GIS BASED VULNERABILITY MAPPING OF GROUND WATER USING DRASTIC MODEL IN DELHI REGION, INDIA

Abstract

Freshwater resources amounts to only 31 % out of total water resources in which 1 % surface water has been exploited extensively. The ministerial and other report has been evidenced its exploitation. There is a continuous deterioration in the ground water quality along with the depletion of the levels of Ground Water. The epicentre of major interventions and setting severe pollution standards, have been picked up for this study in Delhi. Setting up a priority list are the precursor of Vulnerability mapping of any area which gives an information about its necessity to taken care of and taking actions before its gets into a irreversible and implacable scenario. An average ground water level of Delhi is varying from 2-65 mbgl. In the study for vulnerability mapping of Delhi, the DRASTIC Model of ARCGIS is used. DRASTIC model is a combination of Groundwater table depth, recharge rate, aquifer media, soil profile, topography, effects on the vadose zone, and hydraulic conductivity are some of the factors to consider. After running the model was mapped appropriately via considering the statistics available for the period 2019–20. The contour mapping shows that Delhi's south, west, and north eastern regions are the most vulnerable, possibly as a result of unlined drainage, rapid growth, and the presence of local dumpsites. Studying the flow of pollutants that leak into groundwater from waste sites enables the identification of major pollutant concentration locations. The idea of "digital transformations" could be used in the policies formulation of this issue. The report also discusses capacity building, policy interventions, and technological initiatives that could be used.