Assessment of seasonal impacts on Water Quality in Yamuna river using Water Quality Index and Multivariate Statistical approaches

This study analyzed the water quality of the Yamuna river in Prayagraj across nine locations where the sampling was done upstream, downstream and middle stream from May 2019 to April 2020 using fourteen water quality parameters. Quarterly samples showed good Water Quality Index (WQI) values for summer (95.19), monsoon (77.28), and winter (90.77), but a decline in spring (102.11) due to religious activities was observed. Inductively coupled plasma mass spectroscopy suggested high concentration of Ca²⁺, Mg²⁺, K, and P in the river. Principal Component Analysis revealed 9 significant factors (eigen value >0.5) covering 25.13 – 93.89 % variance. Strong correlations included TDS-EC (0.853) and Ca²⁺ – Mg²⁺ (1.00) was observed. The correlation between water quality parameters generated by principal component analysis showed that the main parameters affecting the water quality vary in all the seasons. Based on the water quality indicators, anthropogenic activities are accountable to deteriorate the quality of river water. Therefore, the pollution status of the river need to be made publicly.