With water level of the Mettur Dam touching the full reservoir level of 120 feet on Sunday night, the authorities in charge of the dam began releasing 85,000 cusecs (cubic feet per second). Gradually, the outflow would be stepped up to over one lakh cusecs.

This was as per the plan of the Water Resources Department (WRD) of the Public Works Department (PWD) to let out the entire inflow once the dam touched the FRL. In 2005 too, just as being done now, surplus water was released through 16 shutters of the dam. The previous occasion when the dam touched the FRL was in December 2010.

After the dam touched the FRL at 9 p.m., the release was increased to 85,000 cusecs from 75,000 cusecs. Earlier in the day, the authorities issued flood alert to people living along the banks of the Cauvery river in several districts.

A senior official in Chennai adds that the discharge from Karnataka reservoirs across the Cauvery continues to be of the order of 1,35,000 cusecs. On Saturday, the release was around 24,600 cusecs.

Also, with the increase in discharge, the power generation by the Mettur hydel power station also reached the maximum of 250 MW on Sunday morning. Meanwhile, officials from revenue and the police department in the Salem district were closely monitoring the situation and people were issued warning through beating of drums in interior villages and people living along the water catchment area to move to safer place. The Water Resources Department of the Public Works Department also plans to divert water through the Coleroon from the Upper Anicut, located on the outskirts of Tiruchi city. The flood alert has been issued to areas which are situated along the Coleroon.

When water is diverted through the Coleroon, the Veeranam tank in Cuddalore district, which has become one of the major sources of water for Chennai, will be filled up. Water to the tank can be conveyed through the 22-km-long Vadavar Channel, which branches off from the Lower Anicut. At present, the tank is empty. Apart from meeting the requirements of Chennai, the tank has an established ayacut of 48,000 acres to serve.

The official says that after filling up the Veeranam tank, the authorities will have no option other than to let the surplus water into the sea. Asked whether water can be diverted to the Pudukottai district, which was reported to have witnessed public agitations over lack of water supply, from the upcoming barrage at Mayanur, the official replies it is not possible now as the work has not yet been completed. But, parts of Pudukottai can be covered by water release through the Grand Anicut Canal, which is expected later this week.

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