Identification of groundwater potential zones considering water quality aspect

Abstract

To evolve a proper management scenario for groundwater utilization, identification of groundwater potential zones is an important step. In the present study, an attempt has been made to identify possible groundwater potential zones both in terms of quantity and quality. A methodology is proposed for identification of groundwater potential index (GWPI) and a new water quality index (WQI) based on analytic hierarchy process. The proposed methodology has been applied to the shallow alluvial aquifer of central Ganga basin, Kanpur (India). Land use/land cover, soil, geology, recharge rate, drainage density, rainfall, slope, elevation, normalized difference vegetation index, groundwater depth or depth to groundwater table are used for GWPI calculation. Moreover, WQI considers alkalinity (as CaCO3), magnesium (Mg2+), total dissolved solids and fluoride (F−) as influencing attributes. Final integration of attributes yield GWPI and WQI map. The resulting GWPI map has been classified into three groundwater potential zones namely: good, moderate and poor covering 26.94, 43.76, and 29.30 %, area, respectively. The WQI map has been classified into five quality zones namely: above permissible limit, poor, moderate, good, very good covering 12.39, 7.63, 15.17, 38.18, and 26.64 % area, respectively. Monitoring data from well locations along with GWPI and WQI map reveals the proper potential zones. This analysis demonstrates the potential applicability of the methodology for a general aquifer system.