Lights resembling the tricolour were flashed over the cascading waters of the dam on Wednesday night.
With water flowing to the Periyar River from Mullaperiyar Dam, houses located in areas such as Manchumala, Aattoram, Kadassikadavu and Karuppupalam were flooded
He asked everyone to remain cautious as the water inflow to the dams and reservoirs is still strong due to rains in the eastern part of Kerala.
A low-pressure formation over the North Western Bay of Bengal, off the coast of Odisha and Bengal, is likely to intensify in the next 24 hours, warns IMD.
Idukki dam loses water worth Rs 21 lakh every hour with opening of 3 shutters.
The gushing water will reach Kavalangad in Ernakulam district in 1 hour and 10 minutes. The water is estimated to reach Kaladi in 4 hours, Aluva in 9 hours and Varappuzha in 12 hours.
He said the distributaries and streams from the Periyar river have been cleaned under 'Operation Vahini' to ensure the natural flow of water.
The water level in 10 of KSEB's bigger dams, including the largest Idukki dam, has not crossed even the 'blue level', the first stage when a warning is issued.
Tamil Nadu is now attempting to raise the water level in the dam to the permitted capacity of 142 ft as it has reached 135.9 ft already.
According to reports, a new low-pressure area is likely to form in the Andaman Sea in the Bay of Bengal in the next 12 hours.