National, Back Page

Climate change causes riverbank erosion

Published : 29 Aug 2019 10:16 PM | Updated : 07 Sep 2020 12:59 PM

Riverbank erosion across the country has taken serious turn rendering lakhs of people homeless. Besides, the erosion is also destroying crops land, government establishments, non-governmental offices and educational establishments. Experts pin the blame for this worst situation on climate change. About 700 rivers, including their tributaries flow through Bangladesh, constituting a waterway of total length of around 24,140 kms. Government has taken initiatives to construct embankments, conduct river dredging and embankment forestation. Bangladesh is projected to lose around 2,270 hectares of land this year due to riverbank erosion, a study report has said. Every year in Bangladesh, riverbank erosion leads to millions of people being affected as it results in damage and loss of crops, cattle, housing structures, and farmland.

Additionally, it erodes away public infrastructure and communication systems. The unpredictable shifting behavior of the rivers and their encroachments not only affect the rural floodplain population but also the urban growth centers and infrastructures, says Abdul Mazid, an environment specialist. Mentioning the long-term effect of climate change on river erosion Abdul Mazid said that, “riverbank erosions often cause loss of crops, seeds and agricultural land, which may affect the quality and quantity of the harvest and exacerbate food insecurity.”

According to the Bangladesh Water Development Board (BWDB) the most erosion-prone districts are Bagura, Sirajganj, Kurigram, Lalmonirhat, Gaibandha and Rangpur, in the country’s north, and Chandpur, Manikganj, Rajbari Shariatpur, and Faridpur in Dhaka zone, with Tangail and Jamalpur in Mymensingh zone, and the coastal areas of Patuakhali. The most erosion-prone area in Bangladesh is Sirajganj, which faced a total land erosion at a rate of 622.2 ha, according to a (Center for Environmental and Geographic Information Services) CEGIS study. “The Government of Bangladesh and International NGOs must prioritize the quick restoration of livelihoods across river-erosion affected areas. They must be more proactive in identifying urgent food security and livelihood projects that will provide income-generating opportunities for communities, as well as reestablish assets.” says Professor and Environmentalist Nazrul Islam.

Most of the country’s land is formed through silt brought by the rivers. Additionally, Bangladesh is in a monsoon climate zone facing heavy rainfall and flooding. Where there are no well-constructed embankment of a river, the soil can be eroded due to heavy rainfall and flooding. Due to climate change, the rainfall pattern is ever changing and it triggers abnormal flooding. Such flooding in addition to increased flow of river water from the upper catchment areas increases the intensity of riverbank erosion.

Riverbank erosion can take place, both, during flooding and after the water recedes. Cegis has predicted 22 probable vulnerable locations for this year along both banks of the Jamuna, the Ganges and the Padma rivers which are vulnerable to riverbank erosion. Since 2004, Cegis has been predicting riverbank erosion in the major rivers in Bangladesh with adequate accuracy in collaboration with the Bangladesh Water Development Board (BWDB).

In 2017, Cegis predicted 29 locations out of which 20 are in the Jamuna, five in the Ganges and four in the Padma rivers. In September 2018, over 13,000 people of Naria upazila became homeless due to the erosion by the Padma. At least 200 businesses at Sadhur Bazar and 200 shops at Wapda Bazar disappeared in the Padma. The Cabinet Committee on Economic Affairs in November 2018 approved a proposal to protect Zajira and Naria upazilas of Shariatpur from river erosion at a cost of Tk 1,077.58 crore.