The first floodwaters of the Mahanadi were released from the Hirakud Dam at Burla in Sambalpur district on Thursday morning.
According to reports, the dam authorities, after performing traditional rituals, opened sluice gate no-7, following which four other gates were opened.
Sources said that the dam authorities opened 12 gates in phases, which released 1,80,000 cusecs of floodwaters.
Meanwhile, water level in the reservoir touched 619 feet. The maximum capacity of the reservoir is 630 feet.
About 5,59,941 cusecs of floodwaters were entering the reservoir, the dam authorities said, adding, there is no flood threat in the lower catchments due to the release of the waters.