A Canadian Water Quality Guideline-Water Quality Index (CCME-WQI) based assessment study of water quality in Surma River

摘要

Water quality of Surma River is frequently deteriorating for the last few decades since ever-growing human activities, poor drainage facilities, and direct disposal of industrial and municipal waste. Along with poor structure, natural canals (local nameChara) are responsible for the conveyance of surface runoff from its urban catchments to the receiving Surma River. The purpose of this study is to assess the degree of pollution in context of CCME-WQI (Canadian Water Quality Guideline-Water Quality Index) in Surma River by determining various physico-chemical parameters. Data from sample analysis, the concentration of DO (Dissolved Oxygen), BOD (Biochemical Oxygen Demand), TSS (Total Suspended Solid), Turbidity and Fe (Iron) do not meet the satisfactory level. Particularly this study suggested that water quality of this river is affected for high turbidity and BOD due to soil erosion, runoff and municipal effluent discharge without any treatment. Beside these, concentration of heavy metals in Surma River is a bit high which poses another impact for the user of Sylhet city whom are mainly dependent on Surma River. Surma River is found to 15.78 according CCME-WQIs model which indicates that water quality of this river near Sylhet city is Poor and frequently impaired.