In the wake of Kerala government raking up Mullaperiyar dam issue again following unprecedented rains, a water expert and farming community have urged the State government to immediately commence the survey for drilling a new tunnel on the Western Ghats to enhance water drawing capacity towards Tamil Nadu side.
“It is high time, Tamil Nadu government started the survey as per May 2014 judgement of the Supreme Court on the dam dispute,” said former Public Works Department Executive Engineer S. Suthanthira Amalaraj.
The five-member Constitution Bench of the Apex Court directed Tamil Nadu to conduct surveys and feasibility studies for the proposal of having a new tunnel within a year from the delivery of judgement. “As per the court order the survey and feasibility study should have been completed by middle of 2015. But, it seems Tamil Nadu Government is yet start it,” he said.
When asked about the new tunnel proposed by the Supreme Court, Deputy Chief Minister O. Panneerselvam, on Monday, said that he was not aware of such a judgement. “I am hearing about this only from you (now),” Mr. Panneerselvam, a two-time Chief Minister, who also held the portfolio of PWD when the final verdict was delivered, said.
Mr. Amalraj said the issue of new tunnel gained importance in the backdrop of Kerala again asking TN to lower the water level from the maximum permissible level of 142 feet to 139 feet.
“This is only because of fear perception over safety of the dam. The Constitution Bench had clearly stated that the dam was safe to hold water at 142 feet,” Mr. Amalraj, who has worked in Periyar dam, said. The overflow from Periyar dam towards Idukki district in Kerala has now triggered it.
Tamil Nadu could not prevent the overflow into Kerala, as it was handicapped in drawing of water through the tunnel. “The maximum drawal from the dam through the tunnel is 2,300 cusecs. If this quantum is further increased with an additional tunnel, Tamil Nadu can evacuate more water during monsoons,” he added. It would also mitigate the “unfounded” fear of Kerala.
Even when the inflow in the Periyar dam was as high as 25,000 cusecs in recent days, the discharge through the head sluice at 101.10 feet through the tunnel was possible only up to 2,300 cusecs. This led to fast increase in storage level.
“Additional tunnel is not a new issue. Even Col. John Pennycuick, who built the dam, wanted to have another tunnel at 130 feet. But, that was not possible as the Madras Presidency then could not afford funds for the second tunnel,” said A. Tirupathi Vasagan , secretary, 18 Canal Farmers’ Association, Theni. At least now the State government should commence the survey, he said.
