Why we cannot prevent riverbank erosion disaster despite better technology

Experts have predicted riverbank erosion in an area of 28 square kilometer in 13 northwestern and central districts this year, and called for protective measures for structures and farmlands. However, they forecast less torrential rains and onrush of water from the upstream this season. According to a news report published in a national daily on Friday, experts at the Center for Environment and Geographic Information Services (CEGIS) pointed out that the riverbank erosion disrupts economic activities in the country by displacing thousands of people every year. These displaced people end up in slums in the capital and other cities.
A public trust under the Water Resources Ministry, CEGIS said its studies on river morphology in 2021 suggest that particular locations in 13 districts could be exposed to more erosion in coming months. Its prediction, as it claims, has proved to be an effective Disaster Risk Deduction (DRR) measure for reducing economic damage and people’s suffering caused by the riverbank erosion. Its prediction helps the national agencies responsible for river management, local government and people living along the banks of the major rivers for disaster decision-making. Last year, the CEGIS predicted damage of 24 kilometres in river erosion, but actually an area of 38 kilometres was devoured by erosion.  
Since 2017-19, erosion took away a total of 1700 kilimetres of riverbank, displacing about 17 lakh and 15 thousand people. Evaluation of the predictions for the last few years showed a reasonably good match with the occurrences. The CEGIS is predicting riverbank erosion one-year before such disaster. In addition, it has also developed tools for predicting riverbank erosion before two years for the Jamuna, the Ganges and the Padma Rivers in the last three years. Several other major rivers like the Teesta, Dharla, Dudhkumar, Korotoa; and Ichamati also come under the purview of the CEGIS study. Erosion peaks during the June-to-October monsoon season, which brings torrential rains and swells the country’s rivers.
Erosion of banks of our meandering rivers is an age-old recurring disaster. With the improvement of technology forecast of the disaster has improved. Till such time as riverbanks stabilise the authorities must take measures to prevent erosion and ensure the safety of life and property.