Groundwater contamination near municipal garbage dumpsites was studied in Owerri, a city in southern Nigeria.The purpose of the study was to map aquifer contamination from landfill dumpsites within the Owerri metropolis and its environment using hydrogeochemical data. Groundwater samples were collected and examined at eight locations near landfill dumpsites. The result of the analysis shows that groundwater from the aquifers of all sampled locations is slightly acidic with an average pH value of 6.25. Bicarbonate, calcium and chloride have average concentrations of 26.19 mg/l, 4.25 mg/l and 0.26 mg/l, respectively. The results also show conductivity and total dissolved solids having an average value of 89.13 mg/l and 53.67 mg/l, respectively. These values fall within the maximum permissible Nigerian standards for drinking water quality and the World Health Standard for Drinking Water Quality. All the parameters did not exceed the NSDWQ (2007) standards except magnesium, which had a mean concentration of 1.16mg/l as opposed to the 0.20mg/l proposed by the Nigerian Standard of Drinking Water Quality. Also, future examination of the water resources within Owerri Metropolis should be done at least every two to three years by the government and relevant agencies to protect the health of people living within this environment.