The Padma, the Ganges and the Jamuna have taken away around 1.5 lakh hectares of land but returned only 53,000 hectares in the last four decades.
In other words, the country has lost to the three rivers around one lakh hectares or 1,000 square kilometres of arable land, which is more than the size of Dhaka city, according to a study of the Centre for Environmental and Geographic Information Services (CEGIS).
River erosion has also been affecting two to three lakh families each year with one third of them becoming destitute, said experts at a discussion organised by The Daily Star at its conference room yesterday.
The government doesn't pay much attention to the issue, and the victims never get much help from the state to find an alternative livelihood, they said.
When chars emerge in the rivers where erosion is intense, social conflicts and violence become the way of life in the locality.
“The rivers erode valuable productive croplands or townships. But the chars that emerge in the rivers are sandy and not fertile. There should be a long-term planning to deal with river erosion and its victims,” said noted hydrologist Ainun Nishat.
If the erosion of banks of all rivers is taken into account, the figure would cross two lakh hectares, experts said.
In his presentation, CEGIS Deputy Executive Director Maminul Haque Sarker said among the three rivers, the Jamuna devoured 90,367 hectares of land along both its banks but returned only 16,444 hectares.
“Most of the land has been lost to the Jamuna that has widened over the years. The river is five to 12 kilometres wide,” said Maminul.
Croplands, houses, mosques, temples, roads, schools and offices have been lost to the Jamuna that flows through Kurigram, Gaibandha, Jamalpur, Bogra, Sirajganj, Tangail, Pabna and Manikganj.
Nishat said the Jamuna is a young river, and its erosion and accretion will continue. This means the river needs training, as there are communities and arable land on both its sides.
On resettlement of the victims, Nishat suggested establishing well-organised townships on river banks and protecting those.
The Ganges ate into 29,842 hectares of land in Nawabganj, Rajshahi, Natore, Kushtia, Pabna and Rajbari and returned 25,009 hectares.
At one point in Rajshahi, the Ganges has shifted nine kilometres from its original course, said Maminul.
The Padma eroded 33,229 hectares of land and returned 11,545 hectares in Manikganj, Rajbari, Faridpur, Dhaka, Munshiganj, Madaripur, Shariatpur and Chandpur, he said.
“In the '80s, erosion in those rivers was more intense than the present time,” he added.
Analysing satellite images, the CEGIS makes predictions on land erosion of the three major rivers at the start of monsoon every year. This year they predicted that around 3,600 hectares of land would be lost to the three rivers.
Shamsul Huda, executive director of the Association for Land Reforms and Development, said two to three lakh people become victims of river erosion every year, and one third of them become destitute, losing all savings and properties.
“The government should have a long-term plan to resettle and rehabilitate the people,” he said.
Some 80 percent of the 50 lakh acres of khas land is illegally occupied mostly by political and social elites. And the government is not interested in implementing its policy of distributing khas land among landless people, he added.
Selim Bhuiyan, director general of the Water Resources Planning Organisation, said the Water Development Board sometimes has to work on political consideration and the work proves ineffective.
There are problems in getting funds released in time for building or repairing embankments, he added.