Mapping groundwater nitrate contaminant risk using the modified DRASTIC model: a case study in Ethiopia

Abstract Background Nitrate contamination of groundwater often occurs in urban and industrial areas due to point non-point sources anthropological activities. Groundwater constitutes a significant portion the water supply system for Bahir Dar City Ethiopia, though level pollution is not known. This study was conducted assess extent aquifer (nitrate) based on contaminant vulnerability risk mapping using GIS integrated modified DRASTIC model. A field survey collect samples from boreholes nitrate analysis modify Results Compared original intrinsic assessment, land use as external factors changed moderate-high high class 18 88%. The FR-APH model showed good correlation (0.53) compared other methods. Based model, about 31% area under moderate range, 39% range while 30% low range. Conclusions map central part flat slope shallow depth groundwater. Besides, sensitivity indicated that contribution media vadose zone found trivial. In general, at Darwas vulnerable needs proper management.