Safe use of wastewater in agriculture: The golden example of Nexus Approach

Abstract

Water, soil, and waste are three key resources associated with agriculture and thus food production as they are closely related to each other. An integrated management of these three resources can bring more benefits to society through increased resource usage efficiency. This approach is commonly known as the Nexus Approach. Safe use of wastewater in agriculture (SUWA) is a simple but powerful example of the Nexus Approach in action. It demonstrates how the sustainable management of one resource in a nexus can benefit the other resources in the same nexus. Wastewater irrigation not only addresses the water demand issues in water stressed areas, but also helps us "recycle" the nutrients in it. The process begins in the waste sector, but the implementation of such a management model can ultimately make a positive impact on the water sector as well as in soil and land management. On a global scale, over 20 million hectares of agricultural land are irrigated using wastewater. Developing countries and countries in transition need clear institutional arrangements and skilled human resources to address the technical, institutional, and policy challenges related to SUWA. From the UN perspective, SUWA also supports achieving some of the key Sustainable Development Goals (SDGs). Taking the wastewater irrigation in the Mezquital Valley in Mexico as an entry point, this chapter builds upon all above facts to provide an introduction to the book and also to illustrate SUWA as a Nexus Approach example.