Impact of urbanization and study of water quality index on Gidadakonenahalli Lake, Bangalore urban district, Karnataka, India

Abstract

The water pollution of Gidadakonenahalli Lake in Bangalore city, Karnataka, India was studied. In order to determine the water quality of the lake the present paper attempted to evaluate the physico-chemical, biological and bacteriological parameters and it was analyzed for a period of one year from January 2010 to December 2010. The surface water samples was subjected to comprehensive physico-chemical analysis involving parameters such as water temperature, pH, total dissolved solids (TDS), electrical conductivity (EC), dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), chloride, total alkalinity, total hardness, phosphate, nitrate and sulphate. Biological parameters included quantitative analysis of planktons using ‘Sedwickrafter counting cell’. Fecal coliforms were enumerated by membrane filtration technique. Correlations coefficients were calculated and they identified the type of correlation existing among the physico-chemical and biological parameters of the sample water. Water quality index (WQI) was calculated using weighted arithmetic index approach. A significant seasonal variation in the water quality of Gidadakonenahalli Lake was observed during the present study. Water quality index value was 849.01. The result shows that the quality of water in the lake is severely polluted.