River erosion may eat up 28sq km area

Rivers are likely to erode about 28 square kilometres of land this year, which is more than the land eroded last year, according to a research body of the water resources ministry.

The Jamuna, the Ganges and the Padma will aggressively erode their banks in at least 13 districts, said a report from the Center for Environmental and Geographic Information Services (CEGIS).

At least 24 sq km of bank disappeared into the rivers in 2020.

The latest report titled Riverbank Erosion Prediction for 2021 said Madaripur might be the worst-hit district where 9.54 sq km of land will be gone in the coming months.

The other particularly vulnerable districts are Kurigram, Jamalpur, Gaibandha, Bogura, Sirajganj, Tangail, Manikganj, Pabna, Kushtia, Rajbari, Rajshahi, and Faridpur.

In Tangail, 4.94 sq km of land will be eroded. In Gaibandha and Rajbari, the researchers predict that people will lose 2.91 sq km and 2.88 sq km of land respectively.

Riverbank erosion is one of the major natural disasters in Bangladesh as it makes thousands of people homeless and landless every year.

The damages done to the banks by the frequent and prolonged floods last year will have an impact on the erosion this year, the body warned.

Sudipta Kumar Hore, associate specialist of river, delta and coastal morphology division at the CEGIS, said last year's floods were "extreme events".

Such floods leave numerous channels flowing inland, making the banks more vulnerable to erosion in the next monsoon, he said, "That's why the prediction for riverbank erosion is higher this time."

CEGIS developed a tool that uses a series of satellite images to predict the path of erosion by the Jamuna, the Ganges and the Padma.

Since 2004, the methods have been applied to predict river erosion and morphological changes of the Jamuna, the Padma and the Ganges by officials of different projects of the Bangladesh Water Development Board and Water Resources Planning Organization.

The latest CEGIS report said 3.7 km of embankment and one and a half km of roads are vulnerable to erosion this year.

"It was observed that erosion predictions made in the previous year showed a good match with the occurrences although there were few locations of slight riverbank erosion where erosion was not predicted.

However, the overall accuracy of this prediction tool is approximately 70-80 percent," the report reads.

This year's report predicted 20 probable vulnerable locations along the banks of the Jamuna, the Ganges and the Padma rivers.

Of the locations, 14 are along the Jamuna, five along the Ganges and one along the Padma.

The report includes information about the vulnerability of land, settlement and other physical infrastructures at the locations.

Experts say structural interventions to protect properties from riverbank erosion are very costly. As a result, structural measures, combined with non-structural ones like erosion prediction, can be used to reduce the loss and lessen the sufferings of people.

Kabir Bin Anwar, senior secretary of the water resources ministry, said, "We are aware of the situation and have been working on it since April. Cyclone Yaas has damaged some embankments but we have started repairing those."

Departments in the districts concerned are prepared to limit the damage.