Background and Objective: Abattoir effluent, high in organic and inorganic matter, is known to have direct and indirect effects on water sources surrounding it. Thus, the quality of well water samples surrounding upstream and downstream of Onyearugbulem abattoir were investigated. Materials and Methods: The pre-surveillance study was carried out using the questionnaire method. Physico-chemical properties and bacteriological counts of well water samples were done using standard methods. Results: The pH downstream were slightly acidic with values ranging from 6.7-6.9 compared to 6.9-7.3 obtained from wells upstream. The temperature of water upstream and downstream ranged from 26-30EC. Both the temperature and pH upstream and downstream corroborates with WHO standard (30-32 and 6.5-8.5EC) for drinking water. The total bacteriological counts were higher downstream with about 2.0×10 4 CFU mLG 1 as against the WHO limit of 1.0×10 2 CFU mLG 1 . Conclusion: High concentration for most parameters especially the bacteria count is an indication of point pollution use through the affluent and non-point pollution from other domestic activities like washing of clothes and defecation in the area. This study provided an explicit revelation of pathogenic microorganisms in some of the wells located downstream of Onyearugbulem abattoir, resulting from the improper treatment of slaughterhouse wastewater discharge which pose a public health problem and environmental hazard to the residents of this community.