Department of Agricultural and Environmental Engineering, Federal University of Technology Akure, Ondo State, Nigeria

Abstract

The study examined the effect of Onyearugbulem abattoir wastewaters discharge on surface water quality in Akure. Water samples were taken at three different locations along the receiving water body namely the Upper Course (UC), Middle Course (MC) and the Lower Course (LC). UC samples were collected at the point of entry of the abattoir wastes; MC samples were taken about 50m from the point of entry while LC samples were taken about 100m away from the point of entry of the abattoir waste. The samples were collected, preserved and analyzed in the laboratory using standard methods. The wastewater parameters analyzed were dissolved oxygen (DO), pH, total suspended solid (TSS), total dissolved solid (TDS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), and heavy metals. The mean concentration of 0.24 mg/l for Cr and 0.02 mg/l for Pb exceeded the WHO (1993) and FEPA (1991) standard of 0.1 mg/l Cr and 0.01 mg/l Pb  for the discharge of wastewater into river, while the levels of nitrate, TSS and TDS were also higher than the WHO limits for the discharge of wastewater into river. The mean values of 1.9 mg/l, 1626.6 mg/l, 466.67 mg/l and 1666.67 mg/l for DO, COD, TSS and TDS exceeded the WHO permissible limit of ≥5mg/l for DO, N/D for COD, 500 mg/l for TSS and 500 mg/l for TDS for the discharge of wastewater from Onyearugbulem abattoir into the river. Based on the results obtained, the Abattoir Practice Regulatory body should be put in place by the Environmental Protection Agency to regularly regulate and monitor abattoir activities in the study area in order to prevent environmental pollution and health hazards caused by activities of abattoirs.