National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm. Valcea, Uzinei Street no. 4, P.O. Box Râureni 7, 240050, Râmnicu Vâlcea, Romania

ABSTRACT

The present work aims at assessing the water quality index (WQI) in the surface water of Olt River by monitoring three sampling locations for a period of 12 months from December 2014 to November 2015.The surface water samples were subjected to comprehensive physico-chemical analysis involving major cations (Ca²⁺, Mg²⁺), anions ( Cl^-, SO₄^2-, NO₃^-, PO₄^3-) and general parameters (pH, electrical conductivity, total dissolve solids, total hardness, turbidity). Results demonstrated that WQI values ​​for the sectors of water analyzed, water is classified as excellent values ​​between 12.97 to 21.23  in spring, winter, autumn seasons and  good water class in summer season with WQI value of 29.42. The seasonal values of WQI indicates that surface water is affected more during the summer season than in spring, autumn and winter. This method appears to be more systematic and provide comparative evaluation of the water quality in different seasons of the year. Therefore, it may be helpful as marker for the public to better understand the quality of water as well as tool for the water quality management.

Keywords: Water quality index, Physico-chemical, River water.