New Delhi: While hearing petitions filed on issues pertaining to the 126-year-old Mullaperiyar dam, the Supreme Court on Wednesday said that the first question to be addressed is the quantity of water the reservoir can withstand.
The apex court, while hearing pleas about the safety of the dam built in 1895 on the Periyar river in Idukki district of Kerala, said that rule curve may be the most crucial issue.
“Frankly, we are not here deciding about the distribution of water. That is very clear. The only issue is about safety of dam. The first question to be addressed is this dam can withstand what quantity of water. That quantity is defined in the form of rule curve,” news agency PTI quoted the bench, also comprising Justices AS Oka and CT Ravikumar as saying.
The counsel, appearing for Kerala, told the bench headed by Justice A M Khanwilkar that the process for setting up a new dam in the downstream reaches of the existing dam should start and the upper rule level of Mullaperiyar dam should be 140 feet instead of 142 feet.
Senior advocate Jaideep Gupta, appearing for Kerala, told the bench that the issue is not about sharing of water but the safety of the dam.
The bench said the state has broadly raised four points, height of the water level, release of water, modernisation of instrumentation and regular supervision and maintenance of the dam.
There are one or two other issues and Kerala has suggested that a supervisory panel should be re-constituted and its functions should be expanded, Gupta said, adding that they have suggested both Kerala and Tamil Nadu should have their technical members in the committee.
He said the other long standing issue as far as Kerala is concerned is that the process for setting up a new dam has to begin.
“It is our submission that the correct remedy in the long term is construction of a new dam, just downstream..,” Gupta said, adding, “once the dam is ready, the existing dam can be discontinued and the new dam will take over.”
He further said, “Instrumentation is the only way to track the safety of a dam,” adding, “as I said, the dispute is not relating to sharing of water. It is relating to dam safety. Kerala is before your lordships saying that the dam is not safe as it stands. Safety depends upon the height of the water in the reservoir.”
He also said that the peak water level should be 140 feet as at the peak of monsoon, the level goes beyond 142.
The bench observed that this issue of upper level has been considered by the SC earlier. “If it is decided, unless there is change in circumstances, why it needs to be changed,” the bench asked.
“140 feet is the correct level. Two feet cushion has to be kept,” Gupta said, adding that climate change problem is very critical and from 2017, the rainfall pattern in the area has changed.
“Now this aspect has to be taken into consideration in deciding whether everything that was decided in the past is to remain or we should look at something,” he added as quoted by PTI.
Notably, the Kerala government had earlier told the apex court that "no amount of rejuvenation" can perpetuate the dam and there is a limit to the number of years a dam can be kept in service through maintenance and strengthening measures.
It had also said the only permanent solution for removing the "eternal threat owing to the safety concerns" of the dam and for protecting the safety of the people living in the downstream of Mullaperiyar dam is to build a new dam in the downstream reaches.
In an affidavit filed before the Supreme Court, the Kerala government had urged that the proposal to fix the upper rule level of Mullaperiyar dam at 142 feet on September 20 as formulated by Tamil Nadu may be avoided.
In its response, Tamil Nadu had earlier said that “repeated assertion” of Kerala and petitioners from there in the pleas seek to decommission the existing dam and construction of a new dam, which is “wholly impermissible” in the light of the apex court verdict on its safety.
"The dam has been found to be hydrologically, structurally, and seismically safe,” Tamil Nadu had said.
The next hearing on the matter is scheduled to take place on Thursday.