This is PhD work done in the context of the IUC-JU project. Contacts: PhD: supervisor: Remediation of environmental pollution in Jimma town, Ethiopia, caused by wastewater discharge through development of low cost onsite treatment systems Alemayehu Haddis Promoters: Bart Van der Bruggen, Ilse Smets: KU leuven, Belgium Introduction Waste water treatment in developing countries should be simple, affordable and effective. Current conventional technologies for wastewater treatment, such as activated sludge and tertiary nutrient removal are too costly to provide a satisfactory solution for the increasing wastewater problems in developing regions. This research is designed to analyze and quantify the extent of pollution loading on the Awetu – Boye- Gilgel Gibe river basin and develop small scale cost effective and efficient method of waste water treatment system in Ethiopia that foster sustainable use of water resources. Constructed wetlands seem to be a promising solution to point sources of pollution and this project will assess remediation possibilities by experimenting SSFCWs and SSF as potential technologies. Objectives 1.Make baseline survey and map point sources of pollution along the Awetu-Kito drainage basin in Jimma Town 2.Quantify and characterize Jimma University wastewater 3.Evaluate existing wastewater treatment systems in Jimma and Ethiopia 4.Develop and test the efficiency of Subsurface Flow Constructed Wetlands (SFCWs) and Slow Sand Filters (SSFs) 5.Modeling and optimization for the removal of BOD, NH 4, NO 3, TSS, Total Phosphorus and pathogens in constructed wetlands 6.Improve the wastewater management system of Jimma University in view of remediation of receiving streams in Jimma town Methodology Surveying and mapping point sources of pollution on Awetu and Kito rivers in Jimma Town, SW Ethiopia to be conducted A HSF CW and SSF to be developed at JU campus for treatment efficiency and system description Bench scale models at Jimma University Environmental Health laboratory to be established Modeling for optimized nutrient removal at KU Leuven Policy and Practice linking Methodology 1. Description of existing situation - Literature review - Field visit - Sampling and analysis 2. Selection of low cost onsite wastewater treatment system - Evaluation - Design criteria 3. Bench scale Expt. - Rate constant - Soil porosity - Treatment efficiency 4. Pilot plant - Si te preparation and construction - Planting macrophytes - Running the pilot plant Sampling and Analysis Work Packages Cell configuration Results (Extracted from the preliminary f findings of work packages 1 & 2 only) - None of the surveyed wastewater treatment systems are functioning - Jimma University is a major contributor to the pollution of the surrounding environment and Awetu river - Constructed wetlands and Slow sand filters are promising technological options for developing countries Onsite low cost waste water treatment systems are technologically feasible and economically affordable for developing countries like Ethiopia. Existing treatment technologies are not efficient and cant be sustained. Subsurface flow constructed wetlands and sand filters must be fully described for use in Ethiopia a) Sampling stations b) Concentration of DO and BOD C) Concentration of Ammonia, Nitrites & Nitrates Conclusion