International Journal of Scientific & Engineering Research, Volume 6, Issue 4, April-2015 1026 ISSN 2229-5518 IJSER © 2015 http://www.ijser.org Characterization of Abattoir Wastewater and Evaluation of the Effectiveness of the Wastewater Treatment Systems in Luna and Kera Abattoirs in Central Ethiopia Abrha Mulu , Tenalem Ayenew Abstract— The objectives of this study were characterization of abattoirs wastewater and evaluation of the performance of their wastewater treatment system (WWTS). Samples from untreated effluents of Kera and Luna abattoirs, and treated effluent of Luna abattoir were examined using standard procedure over the duration of two months period of dry season. It was found that extremely high turbidity, color, TS, TSS, BOD5, COD, NH3-N, NO2--N, NO3--N, S-2, SO4-2, PO4-3, TP, FC, TC and FOG. As a result except temperature and pH, the levels of all these parameters of the raw wastewater did not comply with effluent discharge limit of the country. The values of most parameters measured were significantly higher for Kera abattoir than Luna abattoir, at 0.05 significant level of post Hoc ANOVA. The Luna abattoir lagoon, overall percentage removal of the above parameters were 56.67%, 63.22%, 63.77%, 88.68%, 91.59%, 90.91%, - 743.08%, 84.33%, 97.7%, 40.76%, 89.19%, -117.43%, -11.43%, 50.41% , 36.30%, and 66.18% respectively which were also not complying with the Ethiopian EPA discharge limit. There is a need of establishment and improvement of abattoir wastewater treatment system, as well as an intervention of regulatory bodies to ensure discharging of high quality treated final effluents by the abattoir industries. Index Terms— Abattoir wastewater, Bacteriological, Evaluation of WWTS, Lagoon, Physicochemical characteristics ——————————  —————————— 1 INTRODUCTION thiopia has the largest livestock population in Africa, with an estimated 47.57 million cattle, 26.12 million sheep, and 21.71 million goats [1]. Ethiopia’s increasing human popu- lation, coupled with expanding urbanization and higher aver- age income is putting increasing pressure on the meat supply. The increasing demands on meat in the country led to expan- sion of abattoir industries in number and capacity. Among those are Kera abattoir and Luna abattoir in Addis Ababa and Modjo respectively. Despite the importance of those indus- tries, they consume large amount of water resource for wash- ing of carcasses after hide removal from the animals; carcass washing after evisceration; equipment and facilities washing. These activities result to generate large amount of wastewater along with other by-products including blood, inedible inter- nal organs and intestines, bone, urine and feces, soft tissue removed during trimming and cutting, soil from hides and hooves, solubilized fat, and cleaning compounds. Untreated abattoir wastewater comprises a mixture of fats, proteins and fibers, resulting in a high content of organic mat- ter and causes a contaminating effect to the rivers and sew- age systems. It also increases nitrogen, phosphorus, solids and BOD5 levels of the receiving water body, potentially leading to eutrophication [2, 3, 4, 5]. However, in the Addis Ababa city and its surrounding areas the effluents from abattoirs are di- rectly or indirectly discharged into nearby rivers with and /or E ———————————————— Authors • Abrha Mulu (MSc) is a lecturer of Environmental Chemistry and Toxicology in Aksum University, Ethiopia , P.O.B: 1010 and currently pursuing PhD degree program in Environmetal Science in Addis Ababa University, Ethiopia, PH:-+251-913499472, P.O.B: 1176 , E-mail: chem.mulu@gmail.com or chem.mulu@yahoo.com. • Tenalem Ayenew (PhD) is a professor of Hydrogeology, Depart- ment of Earth Science, College of Natural Science, Addis Ababa University, AddisAbaba, Ethiopia., E-mail:tenalema@yahoo.com. IJSER