Timely intervention by dam safety officials has helped avert a massive outflow of water from the Idukki reservoir, and a subsequent crisis in power generation, on Saturday night. Police personnel on duty noticed a huge teakwood floating towards the open shutter of the Cheruthoni dam around 10 p.m. They immediately informed Kerala State Electricity Board (KSEB) officials, who alerted the District Collector. The shutter was closed in 15 minutes.
A dam safety official said if the stump was trapped in the open shutter, it would have been difficult to reach the site on boat due to the sheer force of the outflow through the open gate. The shutter could have been damaged too. “A damaged shutter cannot be closed. If the wood was trapped at the gate, a similar problem would arise,” he said.
The five shutters of the Cheruthoni dam release water from a height of 2,373 ft. The tree trunk was noticed when the water level was at 2,400 ft. If the shutter was blocked, water would have to be released from the reservoir till the level reached 2,373 ft. The trunk’s movement to the shutter was soon blocked and it was later removed. Since the water inflow declined, the closed shutter did not open again.
The official said tree trunks had been similarly removed three or four times earlier too. Trees on the reservoir banks get uprooted and fall in. However, this time, it occurred at night. It could be spotted and removed as the dam area was lit. He pointed out that if such a huge quantity of water was released, the State would have faced a power crisis during summer. Idukki reservoir, one of the largest in Asia, is reserved mainly for power generation during the summer season when the demand escalates.
At Peringalkuthu in 2018
In smaller reservoirs, if such blockades occur when a shutter remains open, water is drawn out to clear them. In the floods of August 2018, when huge trees and debris got deposited in the Peringalkuthu dam, they were removed after drying out the reservoir. It was a costly affair and required days to complete.