forces. As a long term measure, a 32 feet wide RCC backing concrete with 10 feet deep foundation up to a height of 145 feet above the ground abutting the cap structure was erected on the back of the dam. The existing dam and the backing concrete were designed and joined together using state-of-the art technology to behave as a single dam structure. Based on the Central Water Commission’s recommendation, while building the backing concrete, two drainage galleries were also built at levels of 10 feet and 45 feet in the new structure. With these, water seepage from the dam is being measured daily.
It has been proved and established scientifically that a certain amount of water must leak as seepage from the dam, if it needs to be safe, strong and healthy.
In fact, when the water level rises above (FRL) 152 feet, to safeguard the dam, excess water is discharged by a spill way with 10 vents, each measuring 36×16 ft, which was already there. Using this, 86,000 Cu.ft of water/second can be discharged. Moreover, based on the advice of the Central Water Commission, an extra spilling capacity of 36,000 cu.ft. / second was added by constructing 3 vents measuring 40×16 ft. So, the current spilling capacity of the dam is approximately 1,22,000 cu. ft/second.
Thus, it is amply clear that the dam is safe and adequate steps have been taken by Tamil Nadu to ensure its safety.
On 27-2-2006, the Hon’ble Supreme Court of India by its judgement permitted Tamil Nadu to raise the water level in the Mullai Periyar Dam initially to 142 feet and carry out the remaining strengthening works. After the strengthening works are completed to the satisfaction of the Central Water Commission, independent experts will examine the safety angle, before the water level is permitted to be raised to 152 feet. To thwart this, “The Kerala Irrigation and Water Conservation (Amendment) Act 2006″ was passed by the Kerala Legislative Assembly and the amended Act came into force from 1 8.3.2006. The maximum water level of the Mullaiperiyar Dam was fixed at 136 feet by this Act. The Suit filed by the Government of Tamil Nadu challenging the Constitutional validity of this Amendment is still pending in the Supreme Court.
In October, 2009, in the Supreme Court, while hearing Tamil Nadu’s petition, a Bench comprising Justices D.K.Jain, Mukundakam Sharma and R.M.Lodha observed “if every State in inter-state disputes sought enacting a legislation not to give effect to ourjudgement, it would have serious consequences. When this Court said that Tamil Nadu can raise the water level up to 142 feet, can you (Kerala) nullify it by enacting a legislation and fixing the water level at 136 feet?” it asked Senior Counsel Rajiv Dhawan appearing for the State of Kerala. “What is the sanctity of the Supreme Court if its judgements are not implemented?” The Kerala Counsel said the State had to come up with the legislation as it was concerned with the safety of its people. At this, Justice D.K.Jain said:”This Court is equally concerned with the safety of the people. The Court had taken all the facts and concerns expressed by the two parties before passing the decree”.
To Kerala’s objections to the Central Water Commission’s studies, the Court remarked “the Central Water Commission is a statutory body. Do not label it with tar”. Following this, a Five-Member Constitution Bench was constituted in November, 2009.
In February, 2010, the Constitution Bench comprising Justices D.K.Jain, B.Sudershan Reddy, Mukundakam Sharma, R.M.Lodha and Deepak Verma remarked “Your arguments are unfounded, misleading, fallacious and jugglery of words. You should support it with evidence.” The Court made these remarks as it was not impressed with Kerala’s argument that if the water level of the dam was allowed to be raised beyond 136 feet, it would lead to its collapse endangering public safety as it would submerge several villages. The Bench had said the arguments cannot be accepted as even during the three floods witnessed in 1924, 1943, and 1961, the water level had reached a maximum of 153.90 feet, 154.80 feet and 152.0 feet respectively, as against the designed maximum water level of 155 feet.
On February 18, 2010, the Hon’ble Supreme Court appointed an Empowered Committee to look into various aspects excepting legal and constitutional aspects including the validity of the Amendment, 2006, under the former Chief Justice of India, Dr. A.S. Anand as its Chairman. Tamil Nadu and Kerala appointed two former Supreme Court Judges from their respective States.
The Empowered Committee is expected to submit its report to the Hon’ble Supreme Court by February, 2012. The Committee has used and is using the services of the Central Water Commission, Central Water and Power Research Station, Geological Survey of India, Bhabha Atomic Research Centre and Central Soil and Material Research Station for the different studies and tests, conducted at the dam site and in their laboratories.
The human settlements in the area are much above the reach of the flood waters of the Mullaiperiyar Dam and the ldukki Reservoir of Kerala is designed to absorb the flood and to moderate flood up to about 4,00,000 cubic feet of water per second. In this respect, the Hon’ble Supreme Court has observed in its order dated 27th February 2006 that ” it is the case of the State of Kerala that despite the ‘copious rain’, the Idukki Reservoir is not filled to its capacity. While the capacity of the reservoir is 70.5 tmc., it was filled only to the extent of 57.365 tmc. This also shows that assuming the worst happens more than 11 tmc water would be taken by Idukki Dam”. When the waters reach ldukki Dam, which is about 50 Kms away, it will have only a velocity of 3 feet per second. It is also reported that when the water level at Mullaiperiyar Dam is 136 feet, the water spread area is 4678 acres and that if the water is stored to 155 feet, the water spread area will be 8591 acres. Since water has not been stored above 136 feet for a long time, the water spread area has been encroached upon by land grabbers in Kerala who have built resorts and other buildings on the lands leased to Tamil Nadu. If the water level is increased from 136 feet, these resorts will get submerged in water. This is also cited by some as the possible reason for the plea to decommission the Mullaiperiyar Dam.
There is no valid reason to believe that the Mullai Periyar Dam is unsafe. It is unfortunate that a fear psychosis among the people of Kerala is being built up. As the Mullai Periyar Dam is fully safe and as good as new, the people of Kerala should see through the machinations of vested interests and should feel secure that the retrofitted Mullai Periyar Dam is as good as new and therefore not a threat to the lives and properties of the people of the region.