Though there is a lull in rainfall, heavy inflow through the Periyar and tributaries continues
Despite the increased power generation at the Moolamattom powerhouse, the water level in the Idukki reservoir was nearing the orange alert level on Thursday.
The water level at 4 p.m. was 2,392.82 ft. As per the new rule curve fixed by the Central Water Commission, the orange alert level is 2,396.85 ft and the red alert level 2,397.85 ft. The dam has to be opened once the water level reaches 2,398.85 ft.
An official at the Dam Monitoring and Research Station at Vazhathoppe said the water level was high now compared to the water level during the same period in the past two years. In 2018, when the dam was opened in the August floods, the water level on October 15 was 2,387 ft and last year it was 2,376.3 ft.
The official said the water level was higher last year compared to the previous year because the dam was not opened. However, it was rare that water level increased to this level by the middle of October, as per the data available with the Kerala State Electricity Board. The catchment area recorded a rainfall of 29 mm on Thursday.
Though there was a lull in rainfall on Thursday, there was heavy inflow through the Periyar and other tributaries resulting in nearly one ft rise in the water level in the past 24 hours. Since power generation had been increased, the water level was being monitored every three hours and changes made to generation levels.
A senior official at the dam safety wing said an unpredictable weather condition was prevailing now. Though the rainfall was much lower on Thursday, there was prediction of a depression over the Bay of Bengal.
He said the water level continued to increase as a result of the heavy rainfall in the past two days. The inflow was three times higher than the powerhouse discharge. The opening of the dam shutters depended on rainfall, inflow, and the situation downstream.
If the rain gained momentum and inflow became heavy in the coming days, the shutters could be opened prior to the level for water release fixed as per the new rule curve level, he added.