Surging water of these rivers is spreading in low lying areas of Patna, Bhojpur, Khagaria and Bhagalpur districts.
Rail and road traffic have also been disrupted in many places due to torrential rains.
Chief Minister Nitish Kumar has held a meeting with the Disaster Management officials on the flood situation in the state.
The Chief Minister has instructed flood-fighting authorities to be on high alert. The MET department has also predicted torrential rains in 19 districts including Gopalganj, Purnea, Katihar Buxar.