Competitive Exams: Current Affairs 2012: Mullaperiyar Dam

  • In recent years, the controversy over the Mullaperiyar dam has acquired new dimensions. A purely technical matter has turned into an emotional and political issue between Kerala and Tamil Nadu.

  • For the best decision, the Mullaperiyar issue needs to be considered from all technical and engineering aspects. It is surprising, therefore, that the silting of the reservoir has not been taken into consideration by any party.

  • The process of sedimentation reduces the life of a reservoir. The estimated life of any reservoir is of the order of 120 to 180 years (broadly speaking, not more than couple of centuries).

  • As per available records, the storing capacity of Mullaperiyar Dam has been lost by about 50 per cent during the last 116 years. The rate of silting in peninsular India is less compared to the alluvial rivers of Himalayan region. It may take another 150 to 200 years for the Mullaperiyar dam to get fully silted up:

  • Even if the request of one party to increase the water level is partially or fully granted, it cannot be a final or permanent solution. With the addition of silt every rainy season, the volume of water in the dam would continue to reduce and the demand to raise the water level would crop up again.

  • The cumulative accumulation of silt in the reservoir is not dangerous to the stability of the dam as it does not exert any dynamic pressure on the body of the dam. The only danger of silt deposition is effective reduction in the storage capacity of the reservoir.

  • In the case of Mullaperiyar dam de-silting is not even possible due to its design, type of construction, age of the dam and the building material.

Courtesy: The Hindu