Assessment of groundwater vulnerability using the GIS approach-based GOD method in Surat district of Gujarat state, India

Abstract

There are different sources of groundwater pollution among them industrial water disposal, seawater ingress, usage of pesti-cides and fertilizers in agricultural fields, and municipal and residential wastewater disposal. The aim of the study is to assess groundwater vulnerability in terms of quality using the GOD method using the Geographical Investigation System approach for Surat and its surroundings. Groundwater confinement, overlying strata and depth to water table are the three parameters that are used in the assessment of groundwater vulnerability. In this study, all three parameters are given by the conventional weights which are suggested by Foster 1987. Based on the study Mahuva, Mandvi, Umarpada and some parts of the Bardoli talukas lie in very high-vulnerability zones whereas another part of the study area lies in a high-vulnerability zone. Almost 35.98% of the area of the district lies in the higher-vulnerability zone. Depth to the water table and the overlying strata are very important parameters that effectively cause groundwater vulnerability. This study may help in groundwater quality man-agement, and watershed management as well as it is very much useful for the policymakers and local authorities as well as the government.