Analysis of physical changes and socio-economic impact due to siltation of the Kopotaksha river and its adaptive measures

Abstract

Rivers have been the major sources of fish production, livelihood resources, biodiversity, etc., in Bangladesh from time immemorial. Siltation is one of the major problems in the river system of Bangladesh. The River Kopotaksha was one of the main arteries of the water resources system located in the South-Western region of Bangladesh. This research explains a tragic story caused by siltation induced physical change and associated socioeconomic impact of the Kopotaksha River. A study has been carried out in three villages (Chakla, Vorotpur, and Kismotchakla) of Monirampur Thana of Jessore District and two villages (Pakuria and Diara mathpara) of Kalaroa Thana of Satkhira District, Bangladesh to find out the overall situation. Necessary data were collected through direct observation, questionnaire survey, application of PRA tools and analysis of secondary data. The result of the study reveals that adverse impact of coastal embankment project, low flow due to Farakka barrage, local obstacles, high salinity, growth of profuse water hyacinth, etc., in the river facilitated deposition of sediment in the river and gradual siltation created a hump on the riverbed. During the period 1994-2001 the cross-sectional area, width, average depth and conveyance capacity of the river decreased up to 95, 58, 88 and 99 percent, respectively, along the river reach, which deteriorated the drainage capacity of the river and created severe water logging. With repeated failure in crop production, the socioeconomic system of the area began to collapse. People lost their land under water and majority of the agro-based community became landless and financially shattered. Most of the people turned from agricultural to non-agricultural profession. The average income decreased by 15% and expenditure increased by 14% as they have to spend excess money for renovation or construction of homestead, buy fuel for cooking, medicine for diseases, fodder for livestock, etc., and for this they have to take loan at a high rate of interest. Different types of social problem are also emerging i.e., social crime, social instability, early marriage, migration, etc., which weaken the social relationship. People faced different diseases as the water quality degraded, latrines were damaged and the distance to the source of suitable water increased. Water logging appears to be a rather ‘new phenomenon’ and there is no permanent solution to reduce such impact has been adequately addressed. Now the local people try to struggle and adapt with alternative option for income, living, cooking, communication, water use, etc. In the absence of a long-term solution to the problems, short-term adaptation measures could have been designed. Illegal ponds, ghers, obstacles should be removed or developed in a systematic way which can not disturb the natural condition of the river. On the other hand, creation of job opportunity will solve the socio-economic problems in the study area.