Kurnool: With concerns over the safety of Srisailam dam rising, the demand to make public the National Institute of Oceanography (NIO) underwater video report is growing louder. There is apprehension over the safety of the dam in the event of a flood as was seen in 2019.
The immediate cause of worry for experts and retired engineers who worked at the dam, is a ditch that has formed at the plunge pool of the Srisailam dam.
It is being said that the NIO had submitted a report after studying the 186-feet deep ditch that formed on the river bed.
Former Union minister Kotla Jaya Surya Prakash Reddy expressed concern over the safety of Srisailam dam foundation and has urged the government to share the NIO report.
“Our dams are built to last 100 years”, said Mr A.B. Pandya, former chairman of the Central Water Commission, who is heading a panel to study structural soundness of the dam. Srisailam dam chief engineer C. Narayana Reddy said that the Pandya panel was scheduled to visit the dam in November to assess the situation.
The Srisailam dam in AP and Nagarjunasagar dam in Telangana state are examples of neglect.
Increasing the spillway capacity to handle sudden release of large volumes of water from the dams are essential to prevent erosion of the plunge pool, the area where water from the spillway lands, and ensure safety of the mammoth structure.
Mr Narayana Reddy told this newspaper that the dam safety committee, which inspected the dam, had advised the state governments to conduct a survey.
He said there was no threat to the dam structure at present. It can withstand inflows of up to 1,00,000 cusecs of water. He said there was no threat of getting floods of the kind seen in 2009. He said the department was monitoring the situation with great care.
Several scientific studies, dating as far back as 1979, had pointed out that the bedrock at the dam site was associated with many joints, layers of soft shale soil, weak pockets and fractured zones as well as cavities.
Though a concrete apron was constructed to prevent erosion, studies showed that it needed repairs and regular upkeep to prevent erosion of the bedrock under the plunge pool and the spillway.
