Thiruvananthapuram: With the water level in the Idukki reservoir touching 2,395 feet tonight, just nine feet short of the full level, an orange alert was issued by the authorities.
The Kerala State Disaster Management Authority (KSDMA) said an orange alert does not mean that shutter operations would be done anytime now.
The shutters would be opened only in daylight and after sufficient notice is given to the public and all stakeholders concerned, it said in a statement.
There was no need for the public to panic, KSDMA said.
The final red alert would be issued when the water level touches 2,399 feet, it said.
The full level of the dam is 2,404 feet. The water level is related to the Mean Sea Level and catchment area.
Earlier, the Kerala government put the Army, Navy, Air Force and Coast Guard on alert to meet any eventuality in case water is released.
KSDMA had said the water level touched 2,394.72 feet at one PM and an alert would be issued when the level reaches 2395 feet.
Kerala State Electricity Board sources said that when the level reaches 2,397 feet, there was a possibility of water being released on a trial basis for one or two hours.
This was to find out if there were any obstruction and diversion on the route the water flows, they said.
A team of National Disaster Response Force has already been deployed in Ernakulam and Thrissur and another team would reach Idukki, Kerala Chief Minister Pinarayi Vijayan said in a Facebook post.
The reservoir comprises three dams -Idukki, Cheruthoni and Kulamavu, built for the the Idukki Hydroelectric Project.
"Army, navy, airforce and coast guard have been asked to be on vigil. Two helicopters have been kept ready. There is no need to panic as of now. The State Disaster Management Authority will give timely directive in this regard," he said.
"Coast Guard is also ready with small boats to evacuate people if water enters low-lying areas of Ernakulam," he said.
People living downstream of the reservoir upto Lower Periyar area in Ernakulam district have been asked to be vigilant, he said.
In the event of opening the sluice gates of Cheruthoni dam, the water would flow through Ernakulam from Idukki, before reaching the Arabian sea, Vijayan said.
According to KSDMA, restrictions have been imposed on tourists visiting some areas near the dam.
The Idukki reservoir's shutters were last opened in 1992.
This is the first time it would attain full-level during the South West Monsoon period.
While Idukki dam is used to store water, the other two dams are meant to route water to the powerhouse.