The Jamuna river has been the most ferocious in eroding its banks, gobbling up 919,889 hectares (ha) of land in eight northern districts between 1973-2016, a study based on satellite images by the Centre for Environmental and Geographic Information Services (CEGIS) showed.

The river carries the flows of the Brahmaputra downstream in Bangladesh after entering the country from Assam at Noon Khawa in Kurigram. The Ganges, which becomes the Padma after entering Bangladesh in the north-western district of Chapainawabganj, was no less mean. It has swallowed 91,888 ha of land, including human settlements and croplands, the study showed. Both the Jamuna and the Padma join together to form the Meghna, near Chandpur in the south-east, flowing down to the Bay of Bengal.

The district worst affected by the Jamuna was Sirajganj. It lost 23,410 ha during the period.

"We have identified 29 vulnerable locations along the Jamuna, Ganges and the Padma. Of these, 20 were found along the Jamuna in 2017, 10 each on its right and left banks," Dr Mominur Rahman Sarker, deputy executive director of the CEGIS, told the Independent yesterday.

He said the CEGIS has not only been working in Bangladesh, but also helped two neighbouring countries, India and the Nepal, in identifying vulnerable spots along the Ganges and the Koshi river that flow into them from Nepal in 2015-16, extending the centre's know-how in using satellite images to locate vulnerable points of erosion along the rivers.

Sudipta Hore, an information specialist of the CEGIS, said they were extensively using images from the LAND SAT satellite of NASA of the US and the INSAT satellite of India in identifying vulnerable locations of the major rivers chewing up land in  Bangladesh.

The 14 districts are  Kurigram, Gaibandha, Jamalpur, Bogra, Sirajganj,Tangail, Pabna, Manikganj, Nawabganj, Rajshahi, Rajbari, Kushtia, Faridpur and Shariatpur. They are menaced either by the Jamuna or the Ganges-Padma.

Following this year's floods, erosion by the Jamuna and the Padma have become severe.

Hore said they are working on the problem.