Constructed Wetland as an Efficient Technology for the Treatment of Urban/Industrial Wastewater in the Arid Regions: Morocco as a Model

Abstract

AbstractHuman activities have caused holistic changes in earth climatic conditions, translated by decreased rainfall in many regions. Sadly, these changes are more expressed in poor and developing countries, especially in the African continent. Many regions suffer from long periods of drought and form water quality degradation, leading to waterborne diseases that spread dangerous diseases such as cholera and typhoid fever. To overcome these issues, many countries have adopted water management strategies based mainly on wastewater treatment and its reuse in agriculture to lower the pressure applied to freshwater resources. However, this could be a relevant issue in developing countries when using intensive systems such as activated sludge, membrane bioreactor, and sequencing batch reactors, due to their high costs in all steps of the wastewater treatment plant, from the construction (e.g., huge facilities, intensive technologies) to the exploitation (e.g., energy consumption, maintenance, qualified staff). On the other hand, extensive systems or low-cost technologies (e.g., infiltration-percolation, constructed wetland (CW), and algal pond) are more adapted to the developing countries’ context due to their low cost in construction, easy operation and zero energy and chemicals’ consumption. Among these systems, CW was distinguished from other systems not only by being a low cost and easy to implement technology but also by exhibiting great results in terms of wastewater treatment from both domestic and industrial activities (e.g., olive mill wastewater, tannery), achieving in some cases a high quality of water reusable in agriculture. Therefore, the CW technology has experienced a remarkable spread in developing countries, especially those under arid climates such as Morocco, one of the African leaders in water management. The aim of this chapter is to make a comparative analysis of wastewater treatment systems used in Morocco as an arid area and highlight the effectiveness of CW regarding its adaptation to the limited resources in this arid context and their treatment capacity for the different types of wastewater, including the tentative strategies for optimizing urban and industrial effluent treatment.KeywordsConstructed wetlandUrban wastewaterIndustrial wastewaterDecentralized wastewater treatment plantMorocco