Study on bank erosion and its impact on the livelihood of the local people: a case study along the Nabaganga river

Abstract

River bank erosion has been a recurrent feature along the large scale and some moderate scale rivers in Bangladesh. Though much research works on the socio-economic impact of bank erosion of large scale rivers have already been done, the moderate scale rivers often have been neglected in this respect. Nabaganga is one of such moderate scale rivers in south-west region of Bangladesh that has long history of bank line shifting according to the consent of the local people. Based on the socio-technical approach, this thesis provides an understanding on the rate of river bank erosion resulting from change in flow pattern in river bends and consequent effect on livelihood of the local people. The high amplitude meander at Chander Char and the moderate amplitude meander at Noagram have been selected as the study reach. A large portion of the high land has already been eroded by the river causing serious relocation problems for the inhabitants. Questionnaire survey and PRA tools (FGD and Seasonal Calender) had been conducted with partial and fully landless farmers, day labourers, small shopkeepers, women, old aged landless people, school teachers, the Union Parishad Chairman and the field officials of BWDB to take out the relationship between bank erosion and opportunities of maintaining their livelihoods in different time of the year. Reports of some completed as well as ongoing projects of the study area, maps, papers and cross-sectional data of the river served as the source of secondary data. Local people are loosing their land directly by bank erosion as well as acquisition of land for construction of retired embankment. From the information given by local people, the rate of erosion of Nabaganga is around 30-40 m/year. Based on the flow model and the erosion prediction model along meander bends adopted in this study, the estimated erosion at Chander Char and Noagram are around 34 m/year and 43 m/year, respectively, which is close to the range informed by the local people. So each year, due to continued loss of land, the small farmer becomes marginal and marginal farmer turns to landless. Thus the poorer strata are converging into the poorest strata. Thus increase of poverty is engulfing the socio-economy of the area. Most of the landless people, leaving the villages, shifted towards other villages, cities. About 20 to 25 households of both the villages who could not afford to shift anywhere else are passing their days on the embankment in great misery. They are searching different livelihood opportunities through the service of a day labourer, borrow farmer, shopkeeper, sand troller loader, collecting and selling water lily in the market and many other temporary income generating activities. From the month of June to October people suffer from lack of work. Dependable prediction of bank erosion can help the Government taking early steps in resettlement of the landless, suitable crop diversification and proper distribution of livelihood opportunities. There should be effective implication of the Government legislation regarding the resettlement process and land acquisition. In the water logged portion of the area government can release fish to encourage people in capture fisheries. Local people should be involved in all stages of development work like construction of embankment and bank protection work. This will help both increasing their employment opportunities as well as better O&M of the work. Further study can be conducted on if the flow of the river Madhumati can be regulated at the upstream of the Halifax cut to minimize the erosion of Nabaganga. Above all there should be an erosion mitigation plan of the Government for better management of the situation.