Floods could hit the Brahmaputra and Meghna river basins in July and August this year. The Flood Forecasting and Warning Centre (FFWC) has warned of the risk because of heavy rain upstream.

Sardar Uday Raihan, executive engineer at the Bangladesh Water Development Board's (BWDB) Flood Forecasting and Warning Centre, told the media that for climatic reasons Bangladesh always faces a flood risk in July and August. Heavy rain falls in the basins of the country's main rivers and upstream at this time, causing floods in the country.

That, he said, is why there is a risk of floods in the Brahmaputra and Meghna basins this July and August.

Historically, the country's most devastating floods have come in this middle part of the monsoon. In August-September 1988, heavy rain caused a catastrophic flood that inundated about 82,000 square kilometres, around 60 per cent of the country's land.

Similarly, the 1998 flood lasted more than two months through July and August. More than 1,000 people died and about 3 crore (30 million) people were temporarily displaced or stranded by water.

Experts believe the biggest risk is high flows in the two large basins, the Brahmaputra and the Meghna, at the same time. In late July 2004, the peak flows of the Brahmaputra and Meghna coincided, causing a severe flood that inundated about 30,000 square kilometres in the north-east alone.

In addition, the 2022 flood in the Meghna basin and the devastating 2024 flood together affected more than 1.3 crore people, which makes the growing risk of heavy upstream rain even clearer.

Sardar Uday Raihan said the FFWC can now forecast floods 10 to 15 days in advance for the country's inland river basins, but only three days in advance for coastal rivers.

On the current state of the rivers, he said low-lying areas of the Brahmaputra basin are being flooded, but the situation may stabilise within the next five to six days.

With no heavy rain in the basin or upstream, the Meghna basin will remain stable for the next few days, the FFWC executive engineer said. But a low-pressure area may form in the Bay of Bengal this month, which could cause flash flooding in low-lying coastal areas.

The flood forecast published by the FFWC on Thursday said water levels in the Brahmaputra-Jamuna river system had fallen in the previous 24 hours, but could rise over the next four days and remain steady on the fifth day.

The forecast said that from 4 to 7 July (the second to fifth days), the Brahmaputra-Jamuna could flow at warning level in Kurigram, Gaibandha, Jamalpur and Bogura districts, possibly flooding some adjacent low-lying areas.

It added that water levels in the Ganges-Padma could keep rising over the next five days, but would stay below the danger level.

Over the next 72 hours, the Surma-Kushiyara (Upper Meghna) rivers could flow at warning level in Sylhet and Sunamganj districts, so some adjacent low-lying areas may remain flooded.

At present, the Teesta at Dalia in Nilphamari and at the Tarapur point in Lalmonirhat, the Kushiyara at Fenchuganj in Sylhet and Markuli in Sunamganj, and the Someshwari at Kalmakanda in Netrokona are flowing at their respective warning levels.

Source: Jagonews24. First published in Bengali on The Agro News.