Application of multivariate statistical analysis and water quality index for quality characterization of Parbati River, Northwestern Himalaya, India

Abstract

The present study is an attempt to accomplish the understanding of the factors impacting Parbati river water quality in Kullu district of Himachal Pradesh. The main objective is to assess the overall water quality, to explore its hydrogeochemical characteristics including major ion contents and other chemical parameters using Water Quality Index (WQI), statistical techniques (principal component analysis) and conventional graphical representation such as Piper trilinear diagram, Durov. Eighteen surface water samples were collected from different altitudinal sites to analyze physico-chemical parameters for June 2019 and September 2019. Analytical outcomes of thirty-six surface water samples collected in Pre-monsoon and Post-monsoon seasons are well within the permissible limits as per BIS, 2012 and WHO 2011 for drinking and domestic purposes. Water quality characterization for the assigned use shows that maximum surface water samples fall under excellent to good water quality index and are suitable for drinking without conventional treatment. The Piper trilinear diagram classified 100% of surface water samples for both seasons’ falls in the fields of Ca 2+ -Mg 2+ -HCO 3 − water type indicating temporary hardness. Abundance of ions in the water samples is in the order: anions HCO 3 − >Cl − >SO 4 2− >NO 3 − and cations Mg 2+ >Ca 2+ >Na + >K + . PCA identifies that the surface water chemistry is influenced by natural factors as well as minor anthropogenic activities in both the seasons. The correlation matrix has been prepared to analyse and observe the significance of the factors on the assessment of river water quality. Periodic assessment of surface water samples of the Parbati river and adjoining areas should be carried out. This approach will help in finding out any contamination of water occurring due to rapid socio-economic development as well as explosion of tourism industry in the region. Present study will work as baseline database for any future work in the region.