Water and Wastewater Treatment in Africa – Current Practices and Challenges

Abstract

Water and Wastewater Treatment in AfricaCurrent Practices and ChallengesSustainable access to safe drinking water and basic sanitation is an important part of the millennium development goals (MDGs). For most African countries, an extensive effort is needed for the last three remaining years for the achievement of the MDGs, especially in Sub-Saharan Africa. Current practices for water and wastewater treatment in Africa are insufficient to ensure safe water and basic sanitation. To address this challenge, joint efforts are needed, including transforming to green economy, innovating technologies, improving operation and maintenance, harvesting energy, improving governance and management, promoting public participation, and establishing water quality standards. IntroductionAfrica is often characterized by its clean water and abundant biodiversity [1]. It is no doubt that water quantity and quality is of vital importance for the ecosystem [2,3]. Unfortunately, as the world's second-driest continent after Australia, Africa has only 9% of global renewable water resources to support 15% of the global population [1]. The lack of water in Africa is further aggravated by insufficient treatment of water and wastewater, particularly with rapid population growth and urbanization [2].At present, however, the efforts to improve drinking water quality and wastewater treatment are not keeping pace with population growth and urbanization [4,5]. The growing population and rising economy has resulted in increasing consumption of water and discharge of wastewater, which cause heavy pollution [6]. Water pollution not only reduces available freshwater, but also affects human health and ecosystem [3,7,8]. According to the millennium development goals (MDGs), the proportion of people without sustainable access to safe drinking water and basic sanitation should be reduced in half by 2015 [9,10]. In fact, water and wastewater treatment is significant for the realization of the MDGs [11,12]. For example, goal 1 (to eradicate extreme poverty and hunger) is related to water treatment because the access to safe drinking water can save the time and cost to collect daily water, thus people may have more time to work and to get food [1]. Goal 2 is to achieve universal primary education. Some kids cannot go to school due to the fact that they have to collect drinking water, or they have to quit schools due to water-borne diseases [1]. Goal 3 (to promote gender equality and empowering women) is related to water treatment because the burden of water collection in Africa falls disproportionately on girls and women [1]. Goal 4 (to reduce child mortality rates) is related to water treatment because improving water quality can reduce child mortality [1]. Goal 5 (to improve maternal health) is closely related to water treatment [13]. Goal 6 is to combat HIV/AIDS, malaria, and other diseases. It was shown that some diseases including malaria are related with water treatment [14,15]. Goal 7 is to ensure environmental sustainability. One essential part (t...

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Testing Metallic Iron Filtration Systems for Decentralized Water Treatment at Pilot Scale

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“…Conventional water treatment often calls for complex multistage processes (namely coagulation, disinfection, flocculation, sand filtration, screen-filtration, ozonization, sedimentation) and requires a wide array of chemicals (namely chlorine, flocculents, hydrogen peroxide, lime, ozone). The processes therefore also typically require specialist expertise for installation and maintenance [4,[10][11][12][13]. As a result conventional wastewater treatment facilities are often expensive to install and maintain and have a high carbon footprint.…”