Kerala moves Ministry of Environment and Forests for new dam
The old dam is now having a water spread area of 3475.78 hectares
THIRUVANANTHAPURAM: The irrigation department has submitted a proposal to the Ministry of Environment and Forests seeking environment clearance for a new dam in Mullaperiyar.
The new dam, which is estimated to take an additional area of only 50 hectares, is sought to be constructed on the grounds that the existing dam is hydrologically and structurally unsafe and a threat to the lives of the people in six districts in the state. The twin goals of the new dam are to protect the lives of the people and to ensure continued supply of water to Tamil Nadu.
The new dam is proposed to be located 366m below the centre-line of the existing dam. The centre-line of the proposed alignment of the new dam is oriented at about 50 east of north. The proposed structure consists of a main dam and a saddle dam on the left flank.
The old dam is now having a water spread area of 3475.78 hectares. By constructing the new dam, the irrigation department’s proposal states, the additional area downstream of the old dam that will be submerged is only 25.66 hectares.
The total area required for the entire construction is only 50 hectares. The proposal states that the old structure has already outlived its “safe-life,” and that it has become unsafe to retain it further.
It states that periodic strengthening measures have not helped mainly because of the limitations of the process and materials adopted during a period when dam engineering was at its infancy. Besides describing the old dam as having outlived its useful life, the proposal states that the existing dam will not be able to withstand the impact of probable maximum flood and earthquake.
“The collapse of the old dam will trigger a cascading failure of the Idukki group of dams (Idukki, Cheruthoni and Kulamavu) resulting in an unimaginable degree of devastation in the thickly populated districts of Idukki and Ernakulam and also in parts of Kottayam, Thrissur, Pathanamthitta and Alappuzha districts,” the proposal states.