[BREAKING] Mullaperiyar dam "extremely vulnerable"; should be decommissioned, new dam constructed: Kerala to Supreme Court

In a significant development, the Kerala government has told the Supreme Court that the Mullaperiyar dam is extremely vulnerable due to its age and large catchment area and should be decommissioned and a new dam should be built (Dr. Joe Joseph v. State of Tamil Nadu)..In a note submitted before the top court, the Pinarayi Vijayan led CPI(M) government said that the Mullaperiyar dam is a 126-year-old structure constructed from lime-surkhi concrete at a time when seismic forces were not considered in its design and is extremely vulnerable despite strengthening measures having been carried out twice. Adding to the vulnerability is the fact that the dam has a large catchment area but only limited storage capacity, the noted said."The catchment area of Mullaperiyar reservoir is 624 sq.km. The gross storage capacity is only 12.758 TMCft at 142 ft. Mullaperiyar therefore is exceptionally vulnerable because it has a large catchment area and limited storage capacity," the note said.Hence, any failure of the dam could be catastrophic and beyond human imagination, the State said."The consequences of any failure of this dam could be extremely catastrophic and beyond human imagination. The apprehensions of the Govt. of Kerala regarding the life and safety of more than 30 lakh people of 5 districts residing downstream of the dam has to be given due importance and consideration," the written note said.Hence, the logical next step is construction of a new dam to ensure water to Tamil Nadu and security to people living downstream and to decommission the existing dam, the note said. .Logical next step is construction of a new dam to ensure water to Tamil Nadu and security to people living downstream and to decommission the existing dam.State of Kerala .The submissions came in a plea by the Kerala government to ensure that water level in the dam's reservoir is not allowed to exceed 139 feet, three feet below the permissible limit of 142 feet prescribed by the 2014 judgment of the top court.The Supreme Court had in 2018 passed an order to maintain water level at 139 feet during the Kerala floods as a temporary arrangement.The Kerala government in its present plea has asked for a similar prayer in view of the incessant rains in the State which has led to a rise in water level in the reservoir.When the matter was heard on October 25, Monday, the Court had observed that the issue surrounding fixing of maximum water level in is a serious one but it is not something which the Court can decide upon, since it lacks the expertise for the same.A Bench of Justices AM Khanwilkar and CT Ravikumar, had therefore, said that it is the task of the expert supervisory committee appointed by the Court to decide the same and asked the committee to take a call expeditiously after discussing with all parties concerned.Pursuant to that, the expert committee had met and suggested that no change in water level is required and water level can be allowed to reach the 142 feet limit fixed by the Supreme Court in 2014.The Kerala government had, however, dissented and has filed the present note setting out its concerns.In the note, the Kerala government submitted that there would be an exponential increase in the water pressure and uplift pressure acting on the dam when the water level is raised from 136 ft to 142 ft.Since, the catchment area of the dam is big and the capacity is less, water level in the Mullaperiyar reservoir increases rapidly compared to Idukki dam downstream which has catchment area of 650 sq.km and has a capacity of 70.5 TMC ft."Idukki reservoir is nearing full reservoir level (FRL) and any sudden large releases from upstream can worsen the situation, forcing to make large releases from Idukki Dam affecting the downstream. Presently Idukki dam is in yellow alert," the note said.Taking into all the factors, the dam should be decommissioned and new dam should be built, the Kerala government said..The Tamil Nadu government has, however, maintained that the dam is safe and water level should be allowed upto 142 feet as prescribed by Supreme Court in 2014."Continuous campaign is going on in Kerala. All their concerns are misplaced," Tamil Nadu's lawyer Shekhar Naphade had told the Supreme Court yesterday. The matter will be taken up for further hearing today at 2 pm.