The present study provides surface water types and water quality indices (WQI) for 70 large coastal rivers of the Western Ghats (WG) using Pearson correlation analysis of major ions and Gibbs plots. It appears that water composition of these rivers is the result of the interaction of rock and precipitation and ionic contributions from precipitation and chemical weathering of rock-forming minerals determine water quality. About 86% of the surface water samples are found to be suitable for irrigation (KR < 1) in non-monsoon seasons. Rivers near to Goa coast are only found unsuitable (KR > 1) for irrigation exclusively during non-monsoon seasons. Overall, the calculated WQI for studied rivers showed excellent to good water quality for drinking, agriculture, and aquatic life in monsoon seasons, which are then ranked from good to marginal in non-monsoon seasons. This biodiversity hotspot is facing high population pressure and anthropogenic activities. Despite it, quantitatively, all the physical parameters and chemical constituents are within the permissible limits of the World Health Organization (WHO) and Bureau of Indian Standards (BIS), thus making it suitable for drinking and domestic purposes.
Citation: S. Kiran Kumar Reddy & Harish Gupta & D. Venkat Reddy & Devender Kumar, 2021. Environmental Science and Pollution Research 28:38613–38628 ,