GIS-Based Evaluation of Water Quality Index of Groundwater Resources in West Bokaro coalfield, India

Abstract

Water Quality Index (WQI), a technique of rating water quality, is an effective tool to assess quality and ensure sustainable safe use of water for drinking. The present work is aimed to assess the groundwater quality of West Bokaro coalfield region for knowing the suitability of drinking purpose by calculating the WQI and using Geographical Information System (GIS) techniques. Thirty three groundwater samples were collected from dug wells during post-monsoon, 2012 for comprehensive physico-chemical analysis. Ten parameters were considered for calculating the WQI such as: pH, fluoride (F ), chloride (Cl ), nitrate (NO 3 ), sulphate(SO 4 2), bicarbonate (HCO 3 ) calcium(Ca 2+ ), magnesium (Mg 2+ ), total hardness (TH) and total dissolved solid (TDS). The spatial distribution maps of the above mentioned parameters were prepared by using GIS, software. The computed WQI value ranges from 21 to 131 with an overall average of WQI value 73. More than half of the locations fall in Excellent to Good category indicating the groundwater in the study area is suitable for drinking purposes.