Only dredging is not the solution

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Rayhan Ahmed Topader :
Padma is a name for the sacred lotus flower, a symbol of beauty, purity, and growth. The meaning is well-suited for the river bearing the same name, which seems to be constantly evolving and changing in beautiful ways. That is a mixed blessing for the people who live nearby. The Padma is one of the major rivers of Bangladesh, and satellite imagery shows that it has been growing in size, transforming in shape, and changing in location for at least the past 30 years. It forms in India at the junction of the Ganges and Jamuna Rivers, then merges with the Meghna River and ultimately empties into the Bay of Bengal. Rivers in the country, mainly the small and medium sized ones, are being filled up from bank-side; land is developed for various purposes, mainly to build shops, construction yards, depot of sand, cement or lumber, homesteads, etc. Such processes of encroachment of the river are controlled mostly by the politically powerful. From many such rivers, water is pumped out during the lean season, either to cultivate paddy, onions, or oil seeds on the bed of the rivers. Water is also pumped to irrigate nearby plots, drying up the rivers. This has been done all over the country. Although we get some paddy out of the process, the natural production of freshwater fish is totally destroyed. These rivers remain dry till April and May the breeding period of fish. Therefore, fish migration/spawning is obstructed. The same happens to the beels and jheels.
Many wetlands in Tangail, Sirajganj, Pabna, Faridpur, and Gopalganj, once rich habitats of aquatic life, are now devoid of fish. Untreated liquid industrial effluents are being discharged into rivers indiscriminately, especially around urban areas, leaving these rivers biologically dead as the level of dissolved oxygen a must for the survival of fish and other aquatic animals. It is essential for protecting the Padma river banks, to prevent further erosion and allow for land reclamation along the Padma to recover the flood plain land lost in past decades. furthermore, important aspects to consider comprise but not limited to water management, including irrigation demands, canal digging, flooding, water quality and minimum flows, sediment management, bank stabilization, navigation, social aspects, like the condition of the char people, fisheries, ecology, bio-diversification, institutional , economical, Job opportunities and employment generation aspects. Impacts of river bank erosion are multifarious namely social, economic, health, education and sometimes political. The first and foremost impact is social i.e., homeless due to land erosion which compels to migrate. After forced migration they suffer from economic crisis, namely loss of occupation and loss of property, and they are at loss of property and sometimes involvement in criminal activities. Identity crisis is inevitable to these migrated people as the belongingness to any particular district or country is often denied.
Due to the geographical location of Naira on vast flat plain at the edge of the main river Padma, the livelihoods of the poor people are fundamentally affected by water-related disasters including riverbank erosion, floods, cyclones and tidal surges. Riverbank erosion is one of the most prominent disasters in Naria, caused by dynamic channel shifting of this river. In this year, 2018, it affects more than 5000 families including the poor, who face significant social hardships, such as loss of homestead, lands, and /or farm crops, and being displaced to the riverine fringe land, char lands, or urban slums. Therefore, enhanced river bank erosion is essential for the poverty reduction and economic growth of riverine areas at Naira in Shariatpur district.The Padma is recognized as one of the major rivers in Bangladesh arising from river bifurcation of the Ganges, being the distributaries of it. In terms of average annual discharge and classified as the third largest river in the world, only surpassed by the Congo and Amazon. The Padma meanders its way to the Bay of Bengal from the Himalayas through Shariatpur district. It erodes on bank and build chars on the other. Perhaps this year has been the single-worst case of riverbank soil erosion in a hundred years, the Padma has ravaged vast swathes of Naria a little more than 22 Km downstream from the Padma bridge project.It has changed abruptly for sure, once relatively calm and quiet in the area, it turned into an all- devouring river in just a few months in a year.
People there are on edge as the Padma changed its course and have been gobbling up village after village, making many well off people penniless overnight. Recently, more than 5,000 families of six unions and one municipality of Naria Upazilla have lost their homes, farmlands, and the hungry tide still now threatens to swallow the important and valuable infrastructures in areas and more than 12 villages of six Unions are under threat.
Naria upazilla under shariatpur district had been on the good side of the Padma. The river used to erode its left bank but it has started eroding its right bank five to six years ago and people have become worried as the erosion has reached the densely populated and important business locations. According to hydrology expert Ainul Nishat, The Padma flows of her own accord; you cannot understand Padma with mathematics or science. River erosion is a natural matter. The erosion may continue for two years in this location. In order to take preventive measures, we have to understand the scale of Padma. What works to prevent erosion in the Gorai, Madhumati, or other small rivers will not work on Padma. According to the online publishing outlet for NASA, hundreds sometimes thousands of hectares of land erode and fall into the Padma every year. Since1967, more than 66, 000 hectares (256squre miles) have been lost- roughly the area of Chicago” says the report published in August, 2018. As per remarks of some Thematic Experts of Water Management, the Padma Bridge design study has looked at the long term erosion patterns, and the current erosion might be part of it.
The Padma Bridge construction might alter the river course in future, but the river training works is designed to not interfere with the river downstream (and upstream). There were very little impacts downstream estimated. The river stabilization plan presently being prepared contains some ideas about what to do in this area, but is cautious as it recognizes the impact of the Padma Bridge river training works, which are not fully quantifiable. Think about the impact of the Bangabandhu-Jamuna Bridge, as we know it now and what was thought the impact would be during the time of design and construction .CEGIS has done the Padma Bridge study, been involved in the formulation of the river stabilization plan, and is conducting annual erosion prediction, so is very qualified in providing advice. CEGIS is currently updating the morphology for the Padma Bridge. Some observations can be made upon inspection of changes in total width of the Padma river are without appreciable delay reflected in changes in water, sandy and vegetated char land. Char area are shows a higher sensitivity to the widening process than the water area taken by the low flow channels and both sandy and vegetated areas increases when the width of the river increases. Special care is required from the Government side for the preparedness of padma riverbank erosion protection embankment for preventing from riverbank erosion at Naria on an urgent basis and the attention should be needed to safe the affected people in a sustainable way.
However, if we go for properly planned and designed ‘river management’ projects that include bank revetment, ‘river training infrastructures’ and plans to dredge in appropriate reaches, then we may find the right solutions. Again, this exercise should be carried out in a phased manner so as to enable the ‘observe and learn’ approach. Dredging of small rivers, however, poses much less of a challenge. We have the appropriate constitutional provisions and necessary laws for taking action against encroachers and polluters. I believe that it is possible to do so if the administration is fully committed to save our rivers. The governments of India and China are cleaning up their rivers; they are using modern technology such as Remote Sensing and Satellite Monitoring to monitor the conditions of the rivers. Developed countries are using proper monitoring mechanisms of maintaining the acceptable level of river water quality. I believe that we have the capacity to restore our rivers. In recent years, Padma’s erosion rates, sinuosity, and braiding have decreased. Erosion slowed as the meandering bends disappeared due to sedimentation and chute cutoff when the water flows across the land instead of following the curve of the river. But that does not mean the area is free from erosion. Any disturbance in the ecosystem, such as floods, landslides, or construction, could influence the morphology of the river.

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