International Journal of Science, Engineering and Technology Research (IJSETR), Volume 3, Issue 12, December 2014 3455 ISSN: 2278 – 7798 All Rights Reserved © 2014 IJSETR Abstract— Influent and effluent wastewater samples were collected during January 2011 to December 2013 from Old Rustamiya Project, Baghdad. The present study focuses on the levels of biological pollution in order to assess the effluent (treated) wastewater produced from Rustamiya WWTP for stage0 and stage1 and to evaluate its suitability for discharged into river. Parameters measured were pH, Total Suspended Solid (TSS) and biological parameters COD and BOD5. The results concluded that the removal of BOD is highest throughout the year as the efficiency of WWTPs range between 91.21 and 92.95 in the whole period of study. The results also showed that about 88.71% and 87.47% COD removal can be achieved in stage0 and stage1, respectively, and the values of TSS and pH for the final effluent produced from Al-Rustamiya WWTP meet the values determined by the Iraqi National Standards set by Regulation 25 of 1967. Index Terms— BOD, COD, Efficiency, Rustamiya, WWTP. I. INTRODUCTION The problem of getting rid of wastewater is one of the main problems facing the world in the time being. That is due to bad effects of wastewater on human and environment when discharged into rivers [1]. The amount of collected and treated wastewater is likely to increase considerably with population growth, rapid urbanization, and improvement of sanitation service coverage [2]-[5]. Wastewater originates from domestic, commercial, and industrial sources. In many networks the domestic component is the largest. The defining variable is domestic water consumption, which is linked to human behavior and habits. Very little water that is used by households is actually consumed, but rather is degraded in quality and then discharged as wastewater [6]-[8]. Eman Shakir Awad, Environmental Research Center, University of Technology, Baghdad, Iraq, Abdul Hameed M.J. Al Obaidy, Environmental Research Center, University of Technology, Baghdad, Iraq, Hanaa R. Al Mendilawi, Old Rustamiya Project, Mayoralty of Baghdad, Baghdad, Iraq. The sewerage network that was established between 1960 and 1980 worked on the basis of the separate system, but a combined system has been adopted since 1980. In general, the quantity of wastewater generated within the urban and rural areas of the mayoralty of Baghdad are estimated at 1,426,013 and 2,354 cubic meters per day respectively. However, the capacity of all wastewater treatment plants in the mayoralty of Baghdad was estimated at 789, 200 cubic meters per day, in which it represents as 55% of the total capacity of wastewater. The secondary treated wastewater effluent for Iraqi (WWTP) was designed to produce an average of final effluent quality of biological oxygen demand (BOD) and total suspended solids (TSS) as 20 and 30 mg/L, respectively to meet the Iraqi National Standards set by the Regulation 25 of 1967. It reported that each day 500,000 cubic meters of raw sewage are discharged into Iraqi waterways [9]. Therefore, the objective of this research was focuses on the levels of biological pollution in order to assess the effluent (treated) wastewater produced from Rustamiya WWTP for stage0 and stage1 and to evaluate its suitability for throwing into river. II. MATERIAL AND METHODS A. Study Area The Iraqi capital, Baghdad, has the highest level of sanitation provision with about 80% of the population connected to sewer conveying sewage to treatment facilities. Al-Rustamiya Project is the oldest sewerage network in Iraq which provision of services to a third of the population of Baghdad and distracts sewage into the Diyala River after treatment. The project is located on the banks of Diyala River south of the Baghdad city at Rustamiya area. The project serves areas of Baghdad which sited between Al-Jaish channel at the east and the Tigris River at the west, starting from the Adhamiya district in the north down to the Rustamiya area in the south, show in Fig. 1. Environmental Assessment of Wastewater Treatment Plants (WWIPs) for Old Rustamiya Project Eman S. Awad, Abdul Hameed M.J. Al Obaidy, Hanaa R. Al Mendilawi