Flood situation in the country's northern districts had turned severe as Teesta swelled over all-time high of 55 centimetres (cm) over the danger mark on Monday early hours.
Onrush of upstream water from the neighbouring India caused such sudden surge from 12.05 am on Monday, executive engineer at Daliya Division of Bangladesh Water Development Board Md Rabiul Islam, told the FE.
He said the Teesta swelled over its danger mark by 55 centimetres which is a record.
He said "We declared an alert in the Dimla in Nilphamari and Hatibandha in Lalmonirhat as we had a plan to open the flood bypasses."
But the water level declined to some extent after few hours which helped to keep the bypasses remain shut, he said.
He said the barrage has a capacity to pass 0.45 million cusec of water.
“If it crosses 0.45 million cusec, we usually opens flood bypass. But all of the 44 sluice gates of the barrage are open from the last week of June’.
However, Teesta was flowing 52 cm over the danger mark on Monday noon, said flood forecasting and warning centre(FFWC).
Nearly 10,000 families are at seven inundated unions of Dimla upazila on Monday.
Fresh areas in Nilphamari, Lalmonirhat, Kurigram, Rangpur, Gaibandha, Bogura, Natore, Jamalpur, Kishoreganj, Sunamganj, Sylhet, Shariatpur, Faridpur, Madaripur went under flood water as major rivers continued to flow over their danger mark.
So far 1.5 million people have been marooned in flood affected 401 union of 81 upazilas under 19 districts, according to National Disaster Response Coordination Center (NDRRC).
As the flood inundated many low-lying areas in northern and northeastern regions over the past few days, marooned people have taken shelter on embankment, roads, highland and flood centres with their domestic animal and valuables.
Because of heavy rainfall and upstream water from bordering areas, the water flow Brahmaputra-Jamuna and Padma river basin have been increasing rapidly on the day which might continue for next 72 hours, said FFWC.
Padma River is in rising trend might and will continue to swell for next 24 hours. It might cross danger mark at Vagyakul, Mawa points in Munshiganj in the next 24 hours, said FFWC.
River water rose at 78 of the 101 points observed by the warning centre in the morning of Monday.
Fourteen major rivers were flowing above their danger marks (DM) at 22 stations on Monday, according to FFWC.