The Stanley reservoir in Mettur started receiving heavy inflow since Saturday morning following the combined discharge of more than 19,000 cusecs from Kabini and Krishnarajasagar reservoirs in Karnataka on Thursday.
The dam first recorded 15,000 cusecs at 8 a.m., which later increased to 16,129 cusecs at 4 p.m.
Water level stood at 81.470 feet with live storage of 43.438 tmcft. Discharge for Delta irrigation, including drinking water needs of wayside habitations, was 12,009 cusecs.
Water being released from the dam since July 28 reached Mukkombu on Saturday morning and was expected to reach Kallanai later in the evening.
The administration in downstream areas has warned people in riverside habitations to move to safer places since Karnataka reservoirs were expected to release more than 40,000 cusecs from Saturday night since they had been registering steep increase in inflow following an intense south-west monsoon.
Salem, Dharmapuri and Namakkal administrations have banned coracle rides across the river.