The low-lying areas of Bagerhat, Jhalakathi, Bhola, Satkhira and Khulna districts have been inundated due to the tidal surges caused by the depression over the Bay.
In Bagerhat, the residents of the coastal areas have been suffering a lot for the past three days due to intermittent rainfall.
The water level of Bhairab, Baleshwar, Panguchhi and Pashur rivers increased by two feet from normal ton Monday afternoon while water in Sundarbans was flowing 3-4 feet higher than normal.
The wildlife were seen wandering in search of a safe place.
All the ponds in Sundarbans have overflowed and if the situation continues for more days, the fish enclosures in Bagerhat coastal areas may be washed away anytime.
Meanwhile, a number of fishing trawlers with fishermen have taken shelter at Dublarchar, Narikelbaria and Katka of Sundarbans as the sea is very rough.
Amaresh Chandra Dhali, in-charge of Mongla Weather Conservatory Centre, said the weather office has recorded 21 mm of rainfall in three hours from 6 am to 9 am in Bagerhat.
In Bhola, the water level of many rivers in the district has increased by 2-3 feet above its normal level, rendering 20,000 people marooned.
Besides, the ferry services on Bhola-Laxmipur route have been disrupted as the ghat went under water.
Meanwhile, the residents of Madanpura in Doulatkhan, Char Jahiruddin of Tajumuddin, Dhalchar and Char Kukri-Mukri in Charfassion upazilas and Kolatoli of Manpura upazila of the district have been flooded due to the tidal surge.
Abdus Salam, chairman of Dhalchar union in Charfassion upazila, said the union is home to 12,000 people and they have been passing through untold sufferings for the last couple of days as the river water inundated their residents.
Besides, Mahbubur Rahman, an officer of Bhola Weather Conservatory Center, said 38 mm rainfalls have been recorded in the past 24 hours till Monday noon.
In Satkhira, the inhabitants of the coastal area of the district have been experiencing showers from Monday morning triggered by the depression in the Bay of Bengal.
Already 200 bighas of fish enclosures have been washed away while 62-km of embankment in 35 points of the coastal areas was at risk of collapse.
Shahnewaz Dalim, chairman of Khazra Union in Ashashuni upazila said, 200 bighas of land have been washed away in the upazila.