A flood alert was on Wednesday issued to people living along the banks of Periyar river in Theni district after the Mullaiperiyar dam's level came close to the maximum level.
The level on Wednesday morning touched 134.8 ft, against the maximum of 136 ft. A similar alert was issued in Kerala's Idukki district, official sources said.
With the inflow into the dam at 3379 cusecs, the level is likely to touch 135 ft on Wednesday evening. A second flood alert was likely to be issued by that time, they said.
The discharge from the dam was 1929 cusecs, they said. Two turbines of Mullaiperiyar hydro-electric power station continued to remain idle and water could not be drawn through them, the sources said.
The dam produced only 48 MW of power, against its full capacity of 96 MW.