Tamil Nadu’s failure to control release of water from the Mullaperiyar dam till the reservoir reached its full capacity is one of the reasons for the flash floods in Kerala that killed over 350 people and damaged property worth thousands of crores, the Kerala government said in the Supreme Court on Thursday.
In its affidavit, Kerala blamed the sudden release of water from the dam for the unprecedented floods. “The sudden releases from the Mullaperiyar Dam, 3rd largest reservoir in the Periyar Basin, forced us (Kerala) to release more water from the Idukki reservoir, downstream of Mullaperiyar, which is one of the causes of this deluge,” read the affidavit, filed by the chief secretary of the state, Tom Jose.
Located in the upper reaches of the Western Ghats above the Idukki reservoir, Mullaperiyar dam is being operated by the Tamil Nadu government even though it is wholly situated in Kerala. The catchment area of the Idukki reservoir is 650 sq km and the Mullaperiyar reservoir has a catchment area of 624 sq km.
The state, the affidavit stated, was managing the spate of water by controlling spill and letting a major portion of the flood waters escape to the sea by “implementing a strict operational control over the spill of the two largest reservoir systems of Idukki and Idamalayar in synchronization with eight small other reservoir systems in the Periyar basin.”
Kerala’s affidavit comes in response to a direction by the top court on August 17. The order came on a petition filed by residents of Kerala to maintain structural safety of the dam, which as per an earlier SC judgement is being overlooked by the three-member supervisory committee that was constituted on the directions of the top court in 2014.
On August 17, the Centre informed the top court that the National Crisis Management Committee (NCMC) dealing with devastating floods in Kerala has decided to reduce water level in Mullaperiyar dam to check additional inflow to avert further disaster.
According to Kerala, the secretary, water resources, Government of Kerala, had addressed a letter to her counterpart in Tamil Nadu as well as the chairman of the supervisory committee on the Mullaperiyar dam urging the commencement of controlled releases of water.
The request was made to get sufficient time to evacuate people so that they would not be hit by flash floods in their sleep. But no positive assurance was received from Tamil Nadu even after repeated requests.
The Mullaperiyar reservoir water was suddenly discharged by opening all thirteen shutters to Idukki downstream at midnight on August 15. Discharge continued and around 9,000 cusecs of water was let out between 8 am and 1 pm and 21,450 cusecs at 2pm. The district administration was at that time frantically evacuating people from the downstream of Idukki dam.
With a view to avoid such disasters in future, Kerala has urged the top court to form a management committee that would directly report to the supervisory committee, appointed at the behest of the Supreme Court, to manage day-to-day operations of Mullaperiyar dam.
The deluge faced by Kerala was unprecedented in its recent history and it has already surpassed the devastation caused by the 1924 floods, the affidavit said. “
It was now considered the most intense flood to have hit Kerala in the last 100 years as 13 of the 14 districts were affected and 774 of the total 1564 villages were inundated.
Of its population of 3.48 crore, more than 54 lakh people i.e. one-sixth of the state’s total population was directly affected by the deluge,” read the affidavit filed by the Kerala government.>