Sustainable Tertiary Wastewater Treatment Is Required for Water Resources Pollution Control in Africa

Abstract

T here is a significant lack of proper wastewater treatment in most African countries, especially in sub-Saharan Africa.Untreated sewage effluent is one of the most common types of pollution found around urban rivers and in groundwater sources in many African cities.By 2020, 75-250 million people in Africa may be exposed to increased water stress due to climate change and pollution will only exacerbate the situation. 1 In Kenya, for example, most municipal wastewater treatment plants (WWTPs) discharge partially treated or untreated wastewater containing high levels of organic matter with mean effluent TSS, COD cr , and BOD 5 being 246 mg/L, 253 mg/L and 98 mg/L, respectively, (as of 2004) against a discharge requirement of 30, 50, and 30 mg/L, respectively.This situation replicates itself across most cities in the developing world.Dar es Salaam, Accra, Khartoum, Harare, Maputo, and Kampala, to name but a few, discharge treated and untreated sewage into their water bodies.In 2004, only about 14% of sewage was collected and treated in Dakar, and the rest was discharged into the sea without treatment. 2The story is the same in Latin America, where less than 15% of the wastewaters collected in sewered cities and towns is treated prior to discharge. 3he inadequacy in treatment stems from a number of reasons that include poor operation and maintenance of existing systems or complete breakdown of the same, overloading, and lack of tertiary systems for extended