Surface Water Quality Appraisal and Suitability Assessment for Designated Uses along the Brahmani River Basin, Odisha, India

The Brahmani River in Odisha supports regional agriculture, industry and domestic supply but human activities are mounting pressures on the water quality of the river. The paper measures the spatio-seasonal variability in the surface-water quality between 2017 and 2024 by using the samples obtained in 12 monitoring stations during pre- and post-monsoon periods. The main parameters that were examined to describe hydrochemistry and their suitability for use were core physico-chemical parameters (pH, dissolved oxygen, biochemical and chemical oxygen demand, total dissolved solids, major cations, and anions). The overall status was calculated in terms of the Canadian Council of Ministers of the Environment Water Quality Index (CCME-WQI), and agricultural usability was assessed using common irrigation indices, which are sodium adsorption ratio (SAR), soluble sodium percentage (SSP), permeability index (PI), Kelly ratio (KR), magnesium adsorption ratio (MAR) and residual sodium carbonate (RSC). It was observed that some quality deterioration occurred locally and was in line with the discharge of urban and industrial wastewater into the basin. The type was predominant and the hydrochemical facies was characterized by carbonate weathering with minor evaporite effects.