Mettur Sub-Divisional Officer R Kovalan has issued the flood alert to 12 districts downstream the reservoir stating that due to heavy inflow, the water level might reach the maximum of 120 feet soon and excessive water would be let out in the Cauvery.
The alert sent by e-mail asked district officials to take steps to move people living on the banks of Cauvery to safer areas, they said.
PWD officials said if the current level of inflow continued, the water level will reach the maximum of 120 feet in two days, in which case the shutters of 16 vent surplus weirs will be lifted allowing the excess water to flow out.
As per practice, the first flood alert is issued when the water level reaches 110 feet, the second once the level crosses 115 feet and the final warning would be given once the reservoir attains its full level, they said.
As of this morning, the dam was getting an inflow of 89,723 cusecs with the storage increasing to 76.576 tmc ft against the capacity of 93.4 tmc ft.
The water level in the dam has been incrementing at a faster pace in the last few days with Karnataka stepping up discharge from its dams across Cauvery in view of copious inflows following heavy rains in catchment areas.
This has prompted the Tamil Nadu Government to advance the opening of the dam for irrigation in Cauvery delta districts from August 15 to today. Initially, 9,000 cusecs would be released from this evening and it would be gradually stepped up.
The opening of the dam would also help in generating hydro power up to a maximum of 440 MW through the hydel stations, officials said.