Water and wastewater treatment in developed and developing countries: Present experience and future plans

Water, an invaluable resource, operates within the confines of a closed system on Earth, precluding the transfer or exchange of matter. This intrinsic limitation underscores the critical need for judicious water management. As a result of industrialization and urbanization, there is an increasing health risk from the consumption of polluted water, with a severe impact on the socioeconomic development of a nation's human and environmental resources. Access to good quality water and sanitation is one of the SDG goals. It has, therefore, become essential to protect waterbodies from continuous pollution by developing effective and efficient water and wastewater treatment methods to deliver portable and safe drinking water fit for human and animal consumption in line with the SDG goals. The various conventional water and wastewater treatment methods, such as activated carbon, coagulation, sedimentation, and biodegradation, have been judged relatively uneconomical. Ongoing research endeavors in both developed and developing nations are driven by the imperative to effectively treat drinking water, groundwater, and industrial wastewater, mitigating the pervasive issue of water pollution. This chapter underscores how population growth impacts the accessibility of high-quality water resources in both developed and developing contexts. It discusses conventional water and wastewater treatment methodologies and their associated challenges. Furthermore, this exploration delves into the forefront of research trends, delving into the application of nanotechnology, nanomaterials, and advanced membrane techniques spanning microfiltration, ultrafiltration, and nanofiltration, all aimed at revolutionizing water and wastewater treatment processes.