Washington, D.C.-Millions of acres of farmland in developing countries – primarily in Asia, but also in sub-Saharan Africa and in many Latin American cities – use untreated or partially treated wastewater for irrigation and fertilization, according to a survey by the International Water Management Institute (IWMI) published by the online National Geographic. “Irrigating with wastewater isn’t a rare practice limited to a few of the poorest countries,” said Liqa Raschid-Sally, IWMI researcher and lead author of a report on survey results. “It’s a widespread phenomenon, occurring on 20 million hectares across the developing world, especially in Asian countries.” The report points out that wastewater use is critical to farmers’ incomes and urban food security, but raises health concerns. In over 70 percent of the 53 cities studied, more than half of urban agricultural land is irrigated with wastewater that is either raw or diluted in streams. The report stated that the most common use is for vegetables and cereals, which raises concerns about health risks, particularly vegetables that are consumed uncooked. On the other hand, wastewater agriculture was found to contribute importantly to urban food supplies and to help provide a livelihood for the urban poor, especially women and recent migrants from the countryside. The survey concluded that the widespread practice is virtually inevitable where developing countries lack suitable transportation to deliver large quantities of perishable produce to urban areas, and because of widespread water shortages and lack of access to clean water in most areas.
Transparency Across the Fertilizer Value-Chain