With passions reaching fever pitch between Kerala and Tamil Nadu over the decommissioning of the century-old Mullaperiyar dam, experts are asking whether dams do collapse in India?
Three dams have collapsed in Andhra Pradesh in the last five years. These include the Subbaraya Sagar in East Godavari in 2010, the Palamvagu Dam in Khammam in August 2008 and the Gundlavagu Dam in Warangal district in 2006.
Prof. T. Shivaji Rao, director, Centre for Environment Studies at the Institute of Science, Visakhapatnam, highlighted that these dams collapsed due to poor construction and improper design.
“In all, 50 dams built post-independence have failed, including the Kodaganar dam in Tamil Nadu, Nanaksagar dam in Punjab and the Machhu 11 dam in Gujarat and the Koyna dam in Maharashtra,” Prof. Rao stated.
A confidential report prepared by the Delhi-based Centre for Soil and Materials Research Station revealed that investigations submitted to the Empowered Committee (EC) of the Supreme Court had highlighted that the masonry cover of the Mullaperiyar dam had been severely damaged between the depth of 32m and 29m throughout the length of the dam.
The Detailed Project Report submitted to the EC by the Kerala state government also raises major safety issues.
Mullaperiyar dam, constructed 116 years ago is 365.7 metres long and 53.6 metres high, is presently one of the oldest dam’s in the world.
While its walls are covered with rubble masonry, its core is built with hydraulic lime and surkhi comprising a mixture of crushed bricks, sand and sugar.
Members of the Central Water Commission (CWC) have recommended lowering the maximum water level in the reservoir. A CWC member pointed out, “The dam should last for another 10 years or so. But no dam can survive for 999 years which is the length of the lease between the two states. A new dam will have to be constructed and this is the best time to start work on a new dam.”