The water quality and pollution sources assessment of Surma river, Bangladesh using, hydrochemical, multivariate statistical and water quality index methods

Abstract

Currently, the water pollution is an important issue in Bangladesh as well as in the world. The Sylhet city in Bangladesh is suffering from lack of structured sewerage and drainage systems with somehow improper management of solid wastes. Consequently, such wastes are discharged into the nearby Surma river through different sources responsible for degrading the quality of water. Thus, this study focuses on exploring the present water quality of Surma river applying the hydrochemical, multivariate statistical methods, and also with the help of the Water Quality Index (WQI) analysis. Also, recognize the potential pollution sources of water in the study area. The outcomes show that the average values of some components such as pH, Dissolved Oxygen (DO), Iron, Total Dissolved Solid (TDS), and Total Solid (TS) are found within the standard limit. Whereas, the Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), Carbon di-Oxide (CO2) and turbidity are found higher than the standard limit. The Pearson correlation coefficients reflect some strong positive associations with moderate to negative correlation, suggesting the heterogeneous sources and pathways of the contaminants and ions. The highest factor loading values recorded against TDS, DO, BOD, COD, pH, and turbidity suggests them as a key environmental contaminants. The WQI value suggests that the poor water quality exist in the river. Particularly, the middle stream of the river is much polluted as this area largely covered by the Sylhet City Corporation (SCC). This study recommends that there should be a strong management plan with monitoring cell for maintaining the water environment in the SCC area.