In urban areas, most of the residential, institutional, commercial and industrial centers provide a waste management sanitary facilities such as septic tanks and traditional pit latrines to collect and dispose the generated wastewater. However, recently the effect of these wastewater management sanitary structures on groundwater quality has become a great concern in most developing countries such as Ethiopia and now it is the most challenging issue in Bahir Dar city. To examine the effect of wastewater on groundwater quality spatially and temporally, 12 groundwater sampling stations were selected purposively throughout the city and a total of 216 samples within 6 months of January 2019 up to August 2019 were collected. The collected groundwater samples were analyzed both in situ and in the laboratory to determine temperature, pH, turbidity, electric conductivity (EC) and total dissolved solid (TDS), chloride, nitrate, phosphate, total hardness, bi-carbonate and lead and Escherichia coli (E. coli). Differences in groundwater quality parameters between the sampled stations were compared to identify the pollutant sources and level of compliances with certain water quality criteria. Based on cluster analysis, the sampling stations were classified into threemajorcategories; clusterone(including W2 and W3)ismoderatelypollutedregion, cluster two (including W8, W11, and W12) is the most polluted region whereas cluster three(including W1, W4, W5, W6, W7, W9, and W10)istheleastpollutedregionsamong the sampled regions. The overall results obtained from this study showed that E.coli and phosphate concentration levels were beyond the WHO standard in all sampled stations; whereas, turbidity, EC and TDS concentration in Shum_Abo, and Belay_Zeleke sub-city were also not according to the drinking water quality standard. In general, the results from this research would help in developing the best management practices for the Bahir Dar municipal water scheme and for the regional water scheme program in the future and provide information for formulating appropriate framework for an integrated groundwater management strategy.