Wastewater reuse in agriculture: A review

Abstract

Water scarcity is a growing global crisis worsened by the anticipated increase in the population to 10.2 billion by the year 2050, which is expected to boost the food demand by 60%. This rising demand for food will place additional pressure on already limited freshwater resources. Agriculture, particularly irrigation is the largest consumer for freshwater accounting for about 71.7% of global water withdrawal. The conventional water remains constant indicating that many of the countries will face severe water shortage by the year 2050. Wastewater represents an underutilized resource that can be treated and reused for agriculture. In India, where water stress is significant due to rapid urbanization and population growth, wastewater generation is expected to rise sharply. The types of wastewaters can vary according to their sources, necessitating the selection of appropriate treatment options tailored to each specific type of wastewater. The nation has advanced its sewage treatment capabilities, and estimates suggest that millions of hectares of agricultural land can be irrigated with treated wastewater. Utilizing treated wastewater reduces fertilizer consumption, boosts farmer’s income and improves agricultural yield. However, improper treatment of wastewater can lead to the accumulation of heavy metals, posing significant health risks to both humans and animals. Consequently, while the advantages of employing treated wastewater in agriculture are considerable, it is essential to adopt effective treatment methods to minimize any potential adverse effects on health and the environment. The adoption of wastewater irrigation is a viable strategy to address global water scarcity while promoting sustainable agricultural practices and reducing environmental impacts.