Today, a three judge bench of the Supreme Court headed by Justice Khanwilkar partly heard Sr. Adv. Jaideep Gupta appearing on behalf of the Respondent- State of Kerala concerning the Mullaperiyar Dam and the safety concerns of the structure.
Senior Counsel summarized the background of the matter while stating that the writ petition filed in the matter of Dr. Joe Joseph objects the constitution of a sub-committee by the Respondent 4- Supervisory Committee. Further, certain aspects such as the Rule Curve formulated by Tamil Nadu, Comprehensive Instrumentation Gate Operation Schedule have not been completed yet. The counsel informed that according to the substantive direction of this Court with regard to the above mentioned aspects, the CWC has already submitted a Report. There is one IA filed in this matter by Sachis Technology claiming that they have some technology which can be utilized for the purpose of Instrumentation, etc.
He further highlighted that the dispute in the matter is not related to sharing of waters, it is relating to dam safety. The stance of Kerala remains that the dam is not safe. One of the important factors on which safety depends is the height of water in the dam as increased volume of water will put pressure on the dam and if the water level keeps rising it has to be discharged from the reservoir. One method to do it is through discharging the water downstream by lifting the spillway gates which is not a recommended.
He explained the technical issues in simple words by stating that Rule Curve is a table of figures which shows the level of water in the reservoir that is to be maintained. In order to maintain this level the gates are to be open and shut, this is Gate Operation which has to be done in accordance with the schedule.
The court recorded that the four main issues which are common in the batch petitions are which regard to the Height of the Water level, Release of water and the modalities of that, Modernization of Instrumentation and Regular Supervision and maintenance of the dam.
The counsel submitted that state of Kerala has recommended reconstitution of the Supervisory committee as at present the committee consists of only one technical person who is the chairman of the committee. Therefore suggestion has been made to include two technical persons from both states as the Committee is basically doing technical job and even for the purpose of supervision there should be technical experts. Second, the functions of the committee should be enlarged a little bit.
The other long standing issue with respect to State of Kerala is to ascertain what is to be done in the long run. Therefore the stance taken by the state is that a new dam should be set up which would be down stream of the existing dam which would be the correct remedy in the long run as against the proposition of State of Tamil Nadu which is in favour of repairing the existing dam and raising the water height even further.
With regard to the issue of instrumentation the counsel submitted, “It is stated that it is imperative that a century old dam should have all necessary instruments for monitoring deformation, seepage/leakage quantity and quality, uplift pressure, pore water pressure, temperature, reservoir level and seismicity, as per the guidelines of Central Water Commission viz. Guidelines for the instrumentation of Large Dams (2018). There is no comprehensive instrumentation plan including seismic instrumentation for Mullaperiyar dam which is essential for monitoring the safety of large dam which is 126-year-old dam.”
The Counsel further denied the allegation that State of Kerala did not permit data collection from the Mullaikodi rain gauge station and submits that the access was merely regulated by the State. Contrary to the allegation they submit that under the state-of-the-art rainfall network an initiative by the State 11 Automatic Rain Gauges and 2 Automatic Weather Stations have been installed and raw data received from them has been shared with the State of Tamil Nadu. Furthermore, once the rectification of the instruments as well as the validation process is completed real time data can be shared with the State of Tamil Nadu.
The counsel submitted that there are serious gaps in Instrumentation on the part of State of Tamil Nadu which have to be addressed and further submitted that the instrumentation is inadequate and what is there is not functioning. “Therefore we do not know where this dam is going because instrumentation is the only way to ensure the safety of the dam.”
On the issue of RULE CURVE the counsel submitted that the maximum availability of water is at the end of the monsoon therefore that should be considered as the peak while registering the figures for determining the rule curve. Every dam in the same basin with similar rainfall pattern has a peak once a year or on 30th of November but in Mullaperiyar the CWC has accepted contention of Tamil Nadu that there can be 2 peaks. It peaks on 20th of September and again peaks on 30th November. This allows them to store more water without worrying about the fact that it is putting more pressure on the dam. This dam is being subjected to pressure twice a year. He strongly contended that Kerala is against having two peaks in a year. The second grievance of the state is that at its peak the water level should not be at 142ft as the dam in its present condition is not fit to hold water above 140ft which has been reinforced by the CWC report.
Furthermore, the rule curve is based on predictive calculations and therefore correct facts are essential for determination. The counsel proposed that Rainfall data varies across the Mullaperiyar basin which should be taken into account because if lower figure is considered then the prediction will turn out to be wrong.
Data taken into account regarding Probable Maximum Flood by CWC is different from the 2018 one. There have been several changes in the Climate of the region since 2014 and the rainfall pattern in the area has changed from 2017 onwards. Therefore all these factors should be considered and safety of the dam should not be compromised.
Jutice Khanwilkar pointed out that the main issue to be decided is regarding the maximum quantity of water that the dam can hold.
Counsel summarized his arguments on this issue by stating that even if the existing data is considered the water level goes above 142 ft for an unacceptable length of time. Moreover the existing data is incorrect and therefore if the correct data is considered it will go even above that. He proposed that even if the level suggested by Kerala is accepted all the demands of Tamil Nadu will be met.
Regarding the issue of Gate operation the counsel submitted that the sporadic spillway release at late night by the Tamil Nadu authorities has caused damage to the people and their properties living in the downstream of the dam in State of Kerala. This shows mismanagement of reservoir by Tamil Nadu officers disregarding the state of Kerala.
Therefore, Tamil Nadu should follow the principals of gate operation and the Gate operation should be decided after the decision of the Rule Curve issue.
Senior Counsel will continue his arguments tomorrow.
The Supreme Court three-judge bench of Justices AM Khanwilkar, Abhay S Oka and CT Ravikumar is seized of batch of pleas filed by Kerala, Tamil Nadu, activists and the residents living in the downstream of the Mullaperiyar dam raising the questions on the safety and maintenance of the 126-year-old structure, especially during heavy rains.