In an advisory, the CWC said the Barak river is expected to flow in "moderate to high flood situation" in the state of Assam and neighbouring Meghalaya and Manipur over the next few days.
"In view of heavy to very heavy rainfall in the state of Assam and adjoining Meghalaya and Manipur in Barak Basin, (water level in) river Barak and its tributaries is rising in Assam which is affecting (its) districts of Cachar, Hailakhandi and Karimgunj," Union Water Resources Ministry said in a statement here.
"The rivers Barak, Katakhal and Kushiyara are expected to flow in moderate to high flood situation in the next two to three days. District administrations have been advised to take all precautionary measures," the advisory said.
Earlier in July-August, Brahmaputra's tributary Dhansiri flowed above the danger mark at Numaligarh in Golaghat district in upper Assam.
Among the affected eight districts, Jorhat was the worst-hit with over 25,000 people impacted till early August, followed by Dhubri and Barpeta districts. At least 65,000 people were affected by the flood.
