In an important first for this region, the Food and Agriculture Organization of the United Nations (FAO) has published a new book compiling a wealth of information on wastewater re-use for agriculture. Available in Spanish, the book was prepared in collaboration with the International Water Management Institute (IWMI) and CGIAR Research Program on Water, Land and Ecosystems (WLE), which IWMI leads. The book’s editor is Javier Mateo-Sagasta, formerly with FAO and currently leader of IWMI’s Water and Health Research Group.
While rich in water resources, the Latin America and the Caribbean region is experiencing more frequent droughts and local water scarcity, as rapid urban growth drives up water demand and intensifies competion between agricultural and other uses. Growing cities also generate huge volumes of wastewater, but treatment capacity has fallen behind. Currently, it is sufficient to handle only about 40% of the 30 cubic kilometers of municipal wastewater that the region generates every year, and the proportion actually treated is even lower because of inadequate maintenace. Only a marginal amount of treated water is then directly reused for agriculture in a planned, productive and safe manner. Wastewater thus remains a largely untapped resource.
Most wastewater is discharged without treatment into the environment, and is either not put to productive use or is diluted in the region’s waterways and reused unsafely downstream. Fecal pollution has resulted in heavy degradation of 25% of rivers in the region. This water is reused downstream to irrigate millions of hectares of cropland, often unintentionally, posing serious risks to the health of farmers and consumers as well as to the environment.
The new book brings this issue into sharp focus, calling for concerted action to mitigate the health and environmental risks in the region’s peri-urban hotspots and to capitalize on the opportunities that reuse brings. The Sustainable Development Goals (SDGs) – specifically the SDG 6 target for water quality, wastewater treatment and safe reuse – have aroused great interest in addressing these challenges and opportunities, and countries across the region are working to strengthen their capacity for safer and more productive use of wastewater.
This book will help guide such efforts by making valuable information available to a wide audience, including regional and global organizations, governments, civil society, students and the media. In addition to documenting the current status of wastewater reuse, the book outlines the technical, economic and institutional challenges involved in dealing with the issue as well as the capacities that need to be developed; explains key principles to aid the design and implementation of projects and policies; and identifies cases of success.