Assessment of Groundwater Quality Index, Suitability for Irrigation and Domestic Purposes in Krishna-Godavari Delta Region, Southern India

Abstract

The water quality index (WQI) is a significant indicator for evaluating the quality of drinking water for end-users. The present work is aimed to assess the groundwater quality of the Krishna Godavari delta region in Andhra Pradesh State, for knowing its suitability for domestic, irrigation, and drinking purposes by calculating the WQI parameters and comparing it with WHO and Indian Standards. A total of 105 groundwater samples each for both Pre-monsoon and Post-monsoon periods have been collected during June 2017 and January 2018. The following 11 parameters were taken into account when calculating the WQI: pH, Electrical Conductivity (EC), Total Hardness (TH), Calcium (Ca2+), Magnesium (mg2+), Bicarbonate, Chloride(Cl-), Nitrate (Na+), Sulphate, Potassium (K+), and Total Dissolved Solids (TDS). Based on the WQI result, the samples were divided into five categories: Excellent, Good, Poor, Very Poor, and unfit for drinking purposes. In Pre-monsoon and Post monsoon season, the water quality index is 9%, 25%, 30%, 22%, 15% respectively 16%, 41%, 31%, 7%, and 5%. It can be concluded that during pre-monsoon and post-monsoon season 67% and 43% of water is not suitable for drinking purposes respectively and hence they require treatment before usage.