The document analyzes the hydrochemical facies and water quality of coastal aquifers in eastern Niger Delta, Nigeria. Hydrogeological investigations found the aquifers are largely unconfined sands with some semi-confined areas. Water quality analysis of 140 groundwater samples found wide ranges and high standard deviations, indicating substantial quality differences within the study area. Six hydrochemical facies were identified using geochemical plots: Na-Cl, Ca-Mg-HCO3, Na-Ca-SO4, Ca-Mg-Cl, Na-Fe-Cl, and Na-Fe-Cl-NO3. Saltwater intrusion between 5-185m and high iron between 20-175m were found natural