Performance Evaluation of RBF Wells with Special Reference to Water Quality Parameters in Hard Rock Region of Tungabhadra Catchment

Abstract

Tungabhadra River is the chief source for drinking water and agriculture developments in Davangere and adjoining districts of Karnataka. It is reported that the water of Tungabhadra is getting polluted by the direct / indirect effluent discharges due to which people living on the river bank are facing the problem of drinking water. River Bank Filtration (RBF) wells which will naturally treat the polluted surface and ground water have been drilled in perpendicular to the river at a distance of 30m, 50m and 80m to understand the extent of treatment of RBF wells to provide clean and safe drinking water. The present study deals with the problems of water quality in a selected village (Somlapura) located in a hard rock terrain of river Tungabhadra, Karnataka, India. As a part of the investigation, water samples were collected from River Bank Filtration wells and adjoining river and aquifers were analyzed using standard methods. Outcomes of water quality presents that the concentrations of turbidity and total coliform were lesser in the RBF well water samples when compared to Tungabhadra River water samples. The water from RBF wells contained fresh water, which is highly mineralized and free from bacterial contamination relative to the water from river. However, groundwater of the adjoining aquifers showed wide variations in various physio-chemical parameters. From the analysis, unsafe levels of total coliforms (included E.coli and F. Coli) were detected in Tungabhadra River i.e., It varied between 1680 and 3179 MPN/100 ml. It is observed that the average removal efficiency of coliform bacteria from RBF well 1 & 2 was 99.84% and 99.82% respectively.