<p>Groundwater vulnerability assessment is crucial for protecting water resources, especially in regions like the Niger Delta, where alluvial aquifers are highly susceptible to contamination due to anthropogenic and natural influences. This study is carried out with the aim of identifying and assessing areas at potential risk and threats that could influence groundwater vulnerability by using the DRASTIC model, vertical and horizontal intrinsic vulnerability approach. Twenty vertical electrical soundings (VES) were employed which delineated four subsurface geoelectric layers. The factors were evaluated, and their scores were combined; the results revealed variations in each factor. The DRASTIC vulnerability index (DVI) delineated the study area into three vulnerability classes, 5% low, 60% moderate, and 35% high. The vertical intrinsic vulnerability which considers vulnerability from sources above the water table identified weak (5%), average (20%), high (55%), and very high (20%) vulnerability classes. The horizontal intrinsic vulnerability which considers the lateral propagation of contaminants classified the area into average and strong vulnerability. The combination of vertical and horizontal intrinsic vulnerability gives the global vulnerability which delineated the study area into average (15%) and very strong (85%) vulnerability. The statistical analysis of the DRASTIC model identified net recharge as the parameter with the most significant influence on groundwater vulnerability followed by the impact of the vadose zone while hydraulic conductivity was the least. This study provides a systematic and comprehensive approach to appraising groundwater vulnerability and also gives information that will guide in effective monitoring and management of groundwater resources.</p> Graphical Abstract <p></p>