LAUSR

Abstract Groundwater vulnerability and risk assessment is an essential step for preventing and controlling contamination in any area. DRASTIC model with modification incorporating land use (LU) widely used for assessing groundwater vulnerability worldwide. The present study used this modified model termed as DRASTIC-LU considering LU as a significant parameter in addition to other conventional DRASTIC parameters. Geographic information system employed to prepare and integrate different parameter maps led to demarcate the risk zones in a catchment of Damodar River, Jharkhand, India. Final DRASTIC-LU map was categorized as low (19.50%), moderate (34.02%), high (29.90%) and very high (16.58%) risk zones of groundwater contamination. Validation of models done through Spearman’s rank correlation coefficient (ρ) and receiver operating characteristic curve using nitrate concentration in groundwater, which indicated DRASTIC-LU (ρ = 0.893; AUC = 71.65%) had a better agreement than DRASTIC model (ρ = 0.7818; AUC = 67.36%). Thus, such modification in DRASTIC improves the performance of the model.