Landslides heap sand and mud deposits in dams, affect power production

Last fortnight’s rains have caused widespread damage to life and property. Even the many power stations of the Tamil Nadu Electricity Board (TNEB) in Nilgiris have not been spared. The rains caused huge landslides which have, in turn, caused heavy sedimentation of mud in the power stations. In some places, the sediment covers almost 60 per cent of the station’s areas, forcing the TNEB to take up repair works on a war footing.

The heavy rains, which began on August 2, continued for a week. Avalanche recorded 2,978mm of rains from August 7 to 9, one of the heaviest for this season. Around 7,200 acres of forest in Avalanche saw landslides in several areas. Nearly ten streams in the area were flooded and brought in waters mixed with stones, uprooted vegetation and trees to the dams.

This has left behind a lot of sediments in the dams of Avalanche, Emerald and Kundah. The sedimentation has blocked giant water pipes connecting Upper Bhavani to Avalanche, Kundah, Ketti, Barali and Pillur TNEB stations, bringing power production to a standstill.

Among these, Avalanche resumed power production though the waterways were clogged with mud and soil. But power production was stopped to take up repair work which have continued on a war footing for the past two weeks. These TNEB stations have a capacity to generate 455 megawatts of electricity, but due to clogging and sediment deposits, only 200 megawatts are being generated.

The TNEB crew surveyed Kulukundah and Pykara station’s Upper Bhavani, Avalanche, Emerald, Kundah, Ketti and nearly 13 other dams and some 30 check dams. If power production is resumed without clearing the sand and mud deposits, power producing equipments could be damaged. Plans are afoot to remove the sediments in the fastest way possible before resuming full production.

The supervising engineer of Kundah power facility R Ravi said, “The recent heavy rains have caused swollen streams and tributaries of many rivers to bring stones, uprooted vegetation and soil deposits to the dams which caused water-logging and soil sedimentation. We are checking each of these dams and will submit a report to the TNEB headquarters and then take quick steps to clear the logged dams.”