Monitoring the spatio-temporal impact of small tributaries on the hydrochemical characteristics of Ramganga River, Ganges Basin, India

Abstract

ABSTRACTSurface waters are one of the most easily pollutable natural resources because of their high mobility and universal solvent nature. One of the most severe environmental problems is the deterioration of the surface water quality due to rapid industrialization and urbanization. In India, surface water pollution is a major problem. The Ramganga River Basin, an essential sub-basin of the Ganges Basin, has been facing water quality problems as it flows through a densely populated and a large industrial area of Uttarakhand and Uttar Pradesh in India. This study focused on the impact of smaller tributaries, namely Binau, Gagas, Deota, Mandal, Kho, Phika, Dhela, Kosi, Bhakra and Baigul on the hydrochemical characterization of the Ramganga River which in turns affects the water quality of the Ganges River. To this end, water samples from 10 tributaries of the Ramganga River were collected and analysed during the pre-monsoon, monsoon and post-monsoon periods of 2014. These water samples were analysed to determine various physicochemical and heavy metal characteristics. Concentration of turbidity (2252 NTU), electrical conductivity (EC: 975 µS/m), total dissolved solids (TDS: 529 mg/L), fluoride (F−: 3.47 mg/L), calcium (Ca2+: 108 mg/L), bicarbonate (HCO3−: 360 mg/L), iron (Fe: 126.58 mg/L), manganese (Mn: 2.490 mg/L) and chemical oxygen demand (COD: 77.98 mg/L) in the middle and lower regions of the Ramganga Basin, found to be higher than their prescribed limits of World Health Organization (WHO). These results could be due to increased effluent loading from wastewater discharges from the nearby urban settlement, sacred mass bathing points and agricultural runoff in tributaries.