Study on groundwater pollution and its human impact analysis using geospatial techniques in semi-urban of south India

Groundwater recharging and thus renewable groundwater supplies will experience considerable changes due to climate change. The present investigation focussed to evaluate the susceptibility of subsurface water in rapid developing textile industrial region of Southern India. To determine the aquifer's susceptibility, the DRASTIC-LU Remote sensing and GIS based vulnerability model was applied and the results were compared with human activity risk (HAR) analysis to ensure the water borne disease on human health. DRASTIC layers like Depth to Water, Recharge, Aquifer Media, Soil Media, Topography, Impact of Vadose Zone, and Conductivity of the Aquifer are overlay along with respective LULC layers (2010 & 2020) to generate the DRASTIC-LU models for 2010 and 2020. The results of the DRASTIC LU groundwater vulnerability pattern between the range of 25-201 and 55 to 212 in 2010 and 2020, and have been classified into five categories from very high to low susceptibility. The effects of various Drastic-LU parameters were 69%, 76%, 81%, 82%, 63%, 79%, and 84%, respectively, based on the output of the sensitivity analysis method. The areas of Northern, Central, Central East and Central Western portions were identified as maximum and very highly vulnerable on the DRASTIC-LU index map and rest of the locations were classed as low and medium in terms of vulnerability. The outcomes of a risk analysis of human activity revealed that areas with high human activity density, such as of Northern, Central, Central East and Central Western portions were shown to be a vulnerable between the years 2010 and 2020, according to the results of human activity risk analysis.